hw: Connect P2 gamepad input

The user button used to accept the boot prompt as previously used as the P2 input
Now it is the actual P2 gamepad input on the iCEBreaker gamepad PMOD

firmware/boot_defines.S

@@ -19,7 +19,7 @@
 .equ FLASH_SR2_QE, (1 << 1)
 
 .equ PAD_DATA, 0x40000
-.equ PAD_USER_BUTTON, (1 << 1)
+.equ PAD_USER_BUTTON, (1 << 2)
 
 .equ LED_DATA, 0x20000
 

hardware/bus_arbiter.v

@@ -47,7 +47,7 @@ module bus_arbiter #(
     input [31:0] flash_read_data,
     input [15:0] vdp_read_data,
     input [31:0] dsp_read_data,
-    input [1:0] pad_read_data,
+    input [2:0] pad_read_data,
     input [3:0] flash_ctrl_read_data,
     input [7:0] audio_cpu_read_data,
 
@@ -107,7 +107,7 @@ module bus_arbiter #(
         end else if (dsp_en && (READ_SOURCES & `BA_DSP)) begin
             cpu_read_data_ps = dsp_read_data;
         end else if (pad_en && (READ_SOURCES & `BA_PAD)) begin
-            cpu_read_data_ps[1:0] = pad_read_data;
+            cpu_read_data_ps[2:0] = pad_read_data;
         end else if (bootloader_en && (READ_SOURCES & `BA_BOOT)) begin
             cpu_read_data_ps = bootloader_read_data;
         end else if (cpu_ram_en && (READ_SOURCES & `BA_CPU_RAM)) begin

hardware/icebreaker/ics32_top_icebreaker.v

@@ -182,7 +182,9 @@ module ics32_top_icebreaker #(
         .D_OUT_1(flash_clk_ddr[1])
     );
 
-    // --- Gamepad reading ---
+    // --- User inputs ---
+
+    // Gamepads:
 
     wire [1:0] pad_read_data;
 
@@ -192,6 +194,7 @@ module ics32_top_icebreaker #(
             assign pad_read_data = ~pad_read_data_n;
 
             // Gamepad CLK + Latch
+
             SB_IO #(
                 .PIN_TYPE(6'b010100),
                 .PULLUP(1'b0),
@@ -204,15 +207,17 @@ module ics32_top_icebreaker #(
                 .D_OUT_0({pad_clk, pad_latch}),
             );
 
-            // Gamepad data (P1 only for now)
+            // Gamepad data
+
+            // There are actually 4 controller ports on the PMOD but the system is 2P only
 
             SB_IO #(
                 .PIN_TYPE(6'b100000),
                 .PULLUP(1'b0),
                 .NEG_TRIGGER(1'b0),
                 .IO_STANDARD("SB_LVCMOS")
             ) gp_data_sbio [1:0] (
-                .PACKAGE_PIN({ /*pmod2_9, pmod2_3, pmod2_8,*/ btn_u, pmod2_2}),
+                .PACKAGE_PIN({pmod2_8, pmod2_2}),
                 .OUTPUT_ENABLE(1'b0),
                 .INPUT_CLK(clk_2x),
                 .CLOCK_ENABLE(1'b1),
@@ -224,15 +229,15 @@ module ics32_top_icebreaker #(
         end else begin
             // Breakout board buttons:
 
-            wire [3:0] btn_r;
+            wire [2:0] btn_r;
 
             SB_IO #(
                 .PIN_TYPE(6'b100000),
                 .PULLUP(1'b0),
                 .NEG_TRIGGER(1'b0),
                 .IO_STANDARD("SB_LVCMOS")
-            ) btn_sbio [3:0] (
-                .PACKAGE_PIN({btn_u, pmod2_10, pmod2_4, pmod2_9}),
+            ) btn_sbio [2:0] (
+                .PACKAGE_PIN({pmod2_10, pmod2_4, pmod2_9}),
                 .OUTPUT_ENABLE(1'b0),
                 .INPUT_CLK(clk_2x),
                 .CLOCK_ENABLE(1'b1),
@@ -242,13 +247,10 @@ module ics32_top_icebreaker #(
                 .OUTPUT_CLK(clk_2x)
             );
 
-            // Only the 3 buttons on the breakboard are used as a partial gamepad
-            // This can be extended later with an actual gamepad PMOD
+            // P1 has limited inputs using the breakout board
 
             wire [11:0] pad_btn = {btn_r[0], btn_r[2], 5'b0, btn_r[1]};
 
-            assign pad_read_data[1] = ~btn_r[3];
-
             mock_gamepad mock_gamepad(
                 .clk(clk_2x),
 
@@ -258,9 +260,34 @@ module ics32_top_icebreaker #(
 
                 .pad_out(pad_read_data[0])
             );
+
+            // P2 has no inputs when just using the breakout board
+
+            assign pad_read_data[1] = 0;
         end
     endgenerate
 
+    // User button:
+
+    wire user_button;
+    wire user_button_n = !user_button;
+
+    SB_IO #(
+        .PIN_TYPE(6'b100000),
+        .PULLUP(1'b0),
+        .NEG_TRIGGER(1'b0),
+        .IO_STANDARD("SB_LVCMOS")
+    ) btn_sbio (
+        .PACKAGE_PIN(btn_u),
+        .OUTPUT_ENABLE(1'b0),
+        .INPUT_CLK(clk_2x),
+        .CLOCK_ENABLE(1'b1),
+        .D_IN_0(user_button),
+
+        // This isn't used but nextpnr will error without this:
+        .OUTPUT_CLK(clk_2x)
+    );
+
     // --- icestation-32 ---
 
     wire reset_1x, reset_2x;
@@ -306,6 +333,8 @@ module ics32_top_icebreaker #(
         .pad_clk(pad_clk),
         .pad_data(pad_read_data),
 
+        .user_button(user_button_n),
+
         .led({led_r, led_b}),
 
         .flash_clk_ddr(flash_clk_ddr),

hardware/ics32.v

@@ -46,6 +46,8 @@ module ics32 #(
     output pad_clk,
     input [1:0] pad_data,
 
+    input user_button,
+
     output [1:0] flash_clk_ddr,
     output flash_csn,
     output [3:0] flash_in,
@@ -553,7 +555,7 @@ module ics32 #(
         .flash_read_data(flash_read_data),
         .dsp_read_data(dsp_result),
         .vdp_read_data(vdp_read_data),
-        .pad_read_data(pad_data),
+        .pad_read_data({user_button, pad_data}),
         .flash_ctrl_read_data(flash_ctrl_read_data),
         .audio_cpu_read_data(audio_ctrl_cpu_read_data),
 

hardware/ulx3s/ics32_top_ulx3s.v

@@ -246,11 +246,7 @@ module ics32_top_ulx3s #(
     wire [11:0] pad_btn;
     wire [1:0] pad_read_data;
 
-    // P2 input is used as a special user button
-    // (This needs to move if an actual P2 is needed)
-
-    wire btn_u = btn[3];
-    assign pad_read_data[1] = btn_u;
+    // P1 is supported using the gamepad_state instance below
 
     mock_gamepad mock_gamepad(
         .clk(clk_2x),
@@ -262,9 +258,15 @@ module ics32_top_ulx3s #(
         .pad_out(pad_read_data[0])
     );
 
+    // P2 currently not supported on ULX3S
+
+    assign pad_read_data[1] = 0;
+
     // The mock_gamepad above is driven by gamepad data from one of the sources below.
     // GAMEPAD_SOURCE is used to detmine which one:
 
+    wire user_button;
+
     ulx3s_gamepad_state #(
         .GAMEPAD_SOURCE(GAMEPAD_SOURCE),
         .USB_GAMEPAD(USB_GAMEPAD)
@@ -303,6 +305,21 @@ module ics32_top_ulx3s #(
         .pad_btn(pad_btn)
     );
 
+    // Unlike the gamepads, user button input is always provided by PCB
+    // btn[0] is shared with the ESP32 reset if (GAMEPAD_SOURCE == "BLUETOOTH")
+
+    wire user_button;
+
+    debouncer #(
+        .BTN_COUNT(1)
+    ) user_button_debouncer (
+        .clk(clk_2x),
+        .reset(reset_2x),
+
+        .btn(!btn[0]),
+        .level(user_button)
+    );
+
     // --- icestation-32 ---
 
     assign led = GAMEPAD_LED ? pad_btn : status_led;
@@ -350,6 +367,8 @@ module ics32_top_ulx3s #(
         .pad_clk(pad_clk),
         .pad_data(pad_read_data),
 
+        .user_button(user_button),
+
         .led(status_led),
 
         .flash_clk_ddr(flash_clk_ddr),

hardware/ulx3s/ulx3s_gamepad_state.v

@@ -72,7 +72,7 @@ module ulx3s_gamepad_state #(
                 .reset(reset),
 
                 .btn(!btn[0]),
-                .level(esp32_reset),
+                .level(esp32_reset)
             );
 
             // SPI gamepad reader:

simulator/CXXRTLSimulation.cpp

@@ -133,7 +133,7 @@ void CXXRTLSimulation::step(uint64_t time) {
     top.p_clk__1x = value<1>{clk_1x};
     top.p_clk__2x = value<1>{clk_2x};
 
-    top.p_btn__u.set(!button_user);
+    top.p_btn__u.set(button_user);
     top.p_btn__1.set(button_1);
     top.p_btn__2.set(button_2);
     top.p_btn__3.set(button_3);

simulator/VerilatorSimulation.cpp

@@ -35,7 +35,7 @@ void VerilatorSimulation::step(uint64_t time) {
     tb->clk_1x = clk_1x;
     tb->clk_2x = clk_2x;
 
-    tb->btn_u = !button_user;
+    tb->btn_u = button_user;
     tb->btn_1 = button_1;
     tb->btn_2 = button_2;
     tb->btn_3 = button_3;

simulator/ics32_tb.v

@@ -72,6 +72,8 @@ module ics32_tb(
         .pad_clk(pad_clk),
         .pad_data(pad_read_data),
 
+        .user_button(btn_u),
+
         .led(led),
 
         .flash_clk_ddr(flash_clk_ddr),
@@ -97,10 +99,11 @@ module ics32_tb(
     };
 
     wire [1:0] pad_read_data;
-    assign pad_read_data[1] = ~btn_u;
 
     wire pad_latch, pad_clk;
 
+    // P1 is currently controllable in the sim
+
     mock_gamepad mock_gamepad(
         .clk(clk_2x),
 
@@ -111,6 +114,11 @@ module ics32_tb(
         .pad_out(pad_read_data[0])
     );
 
+    // P2 isn't
+
+    assign pad_read_data[1] = 0;
+
+
     // --- Flash sim blackbox ---
 
     wire [1:0] flash_clk_ddr;

software/gamepad_test/main.c

@@ -57,6 +57,9 @@ int main() {
     const uint8_t p2_base_x = 60;
     const uint8_t p2_base_y = 10;
 
+    const uint8_t user_base_x = 47;
+    const uint8_t user_base_y = 25;
+
     while (true) {
         vdp_wait_frame_ended();
 
@@ -67,6 +70,11 @@ int main() {
 
         vp_printf(p2_base_x, p2_base_y, TEXT_PALETTE_ID, SCROLL0, MAP_VRAM_BASE, "Player 2");
         print_gamepad(p2_current, p2_base_x, p2_base_y + 2);
+
+        vp_printf(user_base_x, user_base_y,
+                  TEXT_PALETTE_ID, SCROLL0, MAP_VRAM_BASE,
+                  "User button: %d",
+                  pad_read_user_button());
     }
 }
 

software/lib/gamepad.c

@@ -14,6 +14,7 @@ static volatile uint32_t * const PAD_BASE = (uint32_t *)0x40000;
 
 static const uint32_t PAD_LATCH = 1 << 0;
 static const uint32_t PAD_CLK = 1 << 1;
+static const uint32_t USER_BUTTON = 1 << 2;
 
 #define PAD_IO (*((volatile uint32_t *) PAD_BASE + 0))
 
@@ -73,6 +74,10 @@ void pad_decode_input(uint16_t encoded_input, PadInputDecoded *decoded_input) {
     }
 }
 
+bool pad_read_user_button() {
+    return (PAD_IO & USER_BUTTON);
+}
+
 const PadInputDecoded PAD_INPUT_DECODED_NO_INPUT = {
     .b = 0, .y = 0, .select = 0, .start = 0,
     .up = 0, .down = 0, .left = 0, .right = 0,

software/lib/gamepad.h

@@ -45,4 +45,6 @@ extern const PadInputDecoded PAD_INPUT_DECODED_NO_INPUT;
 void pad_read(uint16_t *p1_current, uint16_t *p2_current, uint16_t *p1_edge, uint16_t *p2_edge);
 void pad_decode_input(uint16_t encoded_input, PadInputDecoded *decoded_input);
 
+bool pad_read_user_button(void);
+
 #endif /* gamepad_h */