Hi Peter, > However, they do not provide the SROM> prompt or accept mini console commands > unless a I engineer another fault condition such as by pulling out one of the > memory risers. I wonder if there is a jumper to enable mini console commands > to be accepted without doing this? Looking around the system board, I see a > pair of jumper pins labelled J9 hidden under the I/O board which looks like it > could do this. Unfortunately, while there is legend on the PCB indicating the > function of all other jumpers, there is none for J9 and it is not mentioned in > the manual either.
"DEC 3000 Models 600/600S AXP and 800/800S AXP Service Information", Order Number: EK-FLSPC-SV. A01 (flspcsva.pdf) seems to indicate on page 2-2 that the SROM console jumper is one in position 0 among the SROM jumpers whose location is shown in the figure on that page. I have checked my /700 (which is the same as the /600 except for a faster CPU) and this is also marked J8 on the PCB. > The 600 machines have a socketed 27C512 EPROM. I assume this must be the SROM > (although I can't see what is serial about it) as the machines fail to update > the diagnostic LEDs or write to the mini console if it is removed. I dumped > the two EPROMs and compared them and they are identical. However, I can't see > any ASCII strings in them. Perhaps the bits are not used in the standard > order? The manual suggests that there are 8 different 8KB SROM images present > and those other than the "standard" one may be used for testing and > diagnostics > by setting jumpers. Unfortunatly, there is no further information about these > images. The location of the SROM chip is also shown in the figure on page 2-2. > The format of the headers in the SYSROM and IOROM do not exactly match the > format given in the manual but they are "close". I wonder if this might > be my problem or if the manual is incorrect. If anyone else has a 3000 600, > could they take a peek at their SYSROM and maybe we could compare notes? I could check my /700 with SRM. What would you like me to look at? Hope this helps. Good luck with your fault debugging. Maciej