Differences

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--- memory_map [2022/08/19 10:48] – [IO registers] pulkomandy
+++ memory_map [2023/04/16 10:15] (current) – [External bus configuration] pulkomandy
@@ Line 214: / Line 214: @@
      * 00 - Map entire range to ROMCSB
      * 01 - Map ''0x4000 - 0x1fffff'' to ROMCSB, ''0x200000 - 0x3fffff'' to CSB1
-     * 1x - Map ''0x4000 - 0x0fffff'' to ROMCSB, ''0x100000 - 0x1fffff'' to CSB1, ''0x200000 - 0x2fffff'' to CSB2, ''0x300000 - 0x3fffff'' to CSB1
+     * 1x - Map ''0x4000 - 0x0fffff'' to ROMCSB, ''0x100000 - 0x1fffff'' to CSB1, ''0x200000 - 0x2fffff'' to CSB2, ''0x300000 - 0x3fffff'' to CSB3
    * Bits 5-3: Bus arbitration priority control
      * 101 - 1. Audio, 2. PPU, 3. CPU
@@ Line 222: / Line 222: @@
 External RAM mapping overrides any ROM mapping.
+On the V.Smile, both ROMCSB and CSB1 allow to access the cartridge ROM. This means bit 6 is not very useful.
+CSB2 is the cartridge RAM, and CSB3 is the system ROM. They are both enabled at the same time by using bit 7.
 ==== ADC ====