Next Memory Bank Select: Difference between revisions
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|Number=$DFFD | |Number=$DFFD | ||
|ShortDesc=Provides additional bank select bits for extended memory. | |ShortDesc=Provides additional bank select bits for extended memory. | ||
|Readable= | |Readable=No | ||
|Writable= | |Writable=Yes | ||
|Subsystem=Memory map | |Subsystem=Memory map | ||
|PortMask=%1101 1111 1111 1101 | |PortMask=%1101 1111 1111 1101 | ||
}} | }} | ||
bits 3:0 = most significant bits of the 16K RAM bank selected in {{PortNo|$7FFD}} | |||
Port 0xDFFD bits 3:0 are combined as the highest bits with the bank selected in port 0x7FFD to form a 7-bit bank number. | |||
Revision as of 10:16, 31 December 2019
| Port Number | $DFFD |
|---|---|
| Decimal | |
| Short desc. | Provides additional bank select bits for extended memory. |
| Bit Mask | %1101 1111 1111 1101 |
| Readable | No |
| Writable | Yes |
| Subsystem | Memory map |
bits 3:0 = most significant bits of the 16K RAM bank selected in NextPort:$7FFD
Port 0xDFFD bits 3:0 are combined as the highest bits with the bank selected in port 0x7FFD to form a 7-bit bank number.