User's Manual

PMAC User Manual
Writing a Host Communications Program 269
Write to base + $121
(if using DPRAM)
Write $00 into
maibox reg #1
Send command line to PMAC
(up to 16 characters)
Wait for interrupt
Read $A0 interrupt vector
and acknowledge interrupt
Power up or
reset PMAC
Send
a line to
PMAC?
All
characters
sent?
NO
YES
YES
NO
Read $A1 interrupt vector
and acknowledge interrupt
Write $00 into
maibox reg #1
Has an
interrupt
ocurred?
YES
NO
Read mailbox regs until:
1) <CR> encountered
2) <ACK> encountered
3) <BELL> encountered
4) All 16 regs have been read
Figure 56 PMAC VME Communications Flow Diagram
PMAC VME Interrupt Vector Assignments
PMAC VME Card Number Interrupt Vector Pair
0
$A0,$A1
1
$A2,$A3
2
$A4,$A5
3
$A6,$A7
4
$A8,$A9
5
$AA,$AB
6
$AC,$AD
7
$AE,$AF