From a3e75061cac23b324ab8cc6d80d8ab26dc770616 Mon Sep 17 00:00:00 2001
From: Michael Davidsaver <mdavidsaver@gmail.com>
Date: Thu, 15 Jan 2026 15:41:28 -0800
Subject: [PATCH] console: disable interrupts around msg count and char buffer

Ensure consistency between console_service() in task context
and CONSOLE_USART_ISR() by disabling interrupts when the task
is accessing counters/indices maniuplated by both.
---
 src/console.c | 23 +++++++++++++++++++----
 1 file changed, 19 insertions(+), 4 deletions(-)

diff --git a/src/console.c b/src/console.c
index ae125b9..7c7987f 100644
--- a/src/console.c
+++ b/src/console.c
@@ -84,6 +84,7 @@ const char *menu_str[] = {"\r\n",
 };
 #define MENU_LEN (sizeof(menu_str)/sizeof(*menu_str))
 
+// number of UART_MSG_TERMINATOR in UARTQUEUE
 static uint8_t _msgCount;
 static uint8_t _fpgaEnable;
 
@@ -719,11 +720,23 @@ void CONSOLE_USART_ISR(void) {
   return;
 }
 
+// call only from ISR
 void console_pend_msg(void) {
   _msgCount++;
   return;
 }
 
+static bool console_dequeue_msg(void) {
+  bool ret = false;
+  INTERRUPTS_DISABLE();
+  if(_msgCount) {
+    _msgCount--;
+    ret = true; // caller must console_shift_msg()
+  }
+  INTERRUPTS_ENABLE();
+  return ret;
+}
+
 /*
  * int console_service(void);
  *  Service the console system.
@@ -732,9 +745,8 @@ void console_pend_msg(void) {
 int console_service(void) {
   uint8_t msg[CONSOLE_MAX_MESSAGE_LENGTH];
   int len;
-  if (_msgCount) {
+  if (console_dequeue_msg()) {
     len = console_shift_msg(msg);
-    _msgCount--;
     if (len) {
       return console_handle_msg((char *)msg, len);
     }
@@ -767,8 +779,11 @@ static int console_shift_all(uint8_t *pData) {
  *  Returns the number of bytes shifted out.
  */
 static int console_shift_msg(uint8_t *pData) {
-  //UARTQUEUE_ShiftOut(pData, CONSOLE_MAX_MESSAGE_LENGTH);
-  return UARTQUEUE_ShiftUntil(pData, UART_MSG_TERMINATOR, CONSOLE_MAX_MESSAGE_LENGTH);
+  int ret;
+  INTERRUPTS_DISABLE();
+  ret = UARTQUEUE_ShiftUntil(pData, UART_MSG_TERMINATOR, CONSOLE_MAX_MESSAGE_LENGTH);
+  INTERRUPTS_ENABLE();
+  return ret;
 }
 
 static int xatoi(char c) {