From: trenthuber <trenthuber@Trents-HP-Laptop.mynetworksettings.com>
Date: Mon, 23 Jun 2025 10:57:20 +0000 (-0400)
Subject: Initial commit
X-Git-Url: https://trenthuber.com/code?a=commitdiff_plain;h=a4dedf85ba8108658d80f9d439f244470a045273;p=rp2350-tga.git

Initial commit
---

a4dedf85ba8108658d80f9d439f244470a045273
diff --git a/.gitignore b/.gitignore
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index 0000000..378eac2
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+build
diff --git a/CMakeLists.txt b/CMakeLists.txt
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index 0000000..b9d0312
--- /dev/null
+++ b/CMakeLists.txt
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+cmake_minimum_required(VERSION 3.28)
+include(${PICO_SDK_PATH}/external/pico_sdk_import.cmake)
+project(rp2350-tga C CXX ASM)
+
+set(CMAKE_C_STANDARD 11)
+set(CMAKE_CXX_STANDARD 17)
+pico_sdk_init()
+
+add_executable(tga tga.c)
+
+pico_generate_pio_header(tga ../tga.pio)
+
+target_link_libraries(tga pico_stdlib hardware_pio)
+
+pico_add_extra_outputs(tga)
diff --git a/reference/cm5.pdf b/reference/cm5.pdf
new file mode 100644
index 0000000..f968bea
Binary files /dev/null and b/reference/cm5.pdf differ
diff --git a/tga.c b/tga.c
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+++ b/tga.c
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+#include "pico/stdlib.h"
+#include "hardware/pio.h"
+#include "hardware/clocks.h"
+
+#include "tga.pio.h"
+
+int main() {
+	PIO pio;
+	int hsync_offset, vsync_offset;
+
+	pio = pio0;
+	hsync_offset = pio_add_program(pio, &hsync_rgb_program);
+	vsync_offset = pio_add_program(pio, &vsync_i_program);
+
+	vsync_i_program_init(pio, 3, vsync_offset);
+	hsync_rgb_program_init(pio, 0, hsync_offset, RED);
+	hsync_rgb_program_init(pio, 1, hsync_offset, GREEN);
+	hsync_rgb_program_init(pio, 2, hsync_offset, BLUE);
+
+	while (true) {
+		pio_sm_put(pio, 0, -1);
+		pio_sm_put(pio, 1, 0);
+		pio_sm_put(pio, 2, 0);
+		pio_sm_put(pio, 3, -1);
+	}
+}
diff --git a/tga.pio b/tga.pio
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index 0000000..6c3f787
--- /dev/null
+++ b/tga.pio
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+.program hsync_rgb
+.side_set 1
+
+	wait 1 gpio 5 side 0 ; INTENSITY pin
+
+	set x 20 side 0 [13]
+wait_outer:
+	set y 18 side 0
+wait_inner:
+	jmp y-- wait_inner side 0
+	jmp x-- wait_outer side 0
+
+	nop side 0 [15]
+	nop side 0 [15]
+	nop side 0 [15]
+	nop side 1 [15]
+	nop side 1 [15]
+	nop side 0 [15]
+	nop side 0 [15]
+	nop side 0 [15]
+
+	set x 9 side 0 [7]
+outer:
+	out pins 1 side 0
+	set y 13 side 0
+inner:
+	out pins 1 side 0
+	jmp y-- inner side 0
+	out pins 1 side 0
+	jmp x-- outer side 0
+
+% c-sdk {
+enum {
+	HSYNC,
+	VSYNC,
+	RED,
+	GREEN,
+	BLUE,
+	INTENSITY,
+};
+
+static inline void hsync_rgb_program_init(PIO pio, uint sm, uint offset, uint out_pin) {
+	pio_sm_config c;
+	float div;
+
+	pio_gpio_init(pio, out_pin);
+	if (out_pin == RED) pio_gpio_init(pio, HSYNC);
+
+	c = hsync_rgb_program_get_default_config(offset);
+	sm_config_set_out_pins(&c, out_pin, 1);
+	sm_config_set_out_shift(&c, false, true, 32);
+	if (out_pin == RED) sm_config_set_sideset_pins(&c, HSYNC);
+
+	div = clock_get_hz(clk_sys) / 7159157.0f;
+	sm_config_set_clkdiv(&c, div);
+
+	pio_sm_init(pio, sm, offset, &c);
+	pio_sm_set_enabled(pio, sm, true);
+}
+%}
+
+.program vsync_i
+.side_set 1
+
+	set pins 0 side 0 [8]
+	nop side 1 [2]
+	nop side 0 [15]
+	nop side 0 [6]
+
+	set pins 1 side 0
+	set x 14 side 0
+outer:
+	set y 12 side 0
+inner:
+	jmp y-- inner side 0
+	jmp x-- outer side 0
+
+% c-sdk {
+static inline void vsync_i_program_init(PIO pio, uint sm, uint offset) {
+	pio_sm_config c;
+	float div;
+
+	pio_gpio_init(pio, INTENSITY);
+	pio_gpio_init(pio, VSYNC);
+
+	c = hsync_rgb_program_get_default_config(offset);
+	sm_config_set_out_pins(&c, INTENSITY, 1);
+	sm_config_set_sideset_pins(&c, VSYNC);
+
+	div = clock_get_hz(clk_sys) / 15701.0f;
+	sm_config_set_clkdiv(&c, div);
+
+	pio_sm_init(pio, sm, offset, &c);
+	pio_sm_set_enabled(pio, sm, true);
+}
+%}