Byte Swapping Capability
rev 2.0
SFPCI-VME SERIES User’s Guide and Installation Manual
43
The content for ID register should reflects the revision of SF_VME Adaptor board. If
this is a rev. F board, a read back from ID register will return 01000110, which is an “F”
in ASCII.
Application software can enable/disable byte swap logic “on-the-fly”. Once the byte
swap function is set up by executing a command, byte swapping function is ready.
There are three main commands for the byte swap functions:
. enable byte swap (byte, word, long word),
. reading the current byte swap status,
. reading the ID register for rev F (01000110 in binary).
Currently there are three modes of byte swapping supported: byte swap, word swap
(two bytes), and long word (4 bytes) swap. These byte swapping modes can be set up
with one command. There is also one single command to enable all three modes of byte
swapping. In that case byte swapping is automatic for byte, word, and long word.
FIGURE 14
Jumper setting for address 0xFF00
Jumper U44
Jumper U45
A12
A13
VCC
Address=FF00
4.7k Ohm
4.7k Ohm
10 Ohm
10 Ohm
