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authorH. Peter Anvin <hpa@zytor.com>2014-06-11 07:05:40 (GMT)
committerH. Peter Anvin <hpa@zytor.com>2014-06-11 07:05:40 (GMT)
commita6a1600daa977d4f97f7e02a7499e1236afe54e9 (patch)
treef6801181ad277b1ecc7ac31614e7cd5cec3a7dcf
parentd3ea857627ddea85e0a1035e37ded5ca5870ab99 (diff)
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CHANGES: Document that execute map is no longer supported
The execute map never worked right (immediate fetching is NOT done in the M1 cycle) so just drop it. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
-rw-r--r--CHANGES4
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diff --git a/CHANGES b/CHANGES
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--- a/CHANGES
+++ b/CHANGES
@@ -41,6 +41,10 @@ Changes in release DE1-19:
someone who actually did Mikrodator's 64K would have done to support
CP/M, too.
+* Bits [5:4] of I/O port 132 (MMU control) are not supported anymore;
+ they never worked right anyway. Only read and write control are now
+ supported. Writing port 7 still sets both read and write.
+
Changes in release DE1-18:
--------------------------