Hi all,

Railsrust had posted regarding interfacing a W65c134 with a W65c265 via its Parallel Interface Bus or PIB. I thought that this would fall under the Hardware topic so I put it here.

I think it would be doable using the '134's PCS30 chip select and the address lines 0, 1 and 2 to the PIB's
PIRS0, PIRS1 and PIRS2 as well as the '134's R/WB to the PIB's PIWEB.

While the question of how to connect the 2 MCUs together via the PIB why would someone want to do that?
I came up with at least 2 answers:

The '134 has 2 IRQB level interrupts and more additional edge interrupts than the '265 so the '134 could handle those interrupt sources and pass their address to the '265 to process.

Likewise, the '265 operates in native 8/16 bit mode so if faster more dense code need be processed for the '134 the PIB would be a gateway for that to take place.

While the W65c134's SIB is strictly for connecting up to 8 W65c134s together via SIB I think the PIB is a bit more flexible. I can at least imagine a W65c265's PIB interfaced to an Apple II expansion slot and handling 2 UARTs with buffering for an Apple IIe or IIgs at up to 115kb or more.

If I come up with any hardware to demonstrate the use of the PIB I will put it here.

(some minor editing)

Cheers,
Andy