on 4/28/00 12:08 AM, Toru Nishimura at nisimura@itc.aist-nara.ac.jp wrote
something like:

>> Perhaps a special purpose register on
>> the I2C master (and in this case only) controller? That being the case,
>> could we not just read the values? I'm assuming the trick is knowing
>> if/where they are stored.
> 
> i2c detail is invisible.  Control/data protocol is defined by
> ACCESS.bus.  ULTRIX runs complicated work to send/receive ACCESS.bus
> packets back and forth with great efforts.
> 
> Tohru Nishimura

    Then how is the PROM exec able to talk with a.b. devices? Are the same
instructions that Ultrix uses embedded in the EEPROM? I find it hard to
believe that DEC would have gone through all the trouble of redesigning
devices, hardware, and OS all for i2c/a.b. if a.b. were so difficult and
troublesome to use. (Even they couldn't get it to work right all the time
under Ultrix 4.3)

    Chris

-- 

Murphy was an optimist.