User's Manual

PMAC User Manual
268 Writing a Host Communications Program
DP: (for 32-bit fixed point), and F: (32-bit floating point). For sending data back to the host, the PMAC
data gathering function can also be used, directed to the dual-ported RAM rather than the regular RAM
(I45 controls). See the PMAC DPRAM User manual (Option 2 manual) for details.
Using Multiple PMAC VME Cards on the VME bus
Install multiple PMAC VME cards on the VME bus. Up to 16 PMAC VME cards may be controlled by a
single host computer. Each card, or course, must have a unique base address and DPRAM starting
address (if installed) such that none of the cards overlaps each other (or any other device on the VME
bus) in memory. Also, set up each card to have unique interrupt levels with unique interrupt vector
numbers. Each PMAC VME card occupies 512 VME bus memory locations (not including the 8K of
memory space taken up by DPRAM). That is, if the first PMAC VME is base addressed at $7FA000, the
second PMAC card must be base addressed at $7FA200. If there are PMAC VME cards installed on the
VME bus, with the first card starting at $7FA000, the addresses of the mailbox registers (MB) of each
card could be set according to the following table.
Suggested Base Addresses For Multiple PMAC VMEs
Card 0 Card 1 Card 2 Card 3 Card 4 Card 5 Card 6 Card 7
Base
7FA000 7FA200 7FA400 7FA600 7FA800 7FAA00 7FAC00 7FAE00
MB #0
7FA001 7FA201 7FA401 7FA601 7FA801 7FAA01 7FAC01 7FAE01
MB #1
7FA003 7FA203 7FA403 7FA603 7FA803 7FAA03 7FAC03 7FAE03
MB #2
7FA005 7FA205 7FA405 7FA605 7FA805 7FAA05 7FAC05 7FAE05
MB #3
7FA007 7FA207 7FA407 7FA607 7FA807 7FAA07 7FAC07 7FAE07
MB #4
7FA009 7FA209 7FA409 7FA609 7FA809 7FAA09 7FAC09 7FAE09
MB #5
7FA00B 7FA20B 7FA40B 7FA60B 7FA80B 7FAA0B 7FAC0B 7FAE0B
MB #6
7FA00D 7FA20D 7FA40D 7FA60D 7FA80D 7FAA0D 7FAC0D 7FAE0D
MB #7
7FA00F 7FA20F 7FA40F 7FA60F 7FA80F 7FAA0F 7FAC0F 7FAE0F
MB #8
7FA011 7FA211 7FA411 7FA611 7FA811 7FAA11 7FAC11 7FAE11
MB #9
7FA013 7FA213 7FA413 7FA613 7FA813 7FAA13 7FAC13 7FAE13
MB #10
7FA015 7FA215 7FA415 7FA615 7FA815 7FAA15 7FAC15 7FAE15
MB #11
7FA017 7FA217 7FA417 7FA617 7FA817 7FAA17 7FAC17 7FAE17
MB #12
7FA019 7FA219 7FA419 7FA619 7FA819 7FAA19 7FAC19 7FAE19
MB #13
7FA01B 7FA21B 7FA41B 7FA61B 7FA81B 7FAA1B 7FAC1B 7FAE1B
MB #14
7FA01D 7FA21D 7FA41D 7FA61D 7FA81D 7FAA1D 7FAC1D 7FAE1D
MB #15
7FA01F 7FA21F 7FA41F 7FA61F 7FA81F 7FAA1F 7FAC1F 7FAE1F
In addition to having unique addresses, each PMAC VME must also have unique interrupt vector
assignments. However, all the PMACs may use the same interrupt level (interrupt level 2 in the previous
examples). The table below shows suggested interrupt vector assignments for each PMAC VME card.