DIGITAL-LOGIC MICROSPACE MSM800SEV, Техническое руководство пользователя

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DIGITAL-LOGIC AG
MSM800 SEV Manual V1.0A
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4.4.4 Floppy Disk Interface
The onboard floppy disk controller and ROM-BIOS support one or two floppy disk drives in any of the stan-
dard PC-DOS and MS-DOS formats shown in the table .
Supported Floppy Formats
Capacity Drive size Tracks Data rate DOS version
1.2 MB 5-1/4" 80 500 KHz 3.0 - 6.22
720 K 3-1/2" 80 250 KHz 3.2 - 6.22
1.44 M 3-1/2" 80 500 KHz 3.3 - 6.22
Floppy Interface Configuration
The desired configuration of floppy drives (number and type) must be properly initialized in the board's
CMOS - configuration memory. This is generally done by using DEL or F2 at bootup time.
Floppy Interface connector
The table shows the pinout and signal definitions of the board's floppy disk interface connector. It is identical
in pinout to the floppy connector of a standard AT. Note that, as in a standard PC or AT, both floppy drives
are jumpered to the same drive select: as the 'second' drive. The drives are uniquely selected as a result of a
swapping of a group of seven wires (conductors 10-16) that must be in the cable between the two drives.
The seven-wire swap goes between the computer board and drive 'A'; the wires to drive 'B' are unswapped
(or swapped a second time). The 26 pin high density (1mm pitch FCC) connector has only one drive and
motor select. The onboard jumper defines the drive A: or B:. Default is always A:.
Floppy Disk Interface Technology
We only support CMOS drives. That means that the termination resistors are 1 Kohm. 5 1/4“-drives are not
recommended (TTL interface).
The 26 pin Connector: FFC/FPC 0.3mm thick 1.0mm (0.039") pitch (MOLEX 52030 Serie)
Floppy Disk Interface Connector
FD26: Pin Signal Name Function in/out
1 VCC +5 volts
2 IDX Index Pulse in
3 VCC +5 volts
4 DS2 Drive Select 2 out
5 VCC +5 volts
6 DCHG Disk Change in
10 M02 Motor On 2 out
12 DIRC Direction Select out
14 STEP Step out
16 WD Write Data out
17 GND Signal grounds
18 WE Write Enable out
19 GND Signal grounds
20 TRKO Track 0 in
21 GND Signal grounds
22 WP Write Protect in
23 GND Signal grounds
24 RDD Read Data in
25 GND Signal grounds
26 HS Head Select out
4.4.5 Speaker Interface
One of the board's CPU device provides the logic for a PC compatible speaker port. The speaker logic signal
is buffered by a transistor amplifier, and provides approximately 0.1 watt of audio power to an external 8 ohm
speaker. Connect the speaker between VCC and speaker output to have no quiescient current.