This page (revision-8) was last changed on 11-Apr-2023 13:20 by matosimi 

This page was created on 09-Sep-2015 16:06 by Florian Dingler

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Version Date Modified Size Author Changes ... Change note
8 11-Apr-2023 13:20 3 KB matosimi to previous
7 11-Apr-2023 11:37 2 KB matosimi to previous | to last
6 03-Feb-2023 15:21 2 KB Florian Dingler to previous | to last
5 21-Mar-2017 23:08 2 KB Florian Dingler to previous | to last
4 02-Nov-2015 19:58 2 KB Florian Dingler to previous | to last
3 11-Oct-2015 20:20 2 KB Florian Dingler to previous | to last
2 09-Sep-2015 16:08 1 KB Florian Dingler to previous | to last
1 09-Sep-2015 16:06 1 KB Florian Dingler to last

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Difference between version and

At line 28 changed one line
!!!For 600XL, 800XL, 1200XL, 130XE
!!!For 600XL, 800XL, 1200XL
At line 55 changed one line
130XE
!!!For 130XE
Bits 2,3,4,5 set the behavior of extended RAM which is always mapped to $4000-$7FFF area.
At line 59 changed 4 lines
|5|ANTIC|0=ANTIC has access to extra RAM, 1=ANTIC has access to normal RAM
|4|CPU|0=CPU has access to extra RAM, 1=CPU has access to normal RAM
|3|$4000-$7FFF Bank select|see below
|2|$4000-$7FFF Bank select|see below
|5|ANTIC|0=ANTIC has access to extended RAM, 1=ANTIC has access to main RAM
|4|CPU|0=CPU has access to extended RAM, 1=CPU has access to main RAM
|3|$4000-$7FFF|Bank selection bit
|2|$4000-$7FFF|Bank selection bit
At line 66 changed 6 lines
Bank select - One bank occupies 16KB area from $4000-$7FFF
||Bit 2||Bit 3||Bank
|0|0|Bank 0
|0|1|Bank 1
|1|0|Bank 2
|1|1|Bank 3
Compatibility mode (only main bank enabled)
||Bit 5 ||Bit 4 ||Bit 3 ||Bit 2 ||CPU accesses ||ANTIC accesses
|VBE |CPE |Bank selection|Bank selection| |
|1 |1 |doesn't matter|doesn't matter|M $4000-$7FFF| M $4000-$7FFF
At line 72 added 24 lines
CPU extended RAM mode
||Bit 5 ||Bit 4 ||Bit 3 ||Bit 2 ||CPU accesses ||ANTIC accesses
|VBE |CPE |Bank selection |Bank selection| |
|1 |0 |0 |0 |E $0000-$3FFF |M $4000-$7FFF
|1 |0 |0 |1 |E $4000-$7FFF |M $4000-$7FFF
|1 |0 |1 |0 |E $8000-$BFFF |M $4000-$7FFF
|1 |0 |1 |1 |E $C000-$FFFF |M $4000-$7FFF
Video (ANTIC) extended RAM mode
||Bit 5 ||Bit 4 ||Bit 3 ||Bit 2 ||CPU accesses ||ANTIC accesses
|VBE |CPE |Bank selection|Bank selection| |
|0 |1 |0 |0 |M $4000-$7FFF |E $0000-$3FFF
|0 |1 |0 |1 |M $4000-$7FFF |E $4000-$7FFF
|0 |1 |1 |0 |M $4000-$7FFF |E $8000-$BFFF
|0 |1 |1 |1 |M $4000-$7FFF |E $C000-$FFFF
General extended RAM Mode
||Bit 5 ||Bit 4 ||Bit 3 ||Bit 2 ||CPU accesses ||ANTIC accesses
|VBE |CPE |Bank selection|Bank selection| |
|0 |0 |0 |0 |E $0000-$3FFF |E $0000-$3FFF
|0 |0 |0 |1 |E $4000-$7FFF |E $4000-$7FFF
|0 |0 |1 |0 |E $8000-$BFFF |E $8000-$BFFF
|0 |0 |1 |1 |E $C000-$FFFF |E $C000-$FFFF
This page (revision-8) was last changed on 11-Apr-2023 13:20 by matosimi  Top