Differences

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--- notes:flashcart:scgba [2023/10/14 14:04] – asie
+++ notes:flashcart:scgba [2025/03/30 09:16] (current) – asie
@@ Line 1: / Line 1: @@
 ====== SuperCard (GBA) programming ======
+===== All models =====
+==== SC_MODE (0x9FFFFFE) ====
+To unlock this register, one must write **0xA55A** to it first.
+<code>
+       bit       0
+ ---- ---- ---- ----
+ ???? ???? ???? ?wsm
+                 |||
+                 ||+- Map registers
+                 |+-- CF/SD enable
+                 +--- PSRAM write enable
+                      Also swaps SRAM bank (2 x 64 KB)
+</code>
 ===== CompactFlash models =====
@@ Line 5: / Line 22: @@
 For CompactFlash card access, the SuperCard CF mimics [[notes:flashcart:gbamp|the GBA Movie Player interface]].
-===== Memory-mapped I/O =====
+===== SD models =====
-==== SCCF_MODE (0x9FFFFFE) ====
+==== SCSD_DATA_WR (0x900000x) ====
-To unlock this register, one must write **0xA55A** to it first.
+SD card 4-bit data bus writes.
 <code>
        bit       0
- ???? ???? ???? ?mm?
+ ---- ---- ---- ----
-                 ||
+ oooo .... .... ....
-                 ++- Mode:
+ ||||
- - ?
+ ++++---------------- Written value.
- - CompactFlash
- - ?
- - ?
 </code>
+==== SCSD_DATA_RD (0x910000x) ====
+SD card 4-bit data bus reads.
+TODO: Most likely operates as a 16-bit shift register. This means that, to read sixteen bits in order, the address must be accessed four times.
+<code>
+       bit       0
+ ---- ---- ---- ----
+ oooo .... .... ....
+ ||||
+ ++++---------------- Written value.
+</code>
+==== SCSD_CMD (0x9800000) ====
+SD card 1-bit command bus.
+<code>
+       bit       0
+ ---- ---- ---- ----
+ .... ..?? o... ...i
+        || |       |
+        || |       +- Input (from card)
+        || |
+        || +--------- Output (to card)
+        ||
+        ++----------- Related to card insertion?
+</code>
+===== SuperCard Lite =====
+==== SCLT_ENABLE (0x9440000) ====
+===== See also =====
+  * [[https://github.com/davidgfnet/supercard-pcb-reverse|SuperCard PCB scans and datasheet archive]]
+  * [[https://html-preview.github.io/?url=https://github.com/davidgfnet/gba-supercard-cpld/blob/master/report.html|SuperCard CPLD dump report]]