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page 6.2

System Memory

General

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The memory cards contain the main user-accessible dynamic RAM and associated
timing and multiplexing circuitry. These cards interface with the system through
one of the parallel I/O connectors located on the backplane board. Connection
with the cards is implemented through the use of a 64-pin edge connector which

is an integral part of the cards. A configuration jumper on these cards enables
up to two blocks (two cards) of memory to be designated as residing in the system.

Specifications

Your computer comes with a minimum of 128 kilobytes of RAM but may contain
up to 640K if additional banks and a second memory card have been installed.
One bank of memory consists of nine dynamic RAM integrated circuits. Eight
of the chips store data, and one chip in each bank is used for a parity check

of stored data.

As presently configured, memory may be added in increments of one bank of

64 kilobit chips (64 kilobits times 8 chips equals 64 kilobytes per bank). This
allows 320 kilobytes to reside on one memory card if all five banks are installed,
and an additional 320 kilobytes may reside on a second card.

When 256 kilobit RAM ICs become readily available, it will be possible to install
the entire 640 kilobytes on one memory card. The system will accept this configura-
tion only if U455, the memory address decoder, is replaced. This memory address
decoder provides the address logic required by the higher capacity chips. The

replacement U455 device will be made available when it is determined that reliable,
economical, 256K devices are feasible.

The memory configuration is an 8-bit data structure, with odd parity generation

and error detection, to detect even-numbered bit producing errors.

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Summary of Contents for Z-100 Series

Page 1: ...P rogramm e r s Reference Manual I I data systems...

Page 2: ...P rogramm e r s Reference Manual Z 100 PC Series Computers fAPIFH data systems...

Page 3: ...Rights data provisions TrademarksandCopyrights Zenith is a registered trademark of Zenith Electronics Corporation Z 100 andZ DOSaretrademarks o Zenith Data SystemsCorporation Copyright C 1984byZenith...

Page 4: ...al Keys System Memory and I O Address Maps Interrupt Vectors Support Packages System Operating Features 2 1 22 22 2 3 2 5 2 5 2 7 2 7 2 16 2 17 2 19 2 21 Chapter 3 Introduction System Layout Central P...

Page 5: ...ncreasing Keyboard Buffer Size Keyboard 5 1 5 2 5 4 5 18 Chapter 6 Introduction General Specifications DIP Switches Configuration Jumpers Theory of Operation Memory Access Operations Address Multiplex...

Page 6: ...terface Information Video Interrupt Vector FunctionCode 0 Set Video Mode Function Code I Select Cursor Type Function Code 2 Select Cursor Position Function Code 3 Read Cursor Position Function Code 4...

Page 7: ...eive Character from the Serial Port Function Code 3 Read Communications Status d Parallel Input Output 8 1 8 2 8 2 8 2 8 3 8 4 8 4 8 7 8 7 8 8 8 8 8 9 8 10 8 10 0 Disk Drives 9 1 92 92 9 3 9 3 9 5 9 6...

Page 8: ...pad Special Keys Memory Card Select Jumper Locations Memory Access Block Diagram Video Card Jumper Locations C haracter ROM Contents Character Attribute Format Graphics Storage Map Medium Resolution M...

Page 9: ...ect Logic 6 2 System Memory Map 6 3 Parity Disable Output Port Values 7 1 Power Up Character Font Selection 7 2 Monochrome Character Attribute Selection 7 3 Color Attribute Byte Logic 7 4 Color Select...

Page 10: ...down Serial Byte 2 Breakdown Serial Byte 7 Breakdown Parallel Device Operation Codes Serial Device Operation Codes Mode Select Byte Breakdown Word Length Selection Parity Selection Baud Rate Selection...

Page 11: ......

Page 12: ...nit Cathode Ray Tube Cydic Redundancy Check Clear to Send Dual I nline Package Direct Memory Access Disk Operating System Data Set Ready Error Correction Code Integrated Circuit Input Output Least Sig...

Page 13: ......

Page 14: ...with MS DOS Also as part of this manual set the iAPX 88 Book from Intel is induded to provide you with a complete comprehensive description of the Intel 8088 and its instruction set Since most of the...

Page 15: ...46 7 x 19 0 x 3 5 cm 168 watts 5V 16 4A maximum 12V 5 4A maximum 12V 25A maximum 12V regulated 1 5A maximum 100 130 VAC or 200 230 VAC switch selectable input Intel 8088 or Harris 80C88 8 16 bit micro...

Page 16: ...udio One 8 ohm 2 inch speaker Mass Storage One or two 5 25 inch double sided double density 40 track floppy disk drives MS DOS Version 2 maximum capacity of 360K per disk MS DOS Version 1 25 maximum c...

Page 17: ......

Page 18: ...ion concerning the built in features of your computer with emphasis on those which will be of primary use in programming the various features and functions Among the items covered are the following Mo...

Page 19: ...keyboard initiated manual boot Refer to the Configuration section in Chapter 4 for DIP switch setup instructions NOTE Also available is the Disk Based Diagnostics for the Z 100 PC Series Model CB 5063...

Page 20: ...ced by a qualiTied individual ERROR RAM failure Address XXXX YYYY Bit N Chip UXXX t t ERROR Parity ha rdware failure Add ress XXXX YYYY Bit N C hip U XXX I ERROR Parity failure Ad dress XXX X YYYY Chi...

Page 21: ...disk controller card but may also be caused by other defective cards in the system If any nonstandard cards have been installed they should be suspected first in an error condition of this nature DIS...

Page 22: ...er RAM plus the 16 kilobytes of video screen RAM Selecting a Test Tests may be performed by entering TEST at the system prompt arrow The following menu will appear on the screen CHOOSEONE OF THE FOLLO...

Page 23: ...r of the screen The test count is displayed in the center of the screen To end the test press theESCkey The count will stop and the messageTYPE ESC TOEXIT will appear at the bottom of the screen Press...

Page 24: ...em from a disk drive Display the contents of memory Execute a program Set program breakpoints Input or output values to or from VO ports Search memory f o raby t ep attern Disassemble user program mem...

Page 25: ...s I 2 3 or 4 with the default set by the PART program Example BF3 RETURN In this example the system will boot the operating system from floppy disk drive number 3 Command Color bar Syntax C Purpose Pa...

Page 26: ...e system prompt Example EO 100 RETURN This will cause the address 0000 0100 to be printed followed by the contents of that memory address The flashing cursor will indicate that the computer is waiting...

Page 27: ...is executed the program will stop and the contents of the user registers will be shown Entering just G will cause the program to pick up where it left off with no breakpoints Command Hexadecimal Math...

Page 28: ...ites a value to the specified port address Example 021 BCRETURN In this example the computer will write the value OBCH to output port 21H Command Examine registers Syntax Rlregister aaue Purpose Exami...

Page 29: ...ven flag register any of the abbreviations may be entered at the R user input prompt Example NGPOBFlfRN This will cause the computer to set the Sign flag and reset the Parity flag If more than one abb...

Page 30: ...t is one execution The default address is the current address Example T 011A 10 RETURN This causes ten instructions in the current program segment to be executed and register contents displayed starti...

Page 31: ...ut 40 columns x 25 rows color at the RGBoutput 80 columns x 25 rows monochrome at the RGBoutput Single text pages may be hardware scrolled without affecting other 80 columns x 25 rows color at the RGB...

Page 32: ...Information is scrolled by actually moving screen memory contents Also the default scrolling mode Hardware jump scrolling Incompatible with some applications packages but faster than the software mode...

Page 33: ...orCTRI C CTRL ALT RETURN Halts computer operation until any other non control key is pressed Terminates any executing command and returns control to user A 3 key combination which results in a system...

Page 34: ...raphics Reserved Color Graphics Reserved Reserved for Bit Mapped Video Graphics Card MFM 150 Monitor Scratchpad RAM Winchester Drive Buffer System ROM FOOOO F3FFF 00000 4FFFF 50000 9FFFF A0000 AFFFF B...

Page 35: ...DDRESSRANGE DEVICE 000 OOF 020 021 040 043 060 063 080 083 DMA Processor Interrupt Generator System Timer PPI Status Port DMA PageRegisters Non Maskable Interrupt NMI Enable Register Diagnostic LEDs R...

Page 36: ...arious assembly level programming operations Table 2 8 Program Interrupt Vectors VECTOR FUNCTION Divide by 0 Single Step Non Maskable Interrupt Breakpoint Overflow Print Screen Not used Not used 8 9 A...

Page 37: ...Boot operating system Set read time of day In addition several special vectors are recognized as defined by Table 2 11 Table 2 11 Special Interrupt Vectors VECTOR FUNCTION 0 IB IC ID IE IF Keyboard b...

Page 38: ...in cards and the various program ming languages applications and utility packages available for your computer from Zenith Data Systems These options include detailed implementation of many of the prog...

Page 39: ......

Page 40: ...erent elements that make up the computer system The information contained in this chapter is intended as a general overview of the system only It provides preparatory material for the chapters which f...

Page 41: ...VE FLOPPY DISK CONTROLLER POWER SI PPLY WINCHESTER DRIVE CONTROLLER KEYBOARD CPU SYSTEM I O BUS SYSTEM MEMORY OPTIONAL CARDS VIDEO GRAPHICS SERIAL RS 232 INTERFACE SERIAL DEVICE PARALLEL I N T E R F A...

Page 42: ...rations ordinarily performed by the 8088 under software freeing the 8088 to other tasks such as controlling informa tion flow The main advantage of adding the coprocessor is an apparent increase in sp...

Page 43: ...A6 A7 A8 A9 AIO All AEN I O CHCK4 D7 D6 D5 D4 D3 D2 Dl DO I O CHRDY VO channel check Provides the CPU with parity error status for memory or other I O devices Active low indicates error Data bit 7 Dat...

Page 44: ...VDC bus Interrupt request 2 Not used Available for assignment to a user selected device 5VDCbus DMA request 2 Assigned to floppy disk controller 12VDCbus No connection 12 VDC bus Ground Memory write W...

Page 45: ...terrupt request 6 Assigned to floppy disk controller Interrupt request 5 Assigned to Winchester drive controller Interrupt request 4 Assigned to Serial port I fixed Interrupt request 3 Assigned to Ser...

Page 46: ...ough the built in ROM routines or by means of iAPX 88 assembly level instructions The instruction set and programming information for the 8088 microprocessor are detailed in the iAPX 88 Book included...

Page 47: ...fer to Figure 4 1 for the location of SW1 and SW2 the two 8 section DIP switch packages These two switches when properly configured will indicate to the system whether floppy disk drives are present a...

Page 48: ...Table 4 1 for the proper switch settings for your system TOP OF CARD FLOPPY DRIVES AT T ACHED 8 087 COP R O C ES S O R INS T A L L E D 0 1 a LEFT RIGHT BASE SIZE OF MEM OR Y D EVICES BOTTOM OF CARD 2...

Page 49: ...er options reserved 4 5 Right Left Left Right 6 7 Right Right Left Right Right Left 0 Number of Floppy Drives Floppy Drives Present Section 0 of switch SWI indicates the presence or absence of floppy...

Page 50: ...rned on Position these sections to the desired configuration for either 40 or 80 character line length Number of Floppy Drives Sections 6 and 7 indicate the number of floppy disk drives present in the...

Page 51: ...eft Rig ht Right L e ft Left Left 0 M onitor 60 Hz Screen R efresh 50 Hz Frequency Memory Size The first five sections of SW2 tell the system how much user memory you have Don t forget to change thes...

Page 52: ...Unit Monitor Sync Frequency Section 7 of SW2 tells the CPU at what vertical sync frequency the monitor should run Select the position that corresponds to your AC power line frequency Nor mally this wi...

Page 53: ...rupt is implemented the contents of the screen are dumped to an attached printer Only valid characters will be printed Graphics containing characters not recognized by the printing device will be igno...

Page 54: ...Monochrome on the color card 80 x 25 Monochrome on the color card RGB output 80 x 25 Monochrome on themonochrome card Monochrome output Number of floppy drives bitvalue plus I if bit 0 is set I drive...

Page 55: ...day the contents of AL will NOT be 0 otherwise it will be 0 To set the time the desired high count is placed in the CX register and the low count in DX The contents of AH must NOT be 0 when the interr...

Page 56: ...one of three different ways Puls e train generated by toggling a program control register bit The o utput of Channel 2 of the timer counter programmed to deliver a Cloc k input to the timer counter m...

Page 57: ......

Page 58: ...Chapter 5 Keyboard Introduction The keyboard entry point permits an application program to determine the status of the keyboard or to receive characters entered through the keyboard...

Page 59: ...function to be performed 0 Getacharacter from the keyboard 1 Determine if a key code is waiting in the keyboard s buffer 2 Return the keyboard s shift status To use this interrupt load the desired ope...

Page 60: ...lag will be false AL will contain the ASCII code AH will contain the scan code Character will remain in the keyboard Character Entered buffer The 0 flag will be true Character Not Entered Returns the...

Page 61: ...that the CAPS LOCK key affects only the alphabetic keys All other keys are unaffected by its action A small red light in the key indicates the function of the CAPS LOCK key If the light is on the fun...

Page 62: ...177H 2D78H 1579H 2C7AH IE41H 3042H 3E43H 2044H 1245H 2146H 2247H 2348H 1749H 244AH 254BH 264CH 324DH 314EH 184FH 1950H 1051H 1352H IF53H 1454H 1655H 2F56H 1157H 2D58H 1559H 2C5AH IEOIH 3002H 2E03H 200...

Page 63: ...affect the operation of these keys and is therefore not listed in Table 5 3 which lists the codes produced by each key Again the ASCII code is the least significant byte of the scan codes shown Note...

Page 64: ...T ALTERNATE 0231H 0221H 7800H 0332H 0340H 0300H 7900H 0433H 0423H 7AOOH 0534H 0524H 7BOOH 0635H 0625H 7COOH 0736H 075EH 071EH 7DOOH 0837H 0826H 7EOOH 0938H 092AH 7FOOH OA39H OA28H 8000H OB30H OB29H 81...

Page 65: ...Page 5 8 Keyboard Table 5 3 continued Nonalphabetic Key ScanCodes NOT SHIFTED SHIFT CTR L ALT SHIFTED CON TROL ALT ERNATE KEY TOP 2822H 2827H 333CH 332CH 343EH 342EH 353FH 352FH 2B7CH 2BlCH 2B5CH...

Page 66: ...control keys are shown in Figure 5 3 the scan codes and the usual software function are listed in Table 5 4 E3 F 2 Fj F j W E R T Y U I 0 P 8 9 6 A 8 D F G H J K L 8 5 6 26 F 6 Fj F8 O oo FF Fj j Fig...

Page 67: ...0 cjj cjj 0 cjj 0 E 0 R cjj cd cn Z 0 cn cd cjj cn 0 0 C 0 QJ cn C 0 0 O 0 cn cn 9 O d O cjj cn cn 2 D cn cjj cjoy OW L a oI X c jj f Fv O cjj 0 cn cjj j i L cjj 0 c J 0 Q o x D x a x cD D x3 D D cD...

Page 68: ...ted in Table 5 5 Note that the keypad special functions are shown in this figure and table along with the codes for the numeric function although they are not specifically called out in the Usual Func...

Page 69: ...0 0 c o 0 a o 0 o o a 4 M Cr M x W h M M M a a a a a a a a a g D 3 o g c z K I 0 a a 0 6 a e I 5 0 X X OXX O O O O SS O O O O oo m C oo M O tQ 8 C O CD CD CO CO CD CD CD F t 0 x 8 X X X K X X K X X X...

Page 70: ...Page5 13 Keyboard...

Page 71: ...page5 14 Keyboard 0 a o o o 4 z 0 P 44 9p o o 5 x D x C x C O C C C 0 x CD C j a...

Page 72: ...Page 5 15 Keyboard...

Page 73: ...of the hexadecimal code you wish to generate Then release the ALT key When the ALT key is released the conversion takes place and the hexadecimal code is generated FI FF FA FI FF FF 0 W E R T Y U I 0...

Page 74: ...ces the same scan codes as the RETURN key 1CODH in the shifted and unshifted modes and 1COAHwhen used with the CIRL key and is usually used in the same way 4 Fl FF 0 W E R T Y U I 0 P 7 8 9 FS F Fs FS...

Page 75: ...egment address for the proper block of memory Set the word variable at 40 1A 40 1C and F000 CA to the starting offset of the new keyboard buffer Set the word variable at F000 CC to the offset of the l...

Page 76: ...m emo ry DATA SEGMENTSEGMENT AT 40H KEY AD EQU 1AH KEY TAILPTR EQU 1CH D ATASEGM ENT END S Compatible data segment Buffer head pointer Buffer tail pointer CODE SEGMENTPUBLIC ASSUME CS CODE DS D ATA S...

Page 77: ...XE2BINBIGKBUFF EXE CO M The MASM file is only on the Programmer s Utility Pack distribution disk The LINK and EXE2BIN files are both on the second distribution disk of MS DOS You should not see any er...

Page 78: ...nd descriptive material related to programming operations as they apply to the system memory RAM banks Refer to the information in Chapter 2 under ROM Diagnostics which applies to memory access and ma...

Page 79: ...s store data and one chip in each bank is used for a parity check of stored data As presently configured memory may be added in increments of one bank of 64 kilobit chips 64 kilobits times 8 chips equ...

Page 80: ...hese switches for your system Configuration Jumpers J401 is a configuration jumper located on the memory card used as a card select jumper If only one memory card is installed J401 should be positione...

Page 81: ...Page 6 4 System Memoly mi gg im mm MEMORY CARD Figure 6 1 Memory Canl Select Jumper locations...

Page 82: ...the general functional description of the memory circuits which follows BMEMW READ WRITE MEMR TIMER ENCODER RASTIM CASTIM MUXTIM WE MEMW A16 A19 RASO RAS4 SYSTEM RAM CASO CAS4 CAS CYCLE CASGATE O AEN...

Page 83: ...is read During an actual refresh cycle all rows in all banks are read simultaneously automatically refreshing them The parity RAMs are also 6665 or 4164 ICs One of these chips in each bank supplies s...

Page 84: ...e least significant bit LSB in the byte To understand how memory is accessed you must first understand how the mem ory chip itself is structured Each dynamic RAM IC is capable of storing 65 536 64K I...

Page 85: ...nal on the memory card which determines whether the memory card is the first or second card in the system Data Buffer The memory cards also contain a three state 8 bit data buffer interfacing the syst...

Page 86: ...he bank where that piece of data resides Upon a read retrieval the 9 bit word residing at that address is again checked for odd parity If a data loss which produces an even number of bits such as an e...

Page 87: ...buffer System ROM Memory addresses can range from 0 to 9FFFFH 0 to 655359 decimal although your system may not contain that much memory For instance if you have a basic system the addressable range f...

Page 88: ...to another Using RAM contents to control video graphics In addition to normal RAM manipulation you have the ability to disable parity generation and or checking either for diagnostic checks of the sy...

Page 89: ...hest and lowest usable segment value are determined by the memory address in question For our example address the lowest usable segment value would be 34F1H since anything lower would result in an off...

Page 90: ...and position selection Use of the monitor as a simple terminal Retrieval of screen memory information The video card provides an interface between your computer and various display output devices such...

Page 91: ...n Jumpers This section describes the optional functions obtainable through the positioning of the configuration jumpers located on the video card When using the following instructions if you need to a...

Page 92: ...Page 7 3 Video GraphicsProgramming A VIDEO CARD VIDEO CARD Figure 7 1 Video Card Jumper Incations...

Page 93: ...which represent them J302 and J305 are the character type selection jumpers The condition of these jumpers is polled when you first turn on your computer and will determine whether the characters fro...

Page 94: ...Page7 5 Video Graphics Programming E a Q oo A B R e 0 A 0 0 0 N F 0 U A e 0 I 2 V4 A 1 N 0 0 Figure 7 2 Character ROM Contents...

Page 95: ...vertical sync polarity required by your internal monitor Z 160 models positive or negative Position J307 to the markings which correspond to the horizontal sync polarity required by your external RGB...

Page 96: ...on an RGB CRTdisplay and levels of gray on a monochrome monitor Display Buffer The display buffer which resides in addressable memory at B8000H incorporates 16 kilobytes of dynamic read write memory...

Page 97: ...ll provided hardware jumpers to enable either of the character types at powerup and or use 8088 I O OUT commands to program select your choice Timing Generator The timing generator creates the timing...

Page 98: ...characters Both uppercase and lowercase characters are available in all modes On a monochrome monitor reverse video blinking sixteen foreground and back ground levels of gray and highlighting features...

Page 99: ...ng address character byte must be an even numbered location Table 7 2 Monochrome Character Attribute Selection ATrRIBUTE BYTE BITS 7 6 5 4 3 2 I 0 FUNCTION B 0 0 0 I I I I B I I I I 0 0 0 B 0 0 0 I 0...

Page 100: ...required to store one screen This means only four screens may be stored at one time Graphics Mode In graphics mode two degrees of resolution are available 320 x 200 and 640 x 200 640 x 200 resolution...

Page 101: ...0 to B9F3F contain information for pixels in even numbered rows 0 through 198 Addresses BA000 to BBF3F contain information for odd numbered rows 1 through 199 Memory Address 68000 even scans 0 2 4 198...

Page 102: ...color Pixel becomes color I of current palette Pixel becomes color 2 of current palette Pixel becomes color 3 of current palette Table 7 5 Palette Structure C OLOR SET I I Cyan Magenta 3 White SET 2...

Page 103: ...mat because of memory limitations Addressing and mapping is the same as medium 320 x 200 resolution but formatting of the data is different In this submode each bit as opposed to a bit pair represents...

Page 104: ...the graphics pixels In high resolution 640 x 200 graphics mode it contains the ON or OFF status of the pixels The buffer address starts at BSOOOH CRT ControllerSignals The following paragraphs define...

Page 105: ...write information to one of the 6845 internal registers 6845 register select signal Rather than sacrifice five of the 40 available pins to 6845 register addressing one of the registers is used as an a...

Page 106: ...control signals Derived from the system dock to become the character rate dock in textmode Primary timing unit to the 6845 Initializes the 6845 When this pin goes low the internal counters are deared...

Page 107: ...EN is low during horizontal and vertical retrace and could also be called the video blanking signal CURSOR is the cursor enable signal which allows a steady stream of dots to be produced on the CRTscr...

Page 108: ...following sequence when selecting operating parameters for the video interface Determine desired mode of operation text mode or pixel addressable graphics 2 R eset video enable bit Also reset video ov...

Page 109: ...Page 7 20 Video Graphics Programming 5 8 x o Z aO o X l D ccI CJ cCI ccrc ccI ccI 4 8 0 C Q 0 0 0 N ccc X ccc 0 N 0 O O M 8 g 5 0N M X M 0 I Zl col...

Page 110: ...Page 7 21 Video Graphics Programming...

Page 111: ...page 7 22 Video Graphics Programming...

Page 112: ...ishes the cursor symbol position on the screen R16 and R17areonly used if a light pen is interhced Horizontal Timing and Format Registers The contents of register RO determines the total time allotted...

Page 113: ...point at which display enable DISPEN will be reset for vertical retrace R7 the verlical sync VSYNC position register determines the point at which the VSYNC signal makes its negative to positive trans...

Page 114: ...he top left corner to be displayed At the end of each vertical retrace the first screen memory address generated will be the one contained in these registers Since the 6845 addresses memory serially r...

Page 115: ...cter generator logic These outputs may represent scan line counts of from 0 to 31 or up to 32 scan lines per character row Register R9 the scan lines row register determines the maximum count from the...

Page 116: ...A8 A7 A6 A5 A4 A3 A2 AI AO 3DO I 3DI I 3D8 I 3D9 I 3DA I 3DB I 3DC I X Don t care I I I 0 I 0 X I I I 0 I 0 X I I I 0 I I 0 I I I 0 I I 0 I I I 0 I I 0 I I I 0 I I 0 I I I 0 I I I X 0 X I 0 0 0 1 I 0...

Page 117: ...200 graphics color palette selection color 0 Bits 6 and 7 are not used In text mode bits 0 I 2 and 3 determine the screen border color In 320 x 200 graphics submode these bits select the screen backgr...

Page 118: ...elects 80 x 25 text submode A logical 0 selects 40 x 25 submode A logical I selects 320 x 200 graphics submode A logical 0 selects text mode A logical 1 selects monochrome submode A logical 0 selects...

Page 119: ...Reserved for video diagnostics Used to light the LED located on the video card A logical 1 disables the color video interface and connects video output from an alternate video card located within you...

Page 120: ...1 1 0 1 1 1 1 0 1 1 1 1 0 1 0 0 0 1 0 0 1 1 0 1 1 FONT Power up double dot Single dot Underlined double dot Underlined single dot Power up single dot Double dot Underlined single dot Underlined doubl...

Page 121: ...during screen refresh intervals Logical I indicates that a positive going light pen signal has set the light pen trigger This trigger is reset at powerup and may also be deared by issuing an I O OUT c...

Page 122: ...parameters for a desired function are first placed in the appropriate registers and the function code for that operation is placed in the AH register Then the INT instruction for the video I O interr...

Page 123: ...BH AL Set screen mode Set cursor type Set cursor position Read cursor position Read light pen position Select active display page Scroll an area of screen up Scroll an area of screen down Read cursor...

Page 124: ...resolution monochrome at the RGB output 40 x 25 text emulation 640 x 200 pixel resolution monochrome at the RGB output All three scrolling modes available see scrolling selection 80 x 25 text display...

Page 125: ...used for storage of video pages in excess of the current page In video modes 0 and I the valid page numbers are 0 to 7 in modes 2 and 3 allowable values are 0 to 3 In the graphics modes only page 0 is...

Page 126: ...output a desired character and attribute to the current cursor position Load BH with the desired page number CX with a value represent ing the number of times to repeat the character AL with the chara...

Page 127: ...on Code 13 Read Graphics Pixel This operation returns the color of a pixel in a given location by returning the color value in AL Before calling load DX with the vertical position value and CX with th...

Page 128: ...ve video page Function Code 10 e l ect Scrolling Mode This routine allows you to select one of the three available scrolling modes Load AL with aval ue bet ween 0 and 2 If AL is 0 software scrolling i...

Page 129: ...f Figure 7 7 COLUMN YALUE 7 6 5 4 3 2 1 0 12864 3 2 16 8 4 2 1 X O 40 OK 3 2 BYTE 1 19 6 10 C4 BYTE 2 3 8 1 p 26 1 6 BYTE 3 2 5 1 0 1916 BYTE 4 5 7 1 0 3 9 16 BYTE 5 1410 E 16 BYTE 6 1010 A 1 6 BYTE 7...

Page 130: ...have a hexadecimal code of 80 and the last a code of FF All that remains now is to reset the pointer at interrupt vector 1F to the start of the memory section where your characters reside From now on...

Page 131: ...or the proper operation of your system Corresponding jumper numbers on the present video card do not correspond and perform the same functions on the early design video card Character Font Selection R...

Page 132: ...n J303 to V Position J305 to the video card markings corresponding to the vertical sync polarity required by your monochrome monitor positive or negative Position J306 to the markings corresponding to...

Page 133: ......

Page 134: ...rinter is by means of the routines provided in the monitor ROM built into the machine However certain applications may be more efficiently handled by using the infor mation provided here in conjunctio...

Page 135: ...n may result when using more than one of these devices at the same time For instance IR7 is the interrupt assigned to the parallel device port but may also be selected for COM2 if the jumper is placed...

Page 136: ...is the table vectored to when a device is configured using the MS DOS CONFIGURprogram but the parameters contained in this area of memory may also be changed by the user to suit his own unique device...

Page 137: ...case Pad character af t ercarr i age r etu rn Number of pad characters to issue ROM data segment time out value for a parallel device Serial Format The format for the two serial maps is shown in Table...

Page 138: ...handshake If bit I is logic 0 bit 3 is polarity of DTR if DTR active If bit I is logic I bit 3 is logic 1 if waiting for handshake character logic 0 if not If bit I is 0 bit 4 is logic I if RTS handsh...

Page 139: ...erial and Parallel Input Output Table 8 6 further defines byte 7 Table 8 6 Serial Byte 7 Breakdown BIT PARAMETER DESCRIPTION Word size Number of stop bits Define parity yes no odd even 0 I 2 3 4 5 6 7...

Page 140: ...l code followed by an INT 17H instruction Table 8 7 Parallel Device Operation Codes OPERATION CODE DESCRIPTION OF ACTION Print the next character in AL If the parallel device does not return a READY s...

Page 141: ...ceive character in AL from serial port Read communications status The following paragraphs further define these serial device operations 0 Function Code 0 Initialize the Serial I O Port The mode of th...

Page 142: ...00 4800 9600 Upon return from the initialization function the status of the serial port will be in AX AH will contain the line control status and AL the modem control status See Function Code 3 ReadCo...

Page 143: ...erface status the condition of which is returned as a bit mapped value in AX AH contains the line control status and AL the modem control status as shown by Tables 8 13 and 8 14 Table 8 13 Line Contro...

Page 144: ...8 14 Modem Control Status Register AL BIT STATUS CTS line has changed state DSR status haschanged End of ringing pulse detector Carrier Detect CD signal has changed state Status of CTS line Status of...

Page 145: ......

Page 146: ...on on the Central Processing Unit for the correct DIP switch settings for the desired system configuration including the selection of the auto boot drives present and number of drives option Use the a...

Page 147: ...troller If you have a Winchester hard disk drive installed refer to Figure 9 1 for the location of the two jumpers resident on the Winchester drive controller card Figure 9 1 Winchester Controller Con...

Page 148: ...der Selection Sl SWITCH SECTION DRIVE I DRI VE 2 I 2 3 4 HEADS CYLIND ERS 0 0 0 0 6 306 0 I 0 I 4 480 I 0 I 0 2 612 I I I I 4 306 The last option is standard factory configuration Q Boppy Disk Drive C...

Page 149: ...FLAT CABLE CONNECTOR STRIP TERMINATOR JUMPERS POWER CONNECTOR PROGRAMMING JUMPERS Figure 9 2 Mitsubishi Floppy Disk Drive Configuration Table 9 2 Mitsubishi Floppy Disk Drive Configuration JUMPER POS...

Page 150: ...pt for the last drive on the cable JUMPER CONFIGURATION DRIVE A o DRIVE 8 1 MX DS MX DS 4 3 2 1 DRIVE G 2 MX 4 3 2 0 1 DS MX 4 3 2 1 4 3 2 1 DRIVE D 3 DS JUMPERS PROGRAMMING TERMINATOR El POWER CONNEC...

Page 151: ...ack Return current drive parameters Initialize drive type characteristics Read sectors including 4 ECCbytes at end of each sector Write sectors including ECC bytes Seek a desired track Reset Wincheste...

Page 152: ...ed off following disk VO Bytes per sector 00 128 01 256 10 512 11 1024 Last sector of track Gap length in bytes Data length 7 80H if 128 bytes per sector FFH if not Gap length when formatting Fill dat...

Page 153: ...r of sectors to be transferred Pointer to the disk buffer segment in ES Offset in BX not required for function code 4 AL ES BX FunctionCode 5 Format Track When formatting a floppy disk the buffer poin...

Page 154: ...1H should point to the new drive type parameter table organized as four sets for the four possible drive types of information This is formatted as follows Number of Tracks Word Number of Heads Byte St...

Page 155: ...ccess from other devices on the da DMA boundary error Hardware is incapable of transferring sector information across 64K bound aries Can be corrected by reducing sector count in AL or by changing buf...

Page 156: ...between 0 and 3 expressed in ASCII 30H to 33H with 0 representing the default partition The routine will attempt to read from track 0 sector I of the spedfied device and execute the code it finds If...

Page 157: ......

Page 158: ...aker 1 3 Autoboot 2 2 Floppy disk 4 6 Winchester 4 6 B Backplane board 1 2 Bad disk controller 2 4 Bit mapped video graphics 2 14 Boot 2 2 2 8 9 13 Default 2 8 Bus 3 3 see also Autoboot C CAPS LOCK Fe...

Page 159: ...ges 2 4 9 12 Port addresses 9 6 DISK READTEST 2 5 DISPEN 7 18 7 24 Display memory seeMemory DMA controller 3 3 DMA overrun error 2 4 DOS 2 7 Drive not ready 2 4 see also MS DOS E Examine memory see Me...

Page 160: ...es 5 2 5 3 KEYBOARDTEST 2 5 Keypadspecial keys 5 17 L Light pen 7 1 7 23 7 25 Line feed 7 38 LPSTB 7 18 see also Disk drives Winchester see also RAM ROM M Mass storage 1 3 Memory 1 2 Access 6 6 6 7 Ad...

Page 161: ...2 2 2 4 2 8 Exiting 2 7 Operation codes seeKeyboard Output to port 2 11 see also MS DOS P Parallel Disable interface 8 2 Port 1 3 Parameter mapping 8 3 Parity 8 4 8 6 8 8 Parity hardware failure 2 3...

Page 162: ...tion 2 15 Search memory 2 12 Sector not found 2 4 Seek failure 2 4 Serial port 1 3 COMI 8 2 COM2 8 2 Parity 8 5 8 6 Service 2 2 Set Video Scroll 2 14 Speaker seeAudio speaker Special function keys 5 1...

Page 163: ...Index 6 Index V Video Card 1 2 2 5 Enable bit 7 19 Mode selection 2 14 VSYNC 7 18 7 24 W Winchester drives 1 3 9 10 9 13 Winchester drive controller 9 2 Configuration 9 2...

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