Re: 10.0_RC5 at boot on VAX 4000/200

[Johnny Billquist <bqt%softjar.se@localhost>]

On 2024-04-16 21:36, George Harvey wrote:
> I had started sprinkling printfs through the code but other calls on my time came along before I reached any conclusion. The stage I had got to was different results coming back from the CMD controller when polled in mscp_waitstep() in dev/mscp/mscp_subr.c.
>
> Netbooting I saw:
>
> [   1.0000000] ubasearch: calling config_probe
> [   1.0000000] udamatch: tries=0, mi_iot=80335a78, mi_iph=8afeb468
> [   1.0000000] udamatch: mscp_waitstep 1
> [   1.0000000] mscp_waitstep: read_val=00000800, result=00000800, status=1
>
> Booting from disk I saw:
>
> [   1.0000000] ubasearch: calling config_probe
> [   1.0000000] udamatch: tries=0, mi_iot=80335a78, mi_iph=8afeb468
> [   1.0000000] udamatch: mscp_waitstep 1
> [   1.0000000] mscp_waitstep: read_val=00000000, result=00000800, status=0
>
> The all-zeros read value leads to the board not being recognised but I've got no idea why that only happens with disk boot.

Hum. This reminds me a bit of a bug in 2.11BSD where the code worked on 
a real DEC controller, but failed on a CMD controller in the 
initialization step.

I need to go back and read up on what that issue was. I fixed it in some 
place in the code about 20 years ago...

Might be a similar issue...

  Johnny

--
Johnny Billquist                  || "I'm on a bus
                                  ||  on a psychedelic trip
email: bqt%softjar.se@localhost             ||  Reading murder books
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