From e7e436affac5d40f62f3390e89a6db600d10ae9e Mon Sep 17 00:00:00 2001
From: Hector van der Aa <hector@h3cx.dev>
Date: Tue, 2 Jun 2026 17:29:46 +0200
Subject: [PATCH] Updated ring buffer

Updated ring buffer to match use case, one write head with negative read
index
---
 STM32/CM7/CMakeLists.txt         |  1 +
 STM32/CM7/Core/Inc/ring_buffer.h |  3 +--
 STM32/CM7/Core/Src/ring_buffer.c | 15 ++-------------
 3 files changed, 4 insertions(+), 15 deletions(-)

diff --git a/STM32/CM7/CMakeLists.txt b/STM32/CM7/CMakeLists.txt
index c9241eb..36b9eae 100644
--- a/STM32/CM7/CMakeLists.txt
+++ b/STM32/CM7/CMakeLists.txt
@@ -59,6 +59,7 @@ target_include_directories(${CMAKE_PROJECT_NAME} PRIVATE
 # Add sources to executable
 target_sources(${CMAKE_PROJECT_NAME} PRIVATE
     # Add user sources here
+    Core/Src/ring_buffer.c
 )
 
 # Link directories setup
diff --git a/STM32/CM7/Core/Inc/ring_buffer.h b/STM32/CM7/Core/Inc/ring_buffer.h
index 70e808e..17590d7 100644
--- a/STM32/CM7/Core/Inc/ring_buffer.h
+++ b/STM32/CM7/Core/Inc/ring_buffer.h
@@ -6,9 +6,8 @@
 typedef struct ring_buffer_t {
   uint32_t buffer[256];
   uint8_t w_head;
-  uint8_t r_head;
 } ring_buffer_t;
 
 inline void ringBufferPush(ring_buffer_t *rb, uint32_t value);
 
-inline int ringBufferPop(ring_buffer_t *rb, uint32_t *output);
+inline uint32_t ringBufferRead(ring_buffer_t *rb, uint8_t idx);
diff --git a/STM32/CM7/Core/Src/ring_buffer.c b/STM32/CM7/Core/Src/ring_buffer.c
index 22b904c..c55b86c 100644
--- a/STM32/CM7/Core/Src/ring_buffer.c
+++ b/STM32/CM7/Core/Src/ring_buffer.c
@@ -9,20 +9,9 @@
 inline void ringBufferPush(ring_buffer_t *rb, uint32_t value) {
   rb->buffer[rb->w_head] = value;
   rb->w_head++;
-  if (rb->w_head == rb->r_head) {
-    // if write head catches up to read head, crash program as consumer task
-    // should keep up with write head
-    assert(false);
-  }
   return;
 }
 
-inline int ringBufferPop(ring_buffer_t *rb, uint32_t *output) {
-  if (rb->w_head == rb->r_head) {
-    // if read head is at write head, buffer is empty so nothing to pop
-    return 1;
-  }
-  *output = rb->buffer[rb->r_head];
-  rb->r_head++;
-  return 0;
+inline uint32_t ringBufferRead(ring_buffer_t *rb, uint8_t idx) {
+  return rb->buffer[rb->w_head - 1 - idx];
 }