Re: Pinouts for the P4 connector in 3/80, maybe others?

[Izumi Tsutsui <tsutsui%ceres.dti.ne.jp@localhost>]

> TL;DR: looking for pinouts of the P4 connector in 3/80, possibly other
> sun3x (3400 CPU board) and early sun 4 (4300 CPU board)
 :
> I'm looking for the pinouts of the P4 connector in the 3/80, which is
> documented as different from the one in the 3/60 and 4/ systems.
> Physically it's easy, it's a 3x32 pins DIN 41612 connector, extremely common.

The only info about P4 I know is "THE SUN HARDWARE REFERENCE" part 1:
 http://www.sunhelp.org/faq/sunref1.html

It just says

>>    3/60
>>        Processor(s):   68020 @ 20MHz, 68881 (stock), Sun-3 MMU,
>>                        8 hardware contexts, 3 MIPS
>>        CPU:            501-1205/1322/1334/1345
>>        Chassis type:   wide pizza box
>>        Bus:            P4 connector (not same as P4 on 3/80)

>>    3/80
>>        Processor(s):   68030 @ 20MHz, 68882 @ 20MHz, 68030 on-chip
>>                        MMU, 3 MIPS, 0.16 MFLOPS
>>        CPU:            501-1401/1650
>>        Chassis type:   square pizza box
>>        Bus:            P4 connector (not same as P4 on 3/60)

On the other hand, several Sun handbook pages say certain
P4 framebuffers are common among 3/60, 3/80, and even 4/110 etc:
 https://dogemicrosystems.ca/pub/Sun/System_Handbook/Sun_syshbk_V4.1/Systems/Sun3/Video_Graphic_TOC.html

MG3:
 https://dogemicrosystems.ca/pub/Sun/System_Handbook/Sun_syshbk_V4.1/Systems/Sun3/VIDGRA_13_MG3.html

CG4:
 https://dogemicrosystems.ca/pub/Sun/System_Handbook/Sun_syshbk_V4.1/Systems/Sun3/VIDGRA_17_CG4.html
 though my 501-1443 on 3/80 doesn't have BNCs:
 https://twitter.com/tsutsuii/status/1295717070093594624
 (I also have 501-1210 for 3/60 but have not tested yet)

CG6:
 https://dogemicrosystems.ca/pub/Sun/System_Handbook/Sun_syshbk_V4.1/Systems/Sun3/VIDGRA_18_CG6.html

MG4 is not for 3/60, but due to physical shape?
 https://dogemicrosystems.ca/pub/Sun/System_Handbook/Sun_syshbk_V4.1/Systems/Sun3/VIDGRA_14_MG4.html

> And also, how does (if it does) the system detect the framebuffer on
> said P4 device (SBus is easy with OpenBoot/OPenFirmware, not sure what
> the 3/80 does, haven't tried booting mine n 20 years and the PSU seems
> long dead, idly wondering how to resurrect it with a modern display).

As Jeremy noted, P4 looks a dumb bus (like ISA) and it doesn't provide
functionalities for device detection. Each driver should actually "probe"
if the target device is the expected address space.

It looks newer cgfour for Sun4 machines have "P4 ID"
 https://github.com/NetBSD/src/blob/728cf8e9/sys/arch/sparc/dev/cgfour.c#L202-L207
but I have not checked it on my 501-1443 on 3/80.

---
Izumi Tsutsui