Re: Pin-type RAM for //c

[voss@i40s16.ira.uka.de (Stefan Voss)]

In article <10987POBRTETSGQONYV@wbb.com>, mcfudge@wbb.com (MajorBBS: MCFudge) writes:
|> 
|> I want to expand my Apple //c from 128k to 1152k by adding
|> pin-type RAM under my keyboard.  I have been told that I
|> must remove both my CPU and MMU chips to install the RAM.
|> Under my keyboard I have found that my MMU chip is soldered
|> to the motherboard, but the CPU and MON chips are socketed.
|> Is there any way I will be able to add memory expansion to
|> my //c given what I've found out about the soldered MMU?
|> Thanks in advance for any suggestions you guys have.
|> This is what the motherboard looks like under my keyboard:

In order to have more RAM on your //c you have to install a RAM card.
If you have a newer //c with a memory expansion connector you should
go for one of those cards by Sequential Systems. I am told that they
work very well.

If your //c doesn't have a memory expansion connector your only choice
is a ZRAM Ultra that was made by AE. There a three models of the ZRAM
Ultra: The ZRAM Ultra 1 is just a RAM card, the ZRAM Ultra 2 has a
clock added and the ZRAM Ultra 3 has RAM, a clock and a Z80 CPU for
running CP/M programs.

My //c is equipped with a ZRAM Ultra 2. The installation is a bit
tricky. You have to remove the CPU and the MON chip (Hmm, I'm not sure
about the MON chip) and put them in the empty sockets at the card. 
Then the whole card is plugged into the empty sockets on the
motherboard. This is the tricky and dangerous part because you cannot
actually see if you place the card properly. You have to be very careful.

|> ____________________________________________________________
|>                                     _____IOU______    _____
|>                                    |   344-0021   |  |_RAM_|
|>            ENC                     |______________|   _____
|> KR3600-PRO                                           |_RAM_|
|>  _________________    __________    _____MMU______    _____
|> |                 |  | 342-0132 |  |   344-0011   |  |_RAM_|
|> |_________________|  |__________|  |______________|   _____
|>                      MAP 342-0132                    |_RAM_|
|>                       __________    _____CPU______    _____
|>                     /|342-0033-A| /|    65C02A    |  |_RAM_|
|>                     ||__________| ||______________|   _____
|>                     /__________/  /______________/   |_RAM_|
|> ______________________MON___________________________________

Nice picture indeed.

|> 
|> mcfudge@wbb.com

Regards,

Stefan Voss
(voss@ira.uka.de)