Support for 1 Mbit Mask ROM @DIP28 MX23C1000, HN62321

vriviere

Hi, I would like that you add support on the TL866II to read 1 Mbit Mask ROMs in DIP28 packages. They were used in computers and game devices in the early 90's.

This includes the following references (click for datasheets):
- Macronix MX23C1000
- Hitachi HN62321

As I understand, they are similar to 27C512 chips, except that pin 22 is used for an extra A16 line, instead of the OE signal. Of course, such mask ROM can only operate in read-only mode.

I tried to read one of the Atari STe ROMs (128 KB) with TL866II/Xgpro using AM27C512 settings. It works as expected, but of course I only get the first half of the ROM (64 KB) as it lacks proper A16 handling.

I guess that adding support for such devices would be very easy for you, and it would be great help for all people involved into software preservation.

vriviere

You mean making a hardware adapter?

admin

回复 1# vriviere
For TL866II, it is not easy, need to rewrite all the code。
you can read twice.      
    first :  Assign A16= GND     
    then:  Assign A16= VCC.