display_loop.c, uart_commands.c: more reliable "prev" command

src/display_loop.c

@@ -1,5 +1,6 @@
 
 #include <setjmp.h>
+#include <stdbool.h>
 #include <stdio.h>
 
 #include "config.h"
@@ -49,7 +50,7 @@
 #  include "joystick/joystick.h"
 #endif
 
-volatile unsigned char oldMode, oldOldmode, mode;
+volatile unsigned char oldMode, oldOldmode, reverseMode, mode;
 
 jmp_buf newmode_jmpbuf;
 
@@ -77,6 +78,7 @@ void display_loop(){
 		clear_screen(0);
 #endif
 		oldMode = mode;
+
 		switch(mode++) {
 
 #ifdef ANIMATION_SCROLLTEXT
@@ -365,6 +367,14 @@ void display_loop(){
 			off();
 			break;
 #endif
+		default:
+			if (reverseMode) {
+				if (reverseMode-- == (mode - 1)) {
+					mode -= 2;
+				} else {
+					reverseMode = 0;
+				}
+			}
 		}
 	}
 }

src/uart/uart_commands.c

@@ -22,7 +22,8 @@ char g_rx_buffer[UART_BUFFER_SIZE];
 uint8_t g_rx_index;
 
 extern jmp_buf newmode_jmpbuf;
-volatile unsigned char mode;
+extern volatile unsigned char mode;
+extern volatile unsigned char reverseMode;
 
 #if !(defined(eeprom_update_block) && \
 	((E2PAGESIZE == 2) || (E2PAGESIZE == 4) || (E2PAGESIZE == 8)))
@@ -138,12 +139,14 @@ static void uartcmd_next_anim(void) {
 static void uartcmd_prev_anim(void) {
 	uart_puts_p(UART_STR_PROMPT);
 	uartcmd_clear_buffer();
-	if (mode > 1) {
 #ifdef JOYSTICK_SUPPORT
-		if (waitForFire)
+	if (waitForFire) {
+		reverseMode = mode - 2;
 #endif
 		longjmp(newmode_jmpbuf, mode - 2);
+#ifdef JOYSTICK_SUPPORT
 	}
+#endif
 }