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Adaptec AHA-2740 Series User’s Manual

 Stock Number:  510381-00  /  Rev. C        (Page C-2)
Print Spec Number:  491709-00 Rev C
Current Date:  9/1/93           ECN Date:  9/14/93

Summary of Contents for 2740A - AHA Storage Controller Fast SCSI 10 MBps

Page 1: ...nnel AHA 2740T 2742T TwinChannel EISA to Fast SCSI Host Adapters User s Manual Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page A 1 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 ...

Page 2: ...tec and the Adaptec logo are registered trademarks of Adaptec Inc Printed in Singapore STOCK NO 510381 00 Rev C LL 9 93 Information subject to change without notice Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page A 2 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 ...

Page 3: ...nnel AHA 2740T 2742T TwinChannel EISA to Fast SCSI Host Adapters User s Manual Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 0 i Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 ...

Page 4: ... AT and Micro Channel are registered trademarks of International Busi ness Machines Corporation MS DOS is a registered trademark of Microsoft Corporation NetWare is a registered trademark of Novell Inc SCO is a registered trademark of the Santa Cruz Operation Inc UNIXisa registeredtrademarkandUSLisatrademarkof UnixSystemsLaboratories Changes The material in thismanual isforinformationonlyandissubj...

Page 5: ...circuit different from that to which the receiver is powered If necessary the user should consult the dealer or an experienced radio television technician for additional suggestions CAUTION Only equipment certified to comply with Class B computer input output devices terminals printers etc should be attached to this equipment and must have shielded interface cables Finally any change or modificati...

Page 6: ...Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 0 iv Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 ...

Page 7: ...gs 1 7 The On board Floppy Controller AHA 2742 2742T Only 1 8 Unpacking and Inspection 1 8 Adaptec Technical Support 1 9 2 Getting Started About This Chapter 2 1 Installation Overview 2 3 The Host Adapter and the SCSI Bus 2 4 Quick Installation 2 5 Prepare Your SCSI Devices 2 5 Install Your Host Adapter and Peripherals 2 6 Configure the Host Adapter 2 7 Installation 2 8 Termination on the SCSI Bus...

Page 8: ...Format Utility 3 20 Host Adapter Diagnostic Utility 3 21 4 Troubleshooting About This Chapter 4 1 SCSI Troubleshooting Checklist 4 3 Problems and Solutions 4 4 Conflicts With Other Options 4 7 APPENDICES A Specifications About This Appendix A 1 Technical Information A 3 Product Specifications A 3 Extended Industry Standard Architecture Interface A 4 SCSI Interface A 4 Electrical Interface A 4 Flop...

Page 9: ...rmance C 5 D Disk Drives Over 1 Gigabyte About This Appendix D 1 Extended Translation Using DOS 5 0 D 3 The DOS 1 Gigabyte Limit D 3 When to Use Extended Translation D 4 With DOS Version 5 Only D 4 Drives With Mixed Partitions D 4 Using Fdisk D 4 Questions and Answers About Extended Translation D 5 Glossary About This Glossary Glossary 1 Glossary Glossary 3 Index Index 1 Adaptec AHA 2740 Series Us...

Page 10: ...e 2 14 Connecting a Second Floppy Drive 2 22 Figure 3 1 Host Adapter Parameters 3 5 Figure 3 2 Selecting Interrupt Level 3 6 Figure 3 3 Selecting Bus Release Time 3 7 Figure 3 4 Selecting Data FIFO Threshold 3 7 Figure 3 5 Selecting Host Adapter BIOS Base Address 3 8 Figure 3 6 Selecting Host Adapter SCSI ID 3 9 Figure 3 7 Selecting SCSI Bus Parity 3 10 Figure 3 8 Selecting SCSI Selection Timeout ...

Page 11: ...d Physical Interface A 4 Table A 2 Output Signals A 4 Table A 3 Input Signals A 5 Table A 4 Internal Connector Pin Assignments A 6 Table A 5 External Connector Pin Assignments A 7 Table A 6 Output and Input Signals A 8 Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 0 ix Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 Table of Contents ix ...

Page 12: ...Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 0 x Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 ...

Page 13: ...rmation to assist you in troubleshooting problems that may occur during installation and configuration Appendix A Specifications lists technical specifications of the host adapter and its connectors which may be of use to the advanced user or technician Appendix B I O Operating Environment provides information on using your host adapter with various operating systems such as DOS Windows A brief di...

Page 14: ...ca Italics Used as a place holder for text you must determine and type in enter nn for number Also used for program and file names in body text the autoexec bat file Italics Used for emphasis is only supported and document reference refer to Chapter 2 Setting Up ALL CAPITALS Used for acronyms such as SCSI and CD ROM Hexadecimal Numbers Are followed by an h e g 330h Numbered Step Marker The symbol ...

Page 15: ...stions which may simplify the assembly and use of the host adapter Caution Failure to observe this type of advisory could result in damage to your system devices and or data WARNING This type of advisory is a visual alarm Failure to observe this type of advisory could result in injury to the user Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 0 xiii Print Spec Number 49170...

Page 16: ...Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 0 xiv Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 ...

Page 17: ...Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 0 x Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 ...

Page 18: ...Series The layout of the host adapter and all its major components The default settings of the host adapter and how to disable or enable the on board floppy controller How to get help from Adaptec Technical Support Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 1 1 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 1 1 ...

Page 19: ...Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 1 2 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 ...

Page 20: ...red to as the AHA 2740 Series The AHA 2740 Series of Host Adapters The AHA 2740 Series provides a high performance connection between the EISA Extended Industry Standard Architecture bus and the SCSI Small Computer System Interface bus The AHA 2740 Series is a bus master device that transfers data into host memory at burst rates of 33 MBytes sec These transfers are generally 32 bits wide except wh...

Page 21: ... Features Fast Data Transfer Rates Up to 33 MBytes sec on EISA bus 2 0 MBytes sec asynchronous SCSI data rate 5 0 MBytes sec synchronous SCSI data rate 10 0 MBytes sec synchronous Fast SCSI data rate Maximum Off loading the Host CPU On board sequencer SCSI PhaseEngine automates all SCSI protocol Low SCSI processing overhead Bus master DMA implementation Task scheduling and message based communicat...

Page 22: ...e superior SCSI 2 Alternative 1 external connector and standard internal ribbon connector Tagged queuing support Programmable active SCSI termination Multiple LUN support Parity handling in Data Message and Command phases Multiple Device and Applications Support The AHA 2740 2742 can be used to install up to seven SCSI devices The AHA 2740T 2742T can be used to install up to 14 SCSI devices The AH...

Page 23: ...Byte Managers and device module software available for all major operating systems Board Layout Figure 1 1 shows the location of the major components on the host adapter Table 1 1 provides a description of each component J2 J1 J4 J3 U2 U1 U5 U10 U9 J6 J5 PIN 1 PIN 1 PIN 1 Figure 1 1 Host Adapter Board Layout Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 1 6 Print Spec Num...

Page 24: ...ost adapter Refer to Chapter 3 Configuring the Host Adapter for information on changing any of the settings Table 1 2 Host Adapter Default Settings Description Default Setting Interrupt Level IRQ 11 Level Sensitive Bus Release Time 60 BCLKS Data FIFO Threshold 100 Host Adapter BIOS Base Address D8000h Host Adapter SCSI ID Device ID 7 SCSI Bus Parity Check Enabled SCSI Selection Timeout 256 millise...

Page 25: ...ponsible for any damage incurred during storage or shipment In case of damage return the host adapter to your distributor if the host adapter was delivered to you directly have the carrier note the damage on both the delivery receipt and the freight bill then notify the freight company representative so that the necessary insurance claims can be initiated Caution The host adapter is extremely sens...

Page 26: ...rs a day at 408 945 7727 1200 2400 9600 baud 8 data bits 1 stop bit no parity The Adaptec Technical Support Hot Line can be reached at 800 959 SCSI 7274 or 408 945 2550 M Th 6 00 a m to 5 00 p m F 6 00 a m to 3 00 p m PST The Adaptec Technical Support FAX can be reached 24 hours a day at 408 945 6776 Adaptec software can be ordered by calling 800 442 7274 M F 5 00 a m to 6 00 p m PST Additional do...

Page 27: ...Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 1 10 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 ...

Page 28: ...r and the SCSI bus The instructions an experienced user can use to quickly install the host adapter The instructions a user who is new to SCSI or has lim ited experience can use to install the host adapter and SCSI devices Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 2 1 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 2 1 ...

Page 29: ...Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 2 2 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 ...

Page 30: ...alling option boards in your computer refer to the more comprehensive instructions and illustrations found in the Installation section of this chapter For a brief discussion on how your host adapter works with other SCSI devices on the SCSI bus refer to the following section The Host Adapter and the SCSI Bus Installing your host adapter involves the following Terminating the SCSI bus Setting the S...

Page 31: ...l up to seven internal SCSI devices only The number of host adapters installed in your system is limited only by the number of available EISA slots that support bus master functions As with any standard bus the wires in a SCSI cable resemble transmission lines which can generate undesir able effects such as signal reflection and uneven loading of the line drivers To reduce these effects the SCSI b...

Page 32: ... other SCSI devices installed between the ends of the SCSI bus must have their terminators either removed or disabled Enabling or disabling host adapter termination is software selectable only The factory installed bus terminators on the AHA 2740 Series are enabled by default To disable termination on the host adapter refer to Chapter 3 Configuring the Host Adapter for instructions Refer to the SC...

Page 33: ...ith Pin 1 of the connectors on the host adapter and internal SCSI device 4 To connect a second internal SCSI device plug the middle con nector of the SCSI ribbon cable to the connector on the second internal SCSI device To connect additional internal SCSI devices to a SCSI bus you will need to obtain a 50 pin SCSI ribbon cable with enough connectors to accommodate all of your internal SCSI devices...

Page 34: ...er system Chapter 3 Configuring your Host Adapter provides a comprehensive description of how the utility works however the basic steps involved include the following 1 Run the EISA Configuration utility as instructed by the EISA system vendor 2 Copy the adp7771 cfg configuration file and adp7770 ovl over lay file needed to configure your host adapter with your EISA system from the diskette that c...

Page 35: ...host adapter is properly installed in your EISA system you will have to configure it as explained in Chapter 3 Configuring the Host Adapter To assist you with installation Figure 2 1 shows the location of all the connectors on the host adapter EXTERNAL LED CONNECTOR SCSI CHANNEL A INTERNAL CONNECTOR SCSI CHANNEL A EXTERNAL CONNECTOR SCSI CHANNEL B INTERNAL CONNECTOR AHA 2740T 2742T ONLY PIN 1 PIN ...

Page 36: ...er AHA Termination Internal and External devices AHA in between Removed Disabled Internal devices only AHA at end of cable Installed Enabled External devices only AHA at end of cable Installed Enabled Internal and External Devices When both internal and external SCSI devices are connected to the host adapter the last external device and the last internal device should be terminated as shown in Fig...

Page 37: ... the host adapter itself should be terminated as shown in Figure 2 4 HOST ADAPTER TERMINATION ENABLED INTERNAL DEVICE NO TERMINATION INTERNAL DEVICE TERMINATION ENABLED Figure 2 3 Internal Devices Only EXTERNAL DEVICE NO TERMINATION EXTERNAL DEVICE NO TERMINATION EXTERNAL DEVICE TERMINATION ENABLED HOST ADAPTER TERMINATION ENABLED Figure 2 4 External Devices Only Adaptec AHA 2740 Series User s Man...

Page 38: ...CSI Peripheral Devices Most SCSI devices use a jumper or a switch located close to their SCSI connector s On some SCSI devices you will have to physi cally remove resistor module s Refer to the manufacturer s docu mentation for instructions on enabling or disabling SCSI bus termination on your SCSI peripheral device s Note Some drives allow for the option of supplying termination power to their re...

Page 39: ... you are installing more than one SCSI host adapter each host adapter may be set to the same SCSI ID assuming they are on separate SCSI busses SCSI IDs 0 and 1 are best reserved for SCSI hard disk drives SCSI ID 0 is best reserved for the SCSI hard disk drive that will be used as you computer s boot device SCSI ID 1 is best reserved for a second hard disk drive SCSI ID 2 is often used for tape dev...

Page 40: ...puter system to expose the EISA bus slots on the motherboard 2 Locate an unused EISA slot in your system which supports bus master operations refer to the host computer system doc umentation for details and remove the corresponding slot cover 3 Carefully remove the host adapter from the antistatic bag Place the host adapter on top of the bag if you need to set it down 4 Align and insert the host a...

Page 41: ...unning non SCSI disk drives To connect the SCSI bus LED connector 1 Refer to your system s documentation to locate and unplug the LED cable from the connector on the system board 2 Connect the LED cable to the SCSI activity LED connector J1 on the host adapter as shown in Figure 2 5 Note On systems with a two position LED cable connect the LED cable to pins 1 and 2 of the LED connector LED CONNECT...

Page 42: ...I devices usually have two connectors and can be cabled to either the external connector on the host adapter or to the external connector of another external SCSI device SCSI devices are cabled together in a single continuous daisy chain of devices This chain may have no branches but must run from device to device in a continuous series If your host adapter includes both internal and external SCSI...

Page 43: ...ation is maintained throughout the bus Pin 1 of the SCSI cable is designated by a colored stripe on one edge of the ribbon cable Pin 1 of the host adapter or SCSI device connector is usually designated by a delta or arrow symbol on the connector Note Refer to the manufacturer s instructions to install and mount internal SCSI devices inside your computer chassis To connect internal SCSI devices 1 C...

Page 44: ...N 1 INTERNAL SCSI CONNECTOR COLORED STRIPE Figure 2 6 Connecting Cable to Internal Connector COLORED STRIPE PIN 1 INTERNAL SCSI DEVICE Figure 2 7 Connecting Cable to SCSI Device Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 2 17 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 Getting Started 2 17 ...

Page 45: ...a 50 pin shielded cable with a high density external connector External cable connectors are keyed and can only be plugged in one way Pin 1 orientation is automatic To connect external SCSI devices 1 Connect one end of the external cable to the host adapter external connector as shown in Figure 2 9 PIN 1 INTERNAL SCSI DEVICE COLORED STRIPE TO 1ST INTERNAL SCSI DRIVE TO HOST ADAPTER Figure 2 8 Conn...

Page 46: ... CABLE EXTERNAL CONNECTOR Figure 2 9 Connecting External Cable to Host Adapter EXTERNAL SCSI CABLE EXTERNAL SCSI DEVICE Figure 2 10 Connecting External Cable to SCSI Device Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 2 19 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 Getting Started 2 19 ...

Page 47: ...te Drives AHA 2742 2742T Only The floppy connector on the AHA 2742 2742T uses a 34 pin floppy ribbon cable with a 34 pin header connector Make sure to maintain Pin 1 orientation as described in previous section Connecting Internal SCSI Devices Note If you are not using the floppy controller on the AHA 2742 2742T be sure to disable it by removing the jumper shunt on Jumper J4 EXTERNAL SCSI CABLES E...

Page 48: ...e host adapter as shown in Figure 2 12 PIN 1 FLOPPY RIBBON CABLE FLOPPY CONNECTOR COLORED STRIPE Figure 2 12 Connecting Floppy Cable to Host Adapter Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 2 21 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 Getting Started 2 21 ...

Page 49: ...ond floppy drive Drive B as shown in Figure 2 14 COLORED STRIPE PIN 1 FLOPPY DISKETTE DRIVE Figure 2 13 Connecting Floppy Cable to Floppy Drive PIN 1 FLOPPY DISKETTE DRIVE COLORED STRIPE TO 1ST FLOPPY DRIVE TO HOST ADAPTER Figure 2 14 Connecting a Second Floppy Drive Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 2 22 Print Spec Number 491709 00 Rev C Current Date 9 1 93 E...

Page 50: ...s maintained 5 External SCSI devices are properly installed and cabled 6 If using the on board floppy controller on the AHA 2742 2742T the floppy diskette drive is connected to the host adapter with the 34 pin SCSI ribbon cable and that proper Pin 1 orientation is maintained 7 All system and power cables are properly connected Reassemble the System Refer to your system and SCSI device documentatio...

Page 51: ...Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 2 24 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 ...

Page 52: ...your EISA system The host adapter parameters that can be configured The options available to configure the host adapter BIOS and the devices connected to the host adapter The two utilities available in the EISA Configuration utility Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 3 1 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 3 1 ...

Page 53: ...Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 3 2 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 ...

Page 54: ...ter card Note Always refer to the documentation provided with your EISA system for instructions on adding and configuring adapter boards Depending on the EISA Configuration utility supplied with your system host adapter configuration will vary however the basic steps include Run the EISA Configuration utility Copy the configuration and overlay files Select the host adapter Configure the host adapt...

Page 55: ... to select among a number of options including copying new configuration files Select this option to copy the adp7771 cfg and the adp7770 ovl files from the host adapter diskette to either the bootable EISA configuration diskette or to the directory on your hard disk where the EISA Configuration utility is located If the Configuration utility does not provide such an option use the DOS Copy comman...

Page 56: ...elect a different IRQ for each host adapter installed Slot 1 Adaptec AHA 2470 AHA 2740T SCSI Host Adapter Host Adapter Interface Definitions Interrupt Level Bus Release Time Data FIFO Threshold BIOS Definitions Host Adapter BIOS Base Address IRQ 11 60 BCLKS 100 D8000H SCSI Channel A Configuration Host Adapter SCSI ID SCSI Bus Parity Check SCSI Selection Timeout SCSI Bus Reset at Power on SCSI Bus ...

Page 57: ... master mode Figure 3 3 displays your choices The default setting is 60 BCLKS Normally 60 BCLKS is optimum however if multiple bus master cards are installed in the system you may want to lower the value to free the EISA bus sooner Host Adapter Interface Definitions Interrupt Level IRQ 11 IRQ 9 IRQ 10 IRQ 12 IRQ 14 IRQ 15 Done F10 Edit Resources F6 Cancel ESC Figure 3 2 Selecting Interrupt Level A...

Page 58: ...ase Time 60 BCLKS 44 BCLKS 28 BCLKS 12 BCLKS 2 BCLKS Done F10 Edit Resources F6 Cancel ESC Figure 3 3 Selecting Bus Release Time Host Adapter Interface Definitions Data FIFO Threshold 100 75 50 0 Done F10 Edit Resources F6 Cancel ESC Figure 3 4 Selecting Data FIFO Threshold Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 3 7 Print Spec Number 491709 00 Rev C Current Date 9 ...

Page 59: ...e Configura tion utility will notify you if there is a conflict Note The BIOS must be enabled in order to boot from a SCSI fixed disk drive attached to the host adapter BIOS Definitions Host Adapter BIOS Base Address D8000H CC000H D0000H D4000H DC000H E0000H E4000H E8000H BIOS disabled Done F10 Edit Resources F6 Cancel ESC Figure 3 5 Selecting Host Adapter BIOS Base Address Adaptec AHA 2740 Series...

Page 60: ...rives If two host adapters are installed each would have its own SCSI bus thus each host adapter would still be set to SCSI ID 7 Refer to Chapter 2 Getting Started for additional information on SCSI ID SCSI Channel A Configuration Host Adapter SCSI ID 7 6 5 4 3 2 1 0 Done F10 Edit Resources F6 Cancel ESC Figure 3 6 Selecting Host Adapter SCSI ID Adaptec AHA 2740 Series User s Manual Stock Number 5...

Page 61: ...e the time in millisec onds used by the host adapter during the SCSI selection phase Fig ure 3 8 displays your choices The default setting is 256 milliseconds Lowering the SCSI Selection Timeout will speed up SCSI bus scans considerably however before lowering this value make sure that all the devices on the SCSI bus can respond to the shorter selection time SCSI Channel A Configuration SCSI Bus P...

Page 62: ...A Configuration SCSI Selection Timeout 256 milliseconds 128 milliseconds 64 milliseconds 32 milliseconds Done F10 Edit Resources F6 Cancel ESC Figure 3 8 Selecting SCSI Selection Timeout SCSI Channel A Configuration SCSI Bus Reset at Power on Enabled Disabled Done F10 Edit Resources F6 Cancel ESC Figure 3 9 Selecting SCSI Bus Reset at Power on Adaptec AHA 2740 Series User s Manual Stock Number 510...

Page 63: ...n termination BIOS and Device Configuration Select BIOS and Device Configuration to configure the BIOS and SCSI device options Figure 3 11 displays your choices SCSI Channel A Configuration SCSI Bus Termination Enabled Disabled Done F10 Edit Resources F6 Cancel ESC Figure 3 10 Configuring SCSI Bus Termination BIOS and Device Configuration BIOS configuration Device configuration ESC Figure 3 11 BIO...

Page 64: ...ll be treated as fixed disk drives Disabled No removable drives will be treated as fixed disks Software drivers are needed for drives not controlled by the BIOS Note Support for removable drives means only that the BIOS allows for use of a removable drive as if it were a fixed disk drive it does not mean that the disk media can be removed during operation BIOS Configuration Support Removable Disks...

Page 65: ...oss Support More than Two Drives This option allows you to enable or disable BIOS support for more than two SCSI hard disks supported by DOS 5 0 and above The default setting is disabled SCSI Device Configuration SCSI Device Configuration allows you to customize the configura tion of each SCSI device connected on the SCSI bus When this option is selected a screen similar to Figure 3 13 is displaye...

Page 66: ...ease may be realized if disconnect is not allowed in this case due to the decreased SCSI overhead In multi device environ ments disconnect should normally be enabled to take advantage of the disconnect reconnect feature If a particular SCSI device does not support disconnect reconnect then Enable Disconnection should be disabled set to no If a particular SCSI device does support disconnect reconne...

Page 67: ...be asynchronous Note Some older SCSI 1 devices may have trouble handling synchro nous negotiation which may result in erratic behavior or a hang condition For these devices set Initiate Sync Negotiation to no Maximum Synch Xfer Rate This option determines the maximum synchronous transfer rate MBytes sec that the host adapter will support The host adapter supports rates up to the Fast SCSI maximum ...

Page 68: ...g condition Include in BIOS Scan This option determines whether or not the host adapter BIOS sup ports devices attached to the SCSI bus without the need for device driver software When set to yes the host adapter BIOS controls the SCSI device When set to no the host adapter BIOS will not search the SCSI ID for devices to control device driver software is needed to con trol the SCSI device The defa...

Page 69: ...o power up SCSI devices one at a time when you boot your system Otherwise the devices will all power up at the same time When set to yes the SCSI Start Unit Command is sent to the SCSI device during boot up When set to no the SCSI device will power up in its normal fashion The default setting is no If this option is selected for more than one SCSI device the SCSI device with the lowest SCSI ID wil...

Page 70: ...enu The following section Utilities describes the two utilities available in the EISA Configuration utility Utilities Select Utilities from the EISA Configuration utility to access the two SCSI utilities that are available with your host adapter as shown in Figure 3 15 Save Abandon device configuration Save device configurations Abandon device configurations ESC Figure 3 14 Exiting SCSI Device Con...

Page 71: ...s MS DOS fdisk and format Most SCSI disk devices are pre formatted and do not need re formatting The Adaptec low level formatting utility is compatible with the vast majority of today s SCSI disk drives Caution All data on the drive will be lost when performing a low level for mat Be sure to back up your data before performing this operation AIC 7770 Utility Selection Options Disk Format Utility H...

Page 72: ...iagnostic Utility This utility runs a diagnostic on your host adapter by doing DMA transfers between the SCSI host adapter and system memory This test will run indefinitely until Esc is pressed Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 3 21 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 Configuring the Host Adapter 3 21 ...

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Page 74: ...ose prob lems that may occur when you install a host adapter in your system Problems you may encounter and how to fix them How to resolve conflicts with other options Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 4 1 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 4 1 ...

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Page 76: ...rnal peripheral power cables into a grounded line power outlet Follow the instructions in the hardware documentation 2 Be sure all cables are properly connected Check both power and SCSI interface cables See Installation in Chapter 2 3 Be sure the SCSI devices and host adapter on each SCSI bus are each set to different SCSI IDs See SCSI ID Setting in Chapter 2 4 Check SCSI bus termination The ends...

Page 77: ...o a unique SCSI ID which range from 0 to 7 See SCSI ID Setting in Chapter 2 3 Try enabling Include in BIOS Scan in the BIOS and SCSI Device Configuration option See Configure BIOS and SCSI Device in Chapter 3 4 Make sure the SCSI bus is properly terminated See Termination on the SCSI Bus in Chapter 2 5 You may need to low level format the SCSI hard drive If so first back up all data on the disk th...

Page 78: ...e problem and its solution Here are some of the more common Sense Key values and their meanings 02h Not ready The media is not ready to format Be sure that media is inserted in the drive and that the media is spun up 03h Medium error The disk media may be defective If it is a removable media drive try using a different media If it is a fixed disk drive the disk may be physically damaged 04h Hardwa...

Page 79: ...If this is not possible contact the manufacturer about possible work arounds I installed my host adapter board at IRQ12 and it does not work properly What is wrong Another device such as a mouse may be using IRQ12 Change the adapter board s IRQ to the default value 11 or to some other value See Configure the Host Adapter Parameters in Chapter 3 When I install my host adapter it either does not get...

Page 80: ...rect this problem 1 Change the IRQ settings with the EISA Configuration utility 2 Use the EISA Configuration utility to view BIOS addresses for the host adapter and if necessary change them Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 4 7 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 Troubleshooting 4 7 ...

Page 81: ...Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 4 8 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 ...

Page 82: ...e AHA 2740 Series host adapter EISA interface SCSI interface and floppy disk interface Pin assignments for the internal and external SCSI connectors Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page A 1 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 A 1 ...

Page 83: ...Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page A 2 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 ...

Page 84: ...er 1 Introduction Product Specifications Physical Dimensions Length 7 0 inches Width 0 625 inches Height 5 0 inches Standard EISA compatible form factor Power Requirements 5 0 0 25 Volts at 2 0 Amps maximum Environmental Requirements Temperature 0 55o C operating or storage Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page A 3 Print Spec Number 491709 00 Rev C Current Date 9 ...

Page 85: ...gle ended operation Output Signals All signals use open collector or three state drivers Each signal driven by a SCSI device has the following output characteristics when measured at the SCSI device s connector Table A 2 Output Signals Signal Definition Characteristics VOL Low level output voltage 0 0 to 0 5 volts DC at 48 mA sinking signal assertion VOH High level output voltage 2 5 to 5 25 volts...

Page 86: ...ut current 0 0 to 0 1 mA at V1 2 7 volts DC Minimum input hysteresis 0 2 volts DC Maximum input capacitance 25 pF measured at the device connector closest to the stub if any within the device Internal SCSI Connector The internal SCSI connector must be an unshrouded 50 pin header compatible with unshielded Alternative 1 connector as specified in ANSI X3 131 1986 Table A 4 lists the pin assign ments...

Page 87: ...ound 22 Ground 23 Ground 24 Ground 25 Open 26 Term Power Fused 27 Ground 28 Ground 29 Ground 30 Ground 31 Ground 32 ATN 33 Ground 34 Ground 35 Ground 36 BSY 37 Ground 38 ACK 39 Ground 40 RST 41 Ground 42 MSG 43 Ground 44 SEL 45 Ground 46 C D 47 Ground 48 REQ 49 Ground 50 I O Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page A 6 Print Spec Number 491709 00 Rev C Current Date 9...

Page 88: ...nd 28 DB 2 4 Ground 29 DB 3 5 Ground 30 DB 4 6 Ground 31 DB 5 7 Ground 32 DB 6 8 Ground 33 DB 7 9 Ground 34 DB P 10 Ground 35 Ground 11 Ground 36 Ground 12 Ground 37 Reserved 13 Open 38 Term Power Fused 14 Ground 39 Reserved 15 Ground 40 Ground 16 Ground 41 ATN 17 Ground 42 Ground 18 Ground 43 BSY 19 Ground 44 ACK 20 Ground 45 RST 21 Ground 46 MSG 22 Ground 47 SEL 23 Ground 48 C D 24 Ground 49 REQ...

Page 89: ... Receiver Input Signals VT 1 0 volts maximum VT 1 4 volts minimum Tied to 5 volt supply through 150 ohm resistors Schmitt Trigger with 0 8 volt hysteresis Connector The floppy disk interface connector should be an unshrouded 34 pin header Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page A 8 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 AHA 2740 Serie...

Page 90: ...her or not you need additional software for your host adapter in the DOS Windows environment Information on Adaptec s EZ SCSI I O Operating Environment Software that makes driver installation easier than ever before Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page B 1 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 B 1 ...

Page 91: ...Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page B 2 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 ...

Page 92: ...ter 1 Introduction DOS Windows Under MS DOS 5 0 or higher up to seven SCSI hard disk drives per host adapter eight total can be connected without additional software older versions of DOS support up to two hard disk drives Additional software is required if you desire to do any of the following Support more than two fixed disk drives under versions of DOS prior to MS DOS 5 0 Support more than eigh...

Page 93: ...vice driver which supports up to 24 fixed disk devices To install support for SCSI devices other than fixed disk devices and CD ROM drives check the hardware documentation for those devices If the device requires ASPI support you first need to run Adaptec EZ SCSI to install an ASPI manager and then install any other software provided with the device If the device is designed to interface directly ...

Page 94: ...this appendix to find out How to optimize your system s performance after installing the host adapter Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page C 1 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 C 1 ...

Page 95: ...Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page C 2 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 ...

Page 96: ...request for it you may want to disable synchronous negotiation See Configure BIOS and SCSI Device in Chapter 3 Note Even when synchronous negotiation is disabled on the host adapter the host adapter will still switch to synchronous mode if it receives a request from the SCSI device Disabling the Host Adapter BIOS Disabling the host adapter BIOS saves you 16 KBytes of memory address space and can a...

Page 97: ...you set Enable Disconnection to no when there is only a host adapter and a single disk device on the SCSI bus You should set this option to yes however if you have more devices on the SCSI bus See Configure the BIOS and SCSI Device in Chapter 3 Send Start Unit Command This option which is supported by some SCSI devices reduces the load on your computer s power supply by allowing the host adapter t...

Page 98: ...ance Adaptec s EZ SCSI I O Operating Environment Software is designed not only to simplify installation of device drivers under DOS but also includes ASPI management software to provide Vir tual DMA Services VDS support and enhanced Windows support The drivers that are installed will give DOS users the best perfor mance possible under not only DOS but Windows Adaptec AHA 2740 Series User s Manual ...

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Page 100: ...of extended translation and the DOS 1 GByte limit When to use the extended translation feature Questions and answers about extended translation Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page D 1 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 D 1 ...

Page 101: ...Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page D 2 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 ...

Page 102: ...ature refer to Configure BIOS and SCSI Device in Chapter 3 The DOS 1 Gigabyte Limit All versions of DOS are limited to 1024 cylinders per drive The standard translation scheme for SCSI host adapters using 64 heads and 32 sectors provides a maximum accessible capacity of 1 GByte To eliminate the 1 GByte limit Adaptec s new extended transla tion feature uses 255 heads and 63 sectors extending the di...

Page 103: ...sing standard translation Note UNIX is understood to be AT T USL all versions SCO v3 2 4 or later and ISC v3 0 or later Using Fdisk To install a new disk or to re partition an existing disk use the fdisk DOS utility as you normally would The cylinder size increases to 8 MBytes when you enable extended translation The size of the parti tion you request must therefore be a multiple of 8 MBytes If yo...

Page 104: ...ixed disk drives on the host adapter You can use up to seven fixed disk drives under the BIOS provided you are running DOS 5 0 What if I use older versions of software drivers when extended translation is enabled To protect your data the host adapter will lock out any driver that does not identify itself as capable of extended translation If you need to use software that is not compatible with ext...

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Page 106: ...his manual Definitions of terms commonly used in other documents and publications which discuss the SCSI to microcomputer peripheral connection Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page G 1 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 Glossary 1 ...

Page 107: ...Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page G 2 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 ...

Page 108: ...e that provides an interface between ASPI mod ules a host adapter board and the SCSI devices connected to the adapter A single ASPI manager can handle multiple I O requests from multiple ASPI modules ASPI managers are written for a specific operating system such as DOS OS 2 or UNIX and a specific family of host adapter boards Asynchronous Data Transfer A data transfer method that involves interloc...

Page 109: ...ivity in the SCSI peripheral device target to which it is addressed Bus Mastering A high performance method of data transfer in which the host adapter s on board processor handles the transfer of data directly to and from a computer s memory without intervention from the computer s microprocessor This is the fastest method of data transfer available for multi tasking operating systems Adaptec s AH...

Page 110: ...such as fixed disk drives and CD ROM drives Each kind of device requires a different driver Device driver pro grams are stored on a PC s fixed disk and are loaded into memory at boot time Differential A term referring to the electrical characteristics of the signals used on the SCSI bus interface Differential signals occupy two conductors with a positive and negative polarity component of the sign...

Page 111: ... network cards video adapters and modems to transfer data across the PC bus 32 bits at a time This standard was introduced in 1988 EISA Configuration The operation of configuring a device on the EISA bus through accessing registers in the device by the host This replaces the method of using jumpers commonly found on ISA bus devices EPROM Erasable Programmable Read Only Memory An integrated circuit...

Page 112: ...apter Host Adapter A printed circuit board or integrated circuit that installs in a standard microcomputer system and provides a SCSI bus connec tion so that SCSI devices can be connected to the microcomputer I IBM PC AT Compatible Any computer system that emulates exactly the IBM PC AT and that uses an ISA backplane bus Industry Standard Architecture See ISA Initiator A SCSI device that requests ...

Page 113: ...at a time Expansion devices are plugged into sockets in the PC s motherboard ISA is sometimes called the AT bus because it was originally introduced with the IBM PC AT in 1983 K KByte Kilobyte A measure of computer storage One KByte equals 1024 bytes A byte is the amount of storage needed to hold one character L Logical Unit A physical or virtual device addressed through a target Each target can h...

Page 114: ...ting in parallel Multi threaded I O A method by which data is accessed simultaneously from multiple SCSI devices to increase a system s data transfer rate For exam ple if the system needs data from two disk devices it requests data from the first device which temporarily disconnects from the SCSI bus while it is seeking the data During this delay the system requests data from the second device and...

Page 115: ...d overhead SCB SCSI Control Block The mechanism used in emulation mode to transfer control information to and from the board SCSI Small Computer Systems Interface A bus interface standard that defines physical and electrical characteristics for hardware devices SCSI provides a standard interface that enables many different kinds of devices such as disk drives magneto optical disks CD ROM drives an...

Page 116: ...nded grounding Some SCSI devices use a differential grounding scheme These devices are not supported by the AHA 2740 Series Differential devices may be damaged if you connect them and the AHA 2740 Series to the same SCSI bus Single Threaded Operation Operation of the computer system such that only one program can be operating or active at a time The system must wait until all resources are availab...

Page 117: ...pheral device such as a disk drive perform ing a service for an initiator The target may also be a host adapter performing a processor type device service for an initiator Termination A physical requirement of the SCSI bus The devices at the physi cal ends of the SCSI bus must have terminating resistors either installed or enabled devices in the middle of the bus must have terminating resistors ei...

Page 118: ...7 3 8 4 3 4 7 configuration 3 12 3 13 disabling C 3 error if device not found 3 18 extended translation support 3 14 D 1 D 5 include in BIOS scan 3 17 partitioning support 1 6 removable disk drive 3 13 3 17 support for more than two drives 3 14 Board layout 1 6 Boot device 1 7 4 4 Booting your system 3 18 C 4 Bulletin Board Service BBS 1 9 Burst rate 1 3 Bus See SCSI bus Adaptec AHA 2740 Series Us...

Page 119: ...also EISA configuration utility host adapter 2 7 3 1 3 19 3 21 overlay file 2 7 3 3 3 4 overview 3 3 parameters 2 7 3 5 SCSI device 3 14 Configuration chip 1 7 Connectors external 1 7 2 6 2 15 A 7 floppy 1 7 2 7 2 8 A 8 internal 1 7 2 6 2 15 A 5 LED 1 7 2 8 2 14 location 2 8 SCSI channel A 1 7 2 8 SCSI channel B 1 7 2 8 CPU 1 3 1 4 Customer support See Technical support Adaptec AHA 2740 Series Use...

Page 120: ...7 3 3 3 4 exiting 3 19 running in monochrome mode 4 4 EISA slot 2 4 2 6 2 7 2 13 3 4 Enable disconnection 3 15 C 4 Error if device not found 3 18 Error message 3 18 Extended translation 1 7 3 14 D 1 D 5 EZ SCSI See Adaptec EZ SCSI F Fdisk command D 4 Features 1 4 FIFO 1 7 3 7 Floppy disk drive 2 15 2 20 A 8 connector 1 7 2 7 2 8 controller 1 4 1 7 2 7 disabling the drive 1 8 2 20 Adaptec AHA 2740 ...

Page 121: ...isk media 3 20 Host adapter BIOS See BIOS Host adapter diagnostics 3 21 See Utilities Host adapter support B 3 I I O operating environment B 1 D 4 DOS Windows B 3 C 5 ID See SCSI ID Initiate sync negotiation 3 16 Installation for experienced users 2 5 for new users 2 8 host adapter 2 6 2 13 overview 2 3 SCSI device 2 6 Interrupt level 1 7 3 5 See also IRQ IRQ 1 7 3 5 4 6 4 7 conflicts with 4 6 Ada...

Page 122: ... P Parameters 2 7 3 5 Parity 1 7 3 10 C 4 Partitions D 4 Performance tips C 3 PhaseEngine 1 3 Power requirements A 3 R RAM 1 7 Removable disk drive 1 7 3 13 3 17 4 6 See also Hard disk drive See also SCSI device Reset 1 7 Reset at power on 3 11 Ribbon cable 2 16 Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page I 5 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Dat...

Page 123: ... termination 2 10 3 12 SCSI ID 1 7 2 4 2 5 2 12 3 9 3 14 3 18 4 3 conflicts 2 12 for boot drive 4 4 SCSI termination 1 7 2 4 2 5 2 9 2 11 3 12 4 3 4 4 4 6 disabling on the host adapter 2 11 resistor module 2 11 terminators 2 5 Selection phase 3 10 Selection timeout 1 7 3 10 Send Start Unit command 3 18 C 4 Sequencer 1 3 Signal reflection 2 4 Specifications A 1 A 7 Static electricity 1 8 2 13 Synch...

Page 124: ...Channel 2 4 U Unpacking and inspecting 1 8 Utilities 3 19 Adaptec EZ SCSI B 4 disk format 3 20 4 4 host adapter diagnostics 3 21 low level format 3 20 4 4 4 5 D 1 D 5 W Windows B 3 C 5 Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page I 7 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 Index Index 7 ...

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Page 126: ...Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page I 9 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 ...

Page 127: ...Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page I 10 Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 ...

Page 128: ...gs 1 7 The On board Floppy Controller AHA 2742 2742T Only 1 8 Unpacking and Inspection 1 8 Adaptec Technical Support 1 9 2 Getting Started About This Chapter 2 1 Installation Overview 2 3 The Host Adapter and the SCSI Bus 2 4 Quick Installation 2 5 Prepare Your SCSI Devices 2 5 Install Your Host Adapter and Peripherals 2 6 Configure the Host Adapter 2 7 Installation 2 8 Termination on the SCSI Bus...

Page 129: ...Format Utility 3 20 Host Adapter Diagnostic Utility 3 21 4 Troubleshooting About This Chapter 4 1 SCSI Troubleshooting Checklist 4 3 Problems and Solutions 4 4 Conflicts With Other Options 4 7 APPENDICES A Specifications About This Appendix A 1 Technical Information A 3 Product Specifications A 3 Extended Industry Standard Architecture Interface A 4 SCSI Interface A 4 Electrical Interface A 4 Flop...

Page 130: ...rmance C 5 D Disk Drives Over 1 Gigabyte About This Appendix D 1 Extended Translation Using DOS 5 0 D 3 The DOS 1 Gigabyte Limit D 3 When to Use Extended Translation D 4 With DOS Version 5 Only D 4 Drives With Mixed Partitions D 4 Using Fdisk D 4 Questions and Answers About Extended Translation D 5 Glossary About This Glossary Glossary 1 Glossary Glossary 3 Index Index 1 Adaptec AHA 2740 Series Us...

Page 131: ...e 2 14 Connecting a Second Floppy Drive 2 22 Figure 3 1 Host Adapter Parameters 3 5 Figure 3 2 Selecting Interrupt Level 3 6 Figure 3 3 Selecting Bus Release Time 3 7 Figure 3 4 Selecting Data FIFO Threshold 3 7 Figure 3 5 Selecting Host Adapter BIOS Base Address 3 8 Figure 3 6 Selecting Host Adapter SCSI ID 3 9 Figure 3 7 Selecting SCSI Bus Parity 3 10 Figure 3 8 Selecting SCSI Selection Timeout ...

Page 132: ...d Physical Interface A 4 Table A 2 Output Signals A 4 Table A 3 Input Signals A 5 Table A 4 Internal Connector Pin Assignments A 6 Table A 5 External Connector Pin Assignments A 7 Table A 6 Output and Input Signals A 8 Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 0 ix Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 Table of Contents ix ...

Page 133: ...Adaptec AHA 2740 Series User s Manual Stock Number 510381 00 Rev C Page 0 x Print Spec Number 491709 00 Rev C Current Date 9 1 93 ECN Date 9 14 93 ...

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