From 84c5da36bab8be29c2e42002995bd2b5ba2d0f53 Mon Sep 17 00:00:00 2001
From: Erin Shepherd <erin.shepherd@e43.eu>
Date: Sun, 23 Apr 2023 23:18:58 +0200
Subject: [PATCH] Setup stdio to use RTT for debug purposes

---
 .gitmodules     |  3 +++
 CMakeLists.txt  |  6 ++++++
 lib/rtt         |  1 +
 shell.nix       |  2 +-
 src/main.c      |  8 ++++++--
 src/stdio_rtt.c | 20 ++++++++++++++++++++
 src/stdio_rtt.h |  8 ++++++++
 7 files changed, 45 insertions(+), 3 deletions(-)
 create mode 160000 lib/rtt
 create mode 100644 src/stdio_rtt.c
 create mode 100644 src/stdio_rtt.h

diff --git a/.gitmodules b/.gitmodules
index 97478eb..aa70eb1 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,3 +1,6 @@
 [submodule "lib/pico-sdk"]
 	path = lib/pico-sdk
 	url = https://github.com/raspberrypi/pico-sdk
+[submodule "lib/rtt"]
+	path = lib/rtt
+	url = https://github.com/adfernandes/segger-rtt
diff --git a/CMakeLists.txt b/CMakeLists.txt
index ce9aac0..a86bed1 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -7,7 +7,13 @@ project(vibe-check)
 
 pico_sdk_init()
 
+include_directories(
+    ${CMAKE_SOURCE_DIR}/lib/rtt/RTT
+)
+
 add_executable(vibe-check
+    lib/rtt/RTT/SEGGER_RTT.c
+    src/stdio_rtt.c
     src/main.c
 )
 
diff --git a/lib/rtt b/lib/rtt
new file mode 160000
index 0000000..660fa25
--- /dev/null
+++ b/lib/rtt
@@ -0,0 +1 @@
+Subproject commit 660fa2589a67cc87c9a112e405531c53b77504ad
diff --git a/shell.nix b/shell.nix
index 90b9e68..8f45b57 100644
--- a/shell.nix
+++ b/shell.nix
@@ -1,7 +1,7 @@
 { pkgs ? import <nixpkgs> {} }:
 pkgs.mkShell {
   buildInputs = with pkgs; [
-    cmake ninja python3 gcc-arm-embedded
+    cmake cmakeCurses ninja python3 gcc-arm-embedded
     picotool
   ];
 }
diff --git a/src/main.c b/src/main.c
index 0ec3f09..8326976 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1,7 +1,9 @@
 #include <stdio.h>
 #include "pico/stdlib.h"
 #include "pico/cyw43_arch.h"
-#include "btstack.h"
+#include "stdio_rtt.h"
+
+// #include "btstack.h"
 
 #ifndef CYW43_WL_GPIO_LED_PIN
     #error no WiFi LED on board, wrong -DPICO_BOARD?
@@ -11,7 +13,9 @@
 // https://github.com/buttplugio/buttplug/blob/master/buttplug/src/server/device/protocol/sakuraneko.rs
 
 int main() {
-    stdio_init_all();
+    // stdio_init_all();
+    stdio_rtt_init();
+
     if (cyw43_arch_init()) {
         printf("WiFi init failed");
         return -1;
diff --git a/src/stdio_rtt.c b/src/stdio_rtt.c
new file mode 100644
index 0000000..8cbb060
--- /dev/null
+++ b/src/stdio_rtt.c
@@ -0,0 +1,20 @@
+#include "pico/stdio/driver.h"
+#include "stdio_rtt.h"
+#include "SEGGER_RTT.h"
+
+void stdio_rtt_init(void) {
+    stdio_set_driver_enabled(&stdio_rtt, true);
+}
+
+static void stdio_rtt_out_chars(const char *buf, int length) {
+    SEGGER_RTT_Write(0, buf, length);
+}
+
+static int stdio_rtt_in_chars(char *buf, int length) {
+    return SEGGER_RTT_Read(0, buf, length);
+}
+
+stdio_driver_t stdio_rtt = {
+    .out_chars = stdio_rtt_out_chars,
+    .in_chars = stdio_rtt_in_chars,
+};
diff --git a/src/stdio_rtt.h b/src/stdio_rtt.h
new file mode 100644
index 0000000..f3fd837
--- /dev/null
+++ b/src/stdio_rtt.h
@@ -0,0 +1,8 @@
+#ifndef STDIO_RTT_H
+#define STDIO_RTT_H
+#include "pico/stdio.h"
+
+extern stdio_driver_t stdio_rtt;
+void stdio_rtt_init(void);
+
+#endif