rfl@oddjob.UChicago.EDU (Bob Loewenstein) (08/04/88)
We are designing an interface between CCD camera electronics and the macII via NuBus. The CCD readout electronics requires that 1.5Mb of data be transferred in 2 byte segments, and each 2 bytes must be handled within 25 microseconds. All communication with CCD electronics is done over serial lines, and we have designed circuitry for parallel-serial and serial-parallel conversion. We need to know whether the macII mother board can be operated in a tight software loop, avoiding interrupts and locking the NuBus, so that it can slave our interface card in a slot and pick up two bytes of data every 25 microseconds. Alternatively, what is the feasability of designing an interface card that could become master and lock the bus to write directly to memory in the motherboard? We are also interested in knowing about any bare-bones, generic interface circuitry for the MacII - NuBus, including declaration ROM, slot decoding, and simple handling of NuBus transactions and arbitration signals. Any suggestions/help would be appreciated.
dwb@Apple.COM (David W. Berry) (08/05/88)
In article <14980@oddjob.UChicago.EDU> rfl@oddjob.UChicago.EDU
(Bob Loewenstein) wants information on NuBus and the Mac II.
I'd suggest you get a copy of _Designing Cards and Drivers for
Macintosh II and Macintosh SE_, Addison-Wesley, 1987. ISDN
0-201-19256-X. It should tell you more than you ever wanted to
know.