.
Just my guess.
Dwight
From: Cameron Kaiser via cctalk
Sent: Friday, May 12, 2023 8:51 AM
To: Jon Elson via cctalk
Cc: Cameron Kaiser
Subject: [cctalk] Re: KIM-1 stuck bits from $280 to $29f
> If the failure affects the EPROM monitor,then any results you get f
> If the failure affects the EPROM monitor,then any results you get from the
> monitor are suspect.
No, what I mean is, the appearance of the upper six bits being dead was because
of how the monitor shifts in data from the keypad. Since bit 2 was always zero,
it would look like everything above it
On 5/11/23 21:41, Cameron Kaiser via cctalk wrote:
I thought about this, but the KIM is a pretty simple system. The only memory
mapped device in that range (really, on the entire unit) are the RIOTs, and
their RAM at $1780 is fine and does not echo.
The KIM only does address decoding for 8K and
Thanks for the suggestions, everyone. This board has NEC D2102AL-4 SRAMs on it,
so I ordered a couple MM2102AN-4s which look equivalent. I'll swap one in when
it arrives and see if that's the problem.
--
personal: http://www.cameronkaiser.com/ --
Cameron Kai
> On May 11, 2023, at 10:41 PM, Cameron Kaiser via cctalk
> wrote:
>
>> I thought about this, but the KIM is a pretty simple system. The only memory
>> mapped device in that range (really, on the entire unit) are the RIOTs, and
>> their RAM at $1780 is fine and does not echo.
>>
>> The KIM o
On 2023-May-11, at 7:41 PM, Cameron Kaiser via cctalk wrote:
> it's actually an artifact of the monitor that the upper 6 were clear.
> Actually,
> the stuck bit is entirely bit 2 (i.e., it goes
>
> 0 1 2 3 4 5 6 7 8 9 a b c d e f
> 0 1 2 3 0 1 2 3 8 9 a b 8 9 a b
>
> and the high nybble is OK).
> I thought about this, but the KIM is a pretty simple system. The only memory
> mapped device in that range (really, on the entire unit) are the RIOTs, and
> their RAM at $1780 is fine and does not echo.
>
> The KIM only does address decoding for 8K and echoes the rest, so the same
> fault is map
>> Odd fault on my Rev D KIM-1 popped up while writing code this afternoon
>> (initially I thought I had a bug in my paper tape transmitter) - between
>> $0280
>> and $029f, the upper 5 bits are stuck at zero. The rest of the address range
>> seems fine. In particular, $0080-$009f, $0180-$019f and
On 5/11/23 00:53, Cameron Kaiser via cctalk wrote:
Odd fault on my Rev D KIM-1 popped up while writing code this afternoon
(initially I thought I had a bug in my paper tape transmitter) - between $0280
and $029f, the upper 5 bits are stuck at zero. The rest of the address range
seems fine. In par
