11 Oct
2014
11 Oct
'14
midnight
On Fri, 10 Oct 2014, Engel, Michael wrote:
After carefully examining the power supply and
checking the generated
voltages, we were convinced that this wouldn't kill our Multibus boards.
Maybe some of you are interested in our progress, so I though I would
send you an update.
Yes please! I long for the days when it was possible to understand the
entire kernel source...
After reconnecting the Multibus backplane, we started
the system with
only a CPU board and a memory board. On one of our CPU boards the
smaller (P2) Multibus connector is masked with tape, I'll have to dig
deeper to find out what is deactivated by this…
The P2 bus is designated as "private" i.e. do whatever you want with it
with your proprietary hardware. I don't think the "standard" CPU board
even looks at it.
One of our two CPU boards is currently non functional
(the one without
the masking take, this doesn't say a thing on the console UART, will
bring in the scope in Monday to check for details). The other one brings
up the monitor startup message and prompt on a connected serial terminal
(emulator) - however, we are unable to get any characters echoed back.
The serial cable is working, we tried all sorts of handshake
configurations. If we get any characters back (the system is running at
9600 baud, I tried all combinations of 7/8 bit, none/even/odd/mark/space
parity and 1/2 stop bits), these are garbled and contain mostly "1" bits
(0xfc, 0xfe, 0xff or similar).
Have you tried speeds other than 9600? They look to me like framing
errors.
-- Dave