From mboxrd@z Thu Jan 1 00:00:00 1970 From: dave@horsfall.org (Dave Horsfall) Date: Sat, 11 Oct 2014 05:00:07 +1100 (EST) Subject: [TUHS] Codata restoration - day 1 In-Reply-To: References: Message-ID: 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