Be consistent with SRAM bank numbering (0-1, not 1-2)

firmware/fast-gpio.h

@@ -19,8 +19,8 @@
 
 #if defined(ARDUINO_ARCH_RP2040)  // e.g. Raspberry Pi Pico (W)
 
-#define SRAM_PIN__WRITE_BANK_1  12
-#define SRAM_PIN__WRITE_BANK_2  13
+#define SRAM_PIN__WRITE_BANK_0  12
+#define SRAM_PIN__WRITE_BANK_1  13
 
 #define SRAM_PIN__ADDR_RESET    15
 #define SRAM_PIN__ADDR_CLOCK    20
@@ -56,8 +56,8 @@
 
 #else
 
+#define SRAM_PIN__WRITE_BANK_0   0
 #define SRAM_PIN__WRITE_BANK_1   0
-#define SRAM_PIN__WRITE_BANK_2   0
 
 #define SRAM_PIN__ADDR_RESET     0
 #define SRAM_PIN__ADDR_CLOCK     0

firmware/sram.cc

@@ -47,8 +47,8 @@ static inline void sram_write_word(uint16_t word_data) {
 
 void sram_init() {
   // Set output modes on all SRAM pins.
+  pinMode(SRAM_PIN__WRITE_BANK_0, OUTPUT);
   pinMode(SRAM_PIN__WRITE_BANK_1, OUTPUT);
-  pinMode(SRAM_PIN__WRITE_BANK_2, OUTPUT);
   pinMode(SRAM_PIN__ADDR_RESET, OUTPUT);
   pinMode(SRAM_PIN__ADDR_CLOCK, OUTPUT);
   pinMode(SRAM_PIN__DATA_NEXT_BIT, OUTPUT);
@@ -60,8 +60,8 @@ void sram_init() {
   FAST_SET(SRAM_PIN__DATA_WRITE);
 
   // Set other outputs low by default.
+  FAST_CLEAR(SRAM_PIN__WRITE_BANK_0);
   FAST_CLEAR(SRAM_PIN__WRITE_BANK_1);
-  FAST_CLEAR(SRAM_PIN__WRITE_BANK_2);
   FAST_CLEAR(SRAM_PIN__ADDR_CLOCK);
   FAST_CLEAR(SRAM_PIN__DATA_NEXT_BIT);
   FAST_CLEAR(SRAM_PIN__DATA_CLOCK);
@@ -72,7 +72,7 @@ void sram_init() {
 void sram_start_bank(int bank) {
   sram_flush_and_release_bank();
 
-  active_bank_pin = bank ? SRAM_PIN__WRITE_BANK_2 : SRAM_PIN__WRITE_BANK_1;
+  active_bank_pin = bank ? SRAM_PIN__WRITE_BANK_1 : SRAM_PIN__WRITE_BANK_0;
   FAST_SET(active_bank_pin);
 
   // Reset the write address to 0.

hardware/README.md

@@ -78,13 +78,13 @@ The stacking boards are:
    - These host the SRAM itself, and the buffers that allow it to be
      alternately controlled by the Sega or the microcontroller.  This is the
      most complex.  A solder jumper on the board selects whether it responds as
-     bank 1 or bank 2.
+     bank 0 or bank 1.
    - When ordering this through JLCPCB:
      - The following parts could easily be populated by hand if you wish:
        - J1 & J2 (stacking headers, 2x26 and 2x21 pins respectively)
      - The following **must** be soldered by hand:
        - JP1 and JP2 are solder jumpers that must be closed on each board; to
-         set bank 1, bridge center to left on both jumpers; to set bank 2,
+         set bank 0, bridge center to left on both jumpers; to set bank 1,
          bridge center to right on both jumpers (also indicated on silkscreen)
  - `microcontroller`: Microcontroller Board
    - This hosts the microcontroller, registers, sync token, and buffers to send

hardware/kinetoscope-header-internal.kicad_sch

@@ -1463,7 +1463,7 @@
 				(pin passive line
 					(at 17.78 -5.08 180)
 					(length 2.54)
-					(name "SRAM_DIS_1"
+					(name "SRAM_DIS_0"
 						(effects
 							(font
 								(size 1.27 1.27)
@@ -1661,7 +1661,7 @@
 				(pin passive line
 					(at 17.78 -7.62 180)
 					(length 2.54)
-					(name "SRAM_DIS_2"
+					(name "SRAM_DIS_1"
 						(effects
 							(font
 								(size 1.27 1.27)
@@ -5558,7 +5558,7 @@
 		)
 		(uuid "57a88da8-613e-47f6-9b56-50c9e2936f6c")
 	)
-	(hierarchical_label "SRAM_DIS_2"
+	(hierarchical_label "SRAM_DIS_1"
 		(shape passive)
 		(at 227.33 49.53 0)
 		(fields_autoplaced yes)
@@ -5582,7 +5582,7 @@
 		)
 		(uuid "62a0af4a-8b7f-4955-b697-aa030e879023")
 	)
-	(hierarchical_label "SRAM_DIS_1"
+	(hierarchical_label "SRAM_DIS_0"
 		(shape passive)
 		(at 227.33 46.99 0)
 		(fields_autoplaced yes)

hardware/libraries/symbols/kinetoscope-cart-header.kicad_sym

@@ -1457,7 +1457,7 @@
 			(pin passive line
 				(at 17.78 -5.08 180)
 				(length 2.54)
-				(name "SRAM_DIS_1"
+				(name "SRAM_DIS_0"
 					(effects
 						(font
 							(size 1.27 1.27)
@@ -1655,7 +1655,7 @@
 			(pin passive line
 				(at 17.78 -7.62 180)
 				(length 2.54)
-				(name "SRAM_DIS_2"
+				(name "SRAM_DIS_1"
 					(effects
 						(font
 							(size 1.27 1.27)

hardware/microcontroller.kicad_pcb

@@ -150,8 +150,8 @@
 	(net 24 "/kinetoscope-header-internal/SEGA_A4")
 	(net 25 "/kinetoscope-header-internal/SEGA_A11")
 	(net 26 "/kinetoscope-header-internal/SEGA_A17")
-	(net 27 "/SRAM_DIS_1")
-	(net 28 "/SRAM_DIS_2")
+	(net 27 "/SRAM_DIS_0")
+	(net 28 "/SRAM_DIS_1")
 	(net 29 "/kinetoscope-header-internal/SEGA_A22")
 	(net 30 "/kinetoscope-header-internal/SEGA_D12")
 	(net 31 "/kinetoscope-header-internal/SEGA_A21")
@@ -12830,8 +12830,8 @@
 			(drill 1)
 			(layers "*.Cu" "*.Mask")
 			(remove_unused_layers no)
-			(net 27 "/SRAM_DIS_1")
-			(pinfunction "SRAM_DIS_1")
+			(net 27 "/SRAM_DIS_0")
+			(pinfunction "SRAM_DIS_0")
 			(pintype "passive")
 			(uuid "78b4b8ae-2d9d-4525-9f47-a095972d8c00")
 		)
@@ -12841,8 +12841,8 @@
 			(drill 1)
 			(layers "*.Cu" "*.Mask")
 			(remove_unused_layers no)
-			(net 28 "/SRAM_DIS_2")
-			(pinfunction "SRAM_DIS_2")
+			(net 28 "/SRAM_DIS_1")
+			(pinfunction "SRAM_DIS_1")
 			(pintype "passive")
 			(uuid "b76a59b6-5cce-4f9d-b2fd-89a388b0933e")
 		)
@@ -17255,7 +17255,7 @@
 			(drill 1)
 			(layers "*.Cu" "*.Mask")
 			(remove_unused_layers no)
-			(net 27 "/SRAM_DIS_1")
+			(net 27 "/SRAM_DIS_0")
 			(pinfunction "GP12")
 			(pintype "passive")
 			(uuid "228c38e5-0736-4437-b7b2-e80c703fe559")
@@ -17266,7 +17266,7 @@
 			(drill 1)
 			(layers "*.Cu" "*.Mask")
 			(remove_unused_layers no)
-			(net 28 "/SRAM_DIS_2")
+			(net 28 "/SRAM_DIS_1")
 			(pinfunction "GP13")
 			(pintype "passive")
 			(uuid "003fc1b7-f515-4979-b3c0-b416078ec299")

hardware/microcontroller.kicad_sch

@@ -4389,7 +4389,7 @@
 		)
 		(uuid "1cd60674-764c-48af-8c72-18a059c4fc89")
 	)
-	(label "SRAM_DIS_1"
+	(label "SRAM_DIS_0"
 		(at 24.13 156.21 180)
 		(fields_autoplaced yes)
 		(effects
@@ -4543,7 +4543,7 @@
 		)
 		(uuid "48096a2c-d096-4e97-abae-1ca3c9b00729")
 	)
-	(label "SRAM_DIS_1"
+	(label "SRAM_DIS_0"
 		(at 35.56 88.9 180)
 		(fields_autoplaced yes)
 		(effects
@@ -4950,7 +4950,7 @@
 		)
 		(uuid "b3064596-2f23-48b8-b19f-be861e2b0da0")
 	)
-	(label "SRAM_DIS_2"
+	(label "SRAM_DIS_1"
 		(at 35.56 91.44 180)
 		(fields_autoplaced yes)
 		(effects
@@ -5247,7 +5247,7 @@
 		)
 		(uuid "eb20dc20-816e-4371-8dc3-efa5c48b6780")
 	)
-	(label "SRAM_DIS_2"
+	(label "SRAM_DIS_1"
 		(at 24.13 158.75 180)
 		(fields_autoplaced yes)
 		(effects
@@ -10147,7 +10147,7 @@
 			)
 			(uuid "6b4575e2-a7da-4f67-8ca7-f82d9304e897")
 		)
-		(pin "SRAM_DIS_2" passive
+		(pin "SRAM_DIS_1" passive
 			(at 33.02 158.75 180)
 			(effects
 				(font
@@ -10157,7 +10157,7 @@
 			)
 			(uuid "68c241c4-745f-4a4f-a1f4-3010418ece04")
 		)
-		(pin "SRAM_DIS_1" passive
+		(pin "SRAM_DIS_0" passive
 			(at 33.02 156.21 180)
 			(effects
 				(font

hardware/sram-bank.kicad_pcb

@@ -178,14 +178,14 @@
 	(net 54 "/kinetoscope-header-internal/SEGA_A22")
 	(net 55 "/SEGA_D6")
 	(net 56 "/SEGA_D1")
-	(net 57 "/SRAM_DIS_2")
+	(net 57 "/SRAM_DIS_1")
 	(net 58 "/SRAM_W_A11")
 	(net 59 "/SRAM_W_A3")
 	(net 60 "/SRAM_W_A1")
 	(net 61 "/SEGA_D0")
 	(net 62 "/SRAM_D_IN12")
 	(net 63 "/SEGA_A12")
-	(net 64 "/SRAM_DIS_1")
+	(net 64 "/SRAM_DIS_0")
 	(net 65 "/SRAM_D_IN14")
 	(net 66 "/SEGA_A17")
 	(net 67 "/SEGA_A5")
@@ -14607,7 +14607,7 @@
 			(at -1.3 0)
 			(size 1 0.5)
 			(layers "F.Cu" "F.Mask")
-			(net 64 "/SRAM_DIS_1")
+			(net 64 "/SRAM_DIS_0")
 			(pinfunction "A")
 			(pintype "passive")
 			(zone_connect 2)
@@ -14652,7 +14652,7 @@
 			(at 1.3 0)
 			(size 1 0.5)
 			(layers "F.Cu" "F.Mask")
-			(net 57 "/SRAM_DIS_2")
+			(net 57 "/SRAM_DIS_1")
 			(pinfunction "B")
 			(pintype "passive")
 			(zone_connect 2)
@@ -17877,8 +17877,8 @@
 			(drill 1)
 			(layers "*.Cu" "*.Mask")
 			(remove_unused_layers no)
-			(net 64 "/SRAM_DIS_1")
-			(pinfunction "SRAM_DIS_1")
+			(net 64 "/SRAM_DIS_0")
+			(pinfunction "SRAM_DIS_0")
 			(pintype "passive")
 			(uuid "3dac3dba-5c3f-4c69-af2a-513ff8511a59")
 		)
@@ -17888,8 +17888,8 @@
 			(drill 1)
 			(layers "*.Cu" "*.Mask")
 			(remove_unused_layers no)
-			(net 57 "/SRAM_DIS_2")
-			(pinfunction "SRAM_DIS_2")
+			(net 57 "/SRAM_DIS_1")
+			(pinfunction "SRAM_DIS_1")
 			(pintype "passive")
 			(uuid "811b3a1b-1c95-4298-9421-8696cf8487e9")
 		)
@@ -18964,7 +18964,7 @@
 			)
 		)
 	)
-	(gr_text "--o bank 1\no-- bank 2"
+	(gr_text "--o bank 0\no-- bank 1"
 		(at 49 28 0)
 		(layer "F.SilkS")
 		(uuid "ff5ec38f-dec0-48ca-bc6a-68fc7aac87d1")

hardware/sram-bank.kicad_sch

@@ -2326,7 +2326,7 @@
 		)
 		(uuid "1ad68464-c13a-4f31-a463-2a50e5cea37d")
 	)
-	(text "These two jumpers need to be soldered the same way.\ne.g.:\n\nSRAM_DIS = SRAM_DIS_1 and ~{SRAM_CE} = ~{SRAM_CE_1}\n\nor\n\nSRAM_DIS = SRAM_DIS_2 and ~{SRAM_CE} = ~{SRAM_CE_2}\n\nThis determines whether the board responds as\nbank 1 (2MB - 3MB range) or bank 2 (3MB - 4MB range)."
+	(text "These two jumpers need to be soldered the same way.\ne.g.:\n\nSRAM_DIS = SRAM_DIS_0 and ~{SRAM_CE} = ~{SRAM_CE_1}\n\nor\n\nSRAM_DIS = SRAM_DIS_1 and ~{SRAM_CE} = ~{SRAM_CE_2}\n\nThis determines whether the board responds as\nbank 0 (2MB - 3MB range) or bank 1 (3MB - 4MB range)."
 		(exclude_from_sim no)
 		(at 17.78 183.896 0)
 		(effects
@@ -2924,7 +2924,7 @@
 		)
 		(uuid "7758da0f-6f21-441a-9041-c6084993ba02")
 	)
-	(label "SRAM_DIS_2"
+	(label "SRAM_DIS_1"
 		(at 261.62 124.46 0)
 		(fields_autoplaced yes)
 		(effects
@@ -2957,7 +2957,7 @@
 		)
 		(uuid "7ce4a0be-ff56-4e5d-a29d-aa1de152b8a1")
 	)
-	(label "SRAM_DIS_1"
+	(label "SRAM_DIS_0"
 		(at 261.62 121.92 0)
 		(fields_autoplaced yes)
 		(effects
@@ -3034,7 +3034,7 @@
 		)
 		(uuid "8feeb3ab-06cf-4a1f-9b42-18b19ae35a0c")
 	)
-	(label "SRAM_DIS_1"
+	(label "SRAM_DIS_0"
 		(at 87.63 181.61 180)
 		(fields_autoplaced yes)
 		(effects
@@ -3078,7 +3078,7 @@
 		)
 		(uuid "b239083f-6144-4fb6-b345-35845484ceae")
 	)
-	(label "SRAM_DIS_2"
+	(label "SRAM_DIS_1"
 		(at 100.33 181.61 0)
 		(fields_autoplaced yes)
 		(effects
@@ -6177,7 +6177,7 @@
 			)
 			(uuid "a8dce3ba-4f5d-4dba-9f49-ac5b9b02e07a")
 		)
-		(pin "SRAM_DIS_2" passive
+		(pin "SRAM_DIS_1" passive
 			(at 259.08 124.46 0)
 			(effects
 				(font
@@ -6187,7 +6187,7 @@
 			)
 			(uuid "6c5e11ad-b452-4d2a-9901-bb528ae7eb02")
 		)
-		(pin "SRAM_DIS_1" passive
+		(pin "SRAM_DIS_0" passive
 			(at 259.08 121.92 0)
 			(effects
 				(font