Xycom XVME 200 Manual page 33

XVME-200/290 Manual
December, 1987
1
7 6
PC7/TIACK PC6/PIACK
Input
Input
Figure 3-3. Port C/Alternate Function Signal Definitions
The following is a brief explanation of each PORT C bit:
0 and 1 are used to control the direction of the 8-bit
Bits
transceivers which are used to buffer the Port A and Port B data
lines.
outputs.
2 is used as a timer input line if the 68230 timer function is being
Bit
utilized.
employed as a general purpose input line.
.
3 is used as a timer output line if the 68230 timer function is being
Bit
utilized.
employed as a general purpose output line.
l
4 is used as a timer interrupt enable line of the 68230 timer
Bit
function is being utilized. This bit can only be used for the timer
interrupt function.
.
5 is used as a port interrupt request line if the 68230 port
Bit
interrupts are enabled. This bit can only be used for the port
interrupt function.
l 6 is used as a port interrupt acknowledge line if the 68230 port
Bit
interrupts are enabled.
interrupt function.
.
7 is used as a timer interrupt acknowledge line if the 68230 timer
Bit
functions are being utilized.
timer interrupt function.
5 4
PIRQ TINTEN
output output
After start-up or reset, these bits should be programmed as
If the timer function is not being used, this bit could be
If the timer function is not being used, this bit could be
3-6
3 2
PC3/TOUT PCZ/TIN
output Input
This bit can onlv be used for the port
This bit can only be used for the
1
1 0
PORT B PORT A
output output
data