ZX81 RAM compatibility for replacement
Posted: Wed Mar 13, 2024 9:52 am
Hi all,
I have a ZX81 with white screen. The cursor appears when I use the external 16k memory so should be a RAM problem.
On the board there are the couple of MCM21L14P30 and MCM21L14P45, they differ only for the access time (30ns and 45ns).
Which chip of ram can I use for replacement? All kind of 2114 are good? Are there others full compatible chips? Those on the board should be low consumption (max current 30mA, if I remember well). Let me know, please, I would like to restore the 1k memory since I have the 16k external one.
Thanks in advance
Fabrizio
I have a ZX81 with white screen. The cursor appears when I use the external 16k memory so should be a RAM problem.
On the board there are the couple of MCM21L14P30 and MCM21L14P45, they differ only for the access time (30ns and 45ns).
Which chip of ram can I use for replacement? All kind of 2114 are good? Are there others full compatible chips? Those on the board should be low consumption (max current 30mA, if I remember well). Let me know, please, I would like to restore the 1k memory since I have the 16k external one.
Thanks in advance
Fabrizio