82C55A
INTERRUPT
REQUEST
INTERRUPT
REQUEST
PC3 PA0
PA1
PC3 PA0
PA1
D0
D1
D2
D3
D4
D5
D6
D7
R0
R1
R2
R3
R4
R5
R6
R7
PA2
PA3
PA4
PA5
PA2
PA3
PA4
FLOPPY DISK
CONTROLLER
AND DRIVE
B LEVEL
PAPER
TAPE
READER
PA5
PA6
PA7
MODE 1
(INPUT)
MODE 2
PA6
PA7
PC4
PC5
PC7
PC6
PC4
PC5
PC6
DATA STB
ACK (IN)
DATA READY
STB
ACK
STOP/GO
ACK (OUT)
MACHINE TOOL
82C55A
82C55A
PC2
PC1
PC0
TRACK “0” SENSOR
SYNC READY
INDEX
PC0
PC1
PC2
START/STOP
LIMIT SENSOR (H/V)
OUT OF FLUID
MODE 0
(INPUT)
PB0
PB1
PB2
PB3
PB4
PB5
PB6
PB7
ENGAGE HEAD
FORWARD/REV.
READ ENABLE
WRITE ENABLE
DISC SELECT
ENABLE CRC
TEST
PB0
PB1
PB2
PB3
PB4
PB5
PB6
PB7
CHANGE TOOL
LEFT/RIGHT
UP/DOWN
HOR. STEP STROBE
VERT. STEP STROBE
SLEW/STEP
MODE 0
(OUTPUT)
MODE 0
(OUTPUT)
FLUID ENABLE
EMERGENCY STOP
BUSY LT
FIGURE 23. BASIC FLOPPY DISC INTERFACE
FIGURE 24. MACHINE TOOL CONTROLLER INTERFACE
16
HARRIS [ HARRIS CORPORATION ]
