PENTAGON 1024 - disable 1MB

[Black_Cat]

Screens of 128K are in pages 5 and 7. If A17', A18' and A19' are not zero you cannot access these pages in upper CPU window. This means incompatibility.

Dima, is incorrect remark. Selection of upper adress lines is determined by the logic of the program. If the program does not use both screens, then A17'-A19' can be arbitrary. Otherwise they should be set to zero. As you can see no incompatibility there.

---------- Post added at 15:05 ---------- Previous post was at 14:39 ----------

Dima, before making the statement, first carefully studied the scheme for memory expansion up to 1Mb in the Pentagon-128. From this scheme follows that the management of Pentagon-1024SL v2.2 and Unreal implemented incorrectly. If the management is implemented correctly, the result should be as follows:
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