IMS 5000 Series Manual page 75

bit 5
bit 6
bit 7
bit 4 = 1 Floppy disk controller is busy processing a read or
write command
Set during the execution phase of non DMA operation only
Set
if
data transfer is to be from data register to processor
Set if data register is ready to send or receive data to or
from processor
IN CFH - Read disk data from data register in 765 Floppy Controller Chip.
OUT CFH - Write data for disk ir.to data register on 765 Floppy Controller Chip.
CONNECTIONS
The
J1
connector on the
431
board is connected to the floppy disk drive
~ith
a
ribbon cable.
If
there is more than one drive, this cable is daisy-chained to the
other drive(s). The pin assignments for the ribbon cable are Shugart compatible.
They are listed below. The pin numbers are the same for the board and the drive
because a flat ribbon cable is used.
Signal
z
..
6
•
10
12
14
16
18
Z1)
ZZ
Z4
26
28
30
32
34
36
38
40
42
44
46
48
50
ALL ODD
SPARE
IN USE
SEL
4
INDX
SEL 1
SEL
2
SEL 3
MON
IN
STP
WDAT
WGAT
TRACKO
WPROT
RDATA
SDEI
SEPDAT
GROUND
IMS International
5000 Series Microcomputers/7.0 1.83;Page 73