EDMONDS@prlvax1.prl.philips.co.uk (Mark from Philips) (02/02/90)
Does anyone know of a mouse/transputer board out there? Or is it a simple case of buying an RS232 to transputer interface and plugging a mouse in? Has anyone done this? Thanks in advance, Mark Edmonds edmonds@uk.co.philips.prl
ccplumb@lion.waterloo.edu (Colin Plumb) (02/05/90)
In article <900202114455.000014B40C1@prlvax1.prl.philips.co.uk> EDMONDS@prlvax1.prl.philips.co.uk (Mark from Philips) writes: > Does anyone know of a mouse/transputer board out there? > Or is it a simple case of buying an RS232 to transputer interface and plugging > a mouse in? Has anyone done this? Assuming the mouse you want to use sends RS232 signals (like many IBM PC mice), then that's all there is... except for writing a device driver, of course. At Cogent, it was just a Z8530 serial chip (and that %^&%^ 2.2 us delay between accesses; almost worth a context switch, but not quite) hung off the bus with some apropriate chip select decoding circuitry. This is where I learned that transputers are really great I/O processors. Interrupt dispatching is a bit of a pain, but the on-chip timer makes real-time constraints easy to satisfy, and the unaligned block move is useful for buffer-bashing. I just wish there was an instruction to copy from a 1-byte-wide port to a 4-byte-wide one. The 2-D move could do the job, but the penalty per line is absolutely disgusting; it was faster to write our own. -- -Colin