Differences

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--- sst-6809:memory_map [2025/03/16 20:52] – split memory latch select 256b to its own page robert
+++ sst-6809:memory_map [2025/04/12 11:34] (current) – robert
@@ Line 10: / Line 10: @@
 | ::: |  EC00 - EEFF  | unassigned |
 | ::: |  EF00 - EFFF  | [[Memory Latch Select 256b]] |
-| ROM |  F000 - FFFF  | [[#EEPROM 4K]] |
+| ROM |  F000 - FFFF  | [[EEPROM 4K]] |
 | ::: |  F000 - F3FF  | [[ASSIST09]] Expansion ROM area (unused) |
 | ::: |  F800 - FFFF  | [[ASSIST09]] |
-| MPU |  FFF0 - FFF1  | HD6390 Illegal Opcode/Divide By Zero Trap vector (FFD4) |
+| MPU |  FFF0 - FFF1  | HD6309 Illegal Opcode/Divide By Zero Trap vector (FFD4) |
 | ::: |  FFF2 - FFF3  | SWI3 vector (FFD8) |
 | ::: |  FFF4 - FFF5  | SWI2 vector (FFDC)|
@@ Line 27: / Line 27: @@
 These use J3 select jumper for 8xxx - Exxx address select range
-===== EEPROM 4K =====
-The SST-6809 contains a 32KB EEPROM.
-The Memory Latch Select allows mapping one of eight 4KB sections of the EEPROM into the memory range $F000-$FFFF which includes the MPU interrupt vectors.
-Make use of the boot ROM select jumper(s).
-The 2.0 can boot from 4 different segments, the 2.1 only 2.
-But the current EEPROM only has ASSIST09 burned into it.
-The "external ROM" is just the unused space in the other half of the 4k boot ROM.
-Ken just never put anything there.
-At some point Ken could burn another boot into an EEPROM.
-The PTM on the Mezz board can support tracing with ASSIST09, but it needs a jumper to put its interrupt on NMI.
 Return to [[:SST-6809:]]

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