0
\$\begingroup\$

I have a board on which core for VME64 bus is implemented and it communicates with other boards on VME64 bus using only 1 connector (P1, 5 rows, 32 pins on each row, total 160 pins) instead of 2 connectors (P1 and P2). I am trying to understand its working in both Bus controller and Remote terminal modes.

I have to modify the connector pinouts to make room for free pins on the P1, 160-pins connector. There is lot of info available about the bus but what I could not find out is the minimum pins required to use VME64 bus?

I can live with only 24-address lines on the bus. But I don't know which other lines I can compromise on to make room for free pins on the P1 connector?

VME64 Connector VME64 Signal names

\$\endgroup\$
1
\$\begingroup\$

I don't know what else is in the system and using the bus, but I would look at the bus arbitration lines: e.g. BR3, BG3IN, BG3OUT.

If there are not other bus masters (Processors or DMA controllers) they should be unused.

\$\endgroup\$
  • \$\begingroup\$ Will it be compatible to VME64 bus if we only use 24-address lines which are on the P1 connector? \$\endgroup\$ – alt-rose Jul 26 at 6:02
  • 1
    \$\begingroup\$ Depends on what else is plugged into the back-plane. If some card in the system uses the top address bits for decoding, you have a problem. \$\endgroup\$ – Oldfart Jul 26 at 15:03

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.