| Posted By
crock
on 2011-10-04
16:43:18
 |  Any other 232 owners?
Thanks to Pipzter, I am now the proud owner of an immaculate 232!! This being my first look at a 232, I was surprised at how complex the ram circuitry is (there's an extra 74ls74 and 74ls32 to handle a14 and CAS.)
Would love to hear from any other 232 owners I can compare notes with.
Rob
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Posted By
Luca
on 2011-10-05
03:59:58
 | Re: Any other 232 owners?
I've seen you posted some pictures on "another site", and I'm gonna pick a couple of them to place here at hardware's pages 
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Posted By
crock
on 2011-10-05
04:23:49
| Re: Any other 232 owners?
By all means, go ahead.
The quality of the PCB pics is not great, I took them on my mobile before I left for the airport this morning (i'm now sitting in the business lounge in Frankfurt) Unfortunately I'm not back at home until 17th October but I will post much better ones of it inside and out when I get back.
Also keen to hear if anyone has a lower SN than the +4!!
Rob
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Posted By
TLC
on 2011-10-05
04:28:33
| Re: Any other 232 owners?
Congrats!
Photos, and, if possible, a schematic diag, please!
Most of CBM related technical material has been gathered together in the funet cbm archive; a, say, impersonal, strictly technical place (originating from the age when www wasn't even around), which has been hosted in a virtually unchanged form by Bo Zimmerman at ftp/www.zimmers.net/anonftp/pub/cbm for the last couple of years. Someone has already uploaded, for example, V364 ROMs and other early 264 prototype related material, but there's certainly no info, let alone photos, ROM dumps, sch, etcetera, about the 232. It'd be nice to add what is currently at your hands, for everyone's benefit (IMHO).
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Posted By
crock
on 2011-10-05
06:10:15
| Re: Any other 232 owners?
I can tell you that the roms are the v1 versions of the basic and kernal rom found in the other 264 machines, burnt onto eproms.
I wish I did have schematics - not sure how I would go about reverse engineering them from the PCB. I am sure 90% of it is the same as the plus 4, the biggest difference is probably the lack of user port / rs232 port and the circuitry to handle 32k of ram, which seems quite different to the c16/+4.
Better photos will have to wait a while i'm afraid, but i promise I will do it.
[edit]
Realised I had a better photo of PCB on wife's camera. Managed to upload it onto my server at home from airport. My upstream bandwidth is not great but here is a better pic of the pcb.
http://clarke-family.org.uk/232PCB.JPG
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Posted By
TLC
on 2011-10-05
07:52:45
| Re: Any other 232 owners?
OH-MY-GOD! 
This is just awesome! I've always wondered how they managed to put "32k" of RAM into the machine. 32k ram is just "odd" and illogical. Even the most straight looking way (using "faulty" 64k ie. 4132 chips, like Sinclair had been doing) sounded illogical for 1984, with the drop of 64k*1bit chips prices. Now, your 232 motherboard seems to have 4 pieces of 16k*4 bit chips... Absolute surprise! I wouldn't have thought that they opted for that way... Now I can perfectly understand why they just "had to" modify the dram ttl logic of the 232...
Anyway, thank you for uploading the photo, it's a very nice board, basically no signs of age, fingerprints, etc. Probably the only ceramic packaged 6529B and 7700 FPLA t that I've ever seen. Obviously a very early 264 series machine. I'm just trying to hide my envy... (with less to no success... )
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Posted By
George
on 2011-10-05
08:20:55
 | Re: Any other 232 owners?
Congrats crock...
may i ask, how much you paid?
If you don't want to tell public, temm me private.
Or give range.-
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