Re: My //e died. Can you help me fix it?

[nathan@visi.com (Nathan Mates)]

In article <drew-1309961721100001@dewey.ctnet.com>,
Drew Ivan <drew@ctnet.com> wrote:
>drew@ctnet.com (Drew Ivan) [that's me] wrote:
>>I recently brought my //e out of mothballs just for fun. Despite
>>years of disuse, it booted up and worked fine for a week or more.
>>I wrote a little AppleSoft BASIC program to compute some fractal 
>>functions and left it running at work over the weekend. When I 
>>came in on Monday morning, it had blinking characters on the text
>>screen, and it wouldn't respond to any commands. 

>I don't know why, but when I did the self test for the nth 
>time, it gave me a message: "MMU Flag E4:7". Is this likely
>to be the extent of my problem? How'd it get broke? How can
>I fix it?

   On my enhanced //e, the MMU ("Memory Management Unit", though that
has nothing to do with memory protection and other features that other
processor's MMUs provide) was a socketed chip close to the
processor. (Read the white printing on the motherboard) Check to see
if it or other chips are partway out of the sockets-- give them a firm
press down with your thumb. There'll likely be a little creaking as
they're installed; don't push too hard and break the motherboard
(tough to do)

   If it's not a socketing problem, the chip may just need
replacement. Alltech Electronics, Shreve Systems, or Sun Remarketing
may have such chips, or they'll sell/swap you a motherboard.

Nathan Mates

--
<*> Nathan Mates http://www.visi.com/~nathan/      <*>
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