[Coco] How to check the amount of memory installed?

Bruce W. Calkins brucewcalkins at charter.net
Sun Jul 16 19:05:44 EDT 2017


Plug in a disk controller and disk, boot OS-9.  If it boots you have 
64k, if not then there are issues and/or less than 64k.

Bruce W.



On 07/16/2017 06:14 PM, Arthur Flexser wrote:
> Michael, if the Basic program you found for testing for 64K does nothing
> but check some location around 65000 decimal, you should be aware that this
> is not a reliable test, and really checks only for the Radio Shack upgrade
> version.  This program appears in some RS tech manuals.
>
> Art
>
> On Sun, Jul 16, 2017 at 6:08 PM, Bruce W. Calkins <brucewcalkins at charter.net
>> wrote:
>> Sounds like the 64k mod then.  I not seen any ceramic 64k chips, yet, but
>> that is not conclusive.  A close paint match is Mercedes Grey from the
>> 1980s,  I'm not sure how easy that will be to find these days though.
>>
>> Bruce W.
>>
>>
>>
>> On 07/16/2017 03:37 PM, Michael E Kent wrote:
>>
>>> Thanks, 24864 comes back so it is at least 32K I guess. The wiring is to
>>> a socketed chip to the left of the ram, and I think one of the pins was
>>> bent up. I will pull the cover again.  I will do some more testing to
>>> confirm it is worth restoration, now to find a decent color match for the
>>> paint! I found a listing for a basic program to do it so I will see what
>>> happens there!
>>>
>>> Thanks
>>> -----Original Message-----
>>> From: Bruce W. Calkins [mailto:brucewcalkins at charter.net]
>>> Sent: Sunday, July 16, 2017 12:03 PM
>>> To: Michael Kent
>>> Subject: Re: [Coco] How to check the amount of memory installed?
>>>
>>> PRINT MEM <ENTER>; Should give numbers in the 22-28k range for 32k,
>>> 12-14k for 16k and 2k for 4k installed memory.  If one of the chips
>>> involved in the extra wiring is the 74LS02 to the left of the RAM chips
>>> there might be 64k, but I have not seen ceramic 64k chips.  There is a
>>> program for checking for 64k, but I would have to search on line for it and
>>> don't have the time to look now.
>>>
>>> Bruce W.
>>>
>>>
>>>
>>> On 07/16/2017 10:27 AM, Michael Kent wrote:
>>>
>>>> I have a CoCo 1 it was originally a 4k machine, it has been modified but
>>>> all memory chips are ceramic type chips with no markings whatsoever(not
>>>> even on the bottom) alot of soldered wire jumpers and such are in the
>>>> vicinity of the ram. I am certain the ram is upgraded. There were also mods
>>>> to the case, including a cutout for a db25 connector (whatever was there is
>>>> gone) and sloppy repairs to the keyboard cable. I would like to restore
>>>> this one as It will give me a 1, 1b,2 and 3. I would like to confirm it is
>>>> functional before I do a restoration. It does turn on and the keyboard
>>>> works (it was disconnected when it arrived) basically got it for free with
>>>> a purchase of 2 disk controllers, which both work.
>>>> MikeRadio Shack alumnus 1983-1988
>>>>
>>>> Sent from Yahoo Mail on Android
>>>>
>>>>
>> --
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>>



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