> On Jan 27, 2018, at 11:16 AM, Mark Matlock via cctech <[email protected]> > wrote: > > I have an ADV11-A that I would like to use in a Q22 RSX11M+ system. The > ADV11-C will work in a 22-bit Bus system from what I understand but the > ADV11-A was made for 18 bit Bus systems. In the OEM Micronote book, Note 5, > it states: > > Any device which uses backplane pins BC1, BD1, BEl, BF1 or DC1, 001, DEl, > OF!, for purposes other than BDAL18-21 is electrically incompatible with the > 22-bit bus and may not be used without modification. > > > Further down it lists the ADV11-A as a device that does not meet the > requirements for a Qbus 22-bit system because: > ADV11 (A012). A/D Converter. (Use of BC1 for purposes other than > BDAL18) > > When I look at the Board connector B pin C side 1 (component side) the BC1 > pin is tied to ground. Several other pins are also tied to ground on that > connector such as BC2, BJ1, and BT1. Other than BC1 which is BDAL18 being > tied to ground the pins BDAL19 (BD1), BDAL20 (BE1), And BDAL21 (BF1) are all > not connected to anything. This also matches the field engineering print for > ADV11-A (B-TC-ADBV11-A-1) where BC1 is shown tied to ground on page 21. > > So it looks like if I simply cut the trace between the BC1 finger and its > connection to ground on the board it would become Q22 compatible. > > Is it that simple? >
I am considering the same modification to my own ADV11-A. I just located the field maintenance print you referenced, so I can now research this a bit further myself. Being a interrupt only device and using on BBS7 to decode the IO page, this should function in an Q/Q backplane slot "in theory". Jerry [email protected]
