From 69aaf5d096e96639a8951854bf6e00ef7f7d9fdd Mon Sep 17 00:00:00 2001
From: revilor <oliver.rossmueller@web.de>
Date: Wed, 6 Feb 2019 03:56:22 +0100
Subject: [PATCH] MMU2 fixes (#13082)

---
 Marlin/src/feature/prusa_MMU2/mmu2.cpp | 39 +++++++++++++-------------
 Marlin/src/feature/prusa_MMU2/mmu2.h   | 14 ++++++++-
 2 files changed, 32 insertions(+), 21 deletions(-)

diff --git a/Marlin/src/feature/prusa_MMU2/mmu2.cpp b/Marlin/src/feature/prusa_MMU2/mmu2.cpp
index 5bdd4dde4..aebd0ad9d 100644
--- a/Marlin/src/feature/prusa_MMU2/mmu2.cpp
+++ b/Marlin/src/feature/prusa_MMU2/mmu2.cpp
@@ -38,10 +38,6 @@ MMU2 mmu2;
 #include "../../module/stepper_indirection.h"
 #include "../../Marlin.h"
 
-#if ENABLED(FILAMENT_RUNOUT_SENSOR)
-  #include "../runout.h"
-#endif
-
 #define MMU_TODELAY 100
 #define MMU_TIMEOUT 10
 #define MMU_CMD_TIMEOUT 60000ul //5min timeout for mmu commands (except P0)
@@ -89,7 +85,7 @@ int8_t MMU2::state = 0;
 volatile int8_t MMU2::finda = 1;
 volatile bool MMU2::findaRunoutValid;
 int16_t MMU2::version = -1, MMU2::buildnr = -1;
-millis_t MMU2::next_request, MMU2::next_response;
+millis_t MMU2::last_request, MMU2::next_P0_request;
 char MMU2::rx_buffer[16], MMU2::tx_buffer[16];
 
 #if HAS_LCD_MENU && ENABLED(MMU2_MENUS)
@@ -109,7 +105,8 @@ MMU2::MMU2() {
 }
 
 void MMU2::init() {
-  findaRunoutValid = false;
+
+  set_runout_valid(false);
 
   #if PIN_EXISTS(MMU2_RST)
     // TODO use macros for this
@@ -321,7 +318,7 @@ void MMU2::mmuLoop() {
         last_cmd = cmd;
         cmd = MMU_CMD_NONE;
       }
-      else if (ELAPSED(millis(), next_response)) {
+      else if (ELAPSED(millis(), next_P0_request)) {
         // read FINDA
         tx_str_P(PSTR("P0\n"));
         state = 2; // wait for response
@@ -350,7 +347,7 @@ void MMU2::mmuLoop() {
 
         if (!finda && findaRunoutValid) filamentRunout();
       }
-      else if (ELAPSED(millis(), next_request)) // Resend request after timeout (30s)
+      else if (ELAPSED(millis(), last_request + MMU_P0_TIMEOUT)) // Resend request after timeout (30s)
         state = 1;
 
       break;
@@ -365,7 +362,7 @@ void MMU2::mmuLoop() {
         state = 1;
         last_cmd = MMU_CMD_NONE;
       }
-      else if (ELAPSED(millis(), next_request)) {
+      else if (ELAPSED(millis(), last_request + MMU_CMD_TIMEOUT)) {
         // resend request after timeout
         if (last_cmd) {
           #if ENABLED(MMU2_DEBUG)
@@ -388,7 +385,7 @@ void MMU2::mmuLoop() {
 bool MMU2::rx_start() {
   // check for start message
   if (rx_str_P(PSTR("start\n"))) {
-    next_response = millis() + 300;
+    next_P0_request = millis() + 300;
     return true;
   }
   return false;
@@ -439,7 +436,7 @@ void MMU2::tx_str_P(const char* str) {
   uint8_t len = strlen_P(str);
   for (uint8_t i = 0; i < len; i++) mmuSerial.write(pgm_read_byte(str++));
   rx_buffer[0] = '\0';
-  next_request = millis() + MMU_P0_TIMEOUT;
+  last_request = millis();
 }
 
 
@@ -451,7 +448,7 @@ void MMU2::tx_printf_P(const char* format, int argument = -1) {
   uint8_t len = sprintf_P(tx_buffer, format, argument);
   for (uint8_t i = 0; i < len; i++) mmuSerial.write(tx_buffer[i]);
   rx_buffer[0] = '\0';
-  next_request = millis() + MMU_P0_TIMEOUT;
+  last_request = millis();
 }
 
 
@@ -463,7 +460,7 @@ void MMU2::tx_printf_P(const char* format, int argument1, int argument2) {
   uint8_t len = sprintf_P(tx_buffer, format, argument1, argument2);
   for (uint8_t i = 0; i < len; i++) mmuSerial.write(tx_buffer[i]);
   rx_buffer[0] = '\0';
-  next_request = millis() + MMU_P0_TIMEOUT;
+  last_request = millis();
 }
 
 
@@ -481,7 +478,7 @@ void MMU2::clear_rx_buffer() {
  */
 bool MMU2::rx_ok() {
   if (rx_str_P(PSTR("ok\n"))) {
-    next_response = millis() + 300;
+    next_P0_request = millis() + 300;
     return true;
   }
   return false;
@@ -508,7 +505,7 @@ void MMU2::toolChange(uint8_t index) {
 
   if (!enabled) return;
 
-  findaRunoutValid = false;
+  set_runout_valid(false);
 
   if (index != extruder) {
 
@@ -534,7 +531,7 @@ void MMU2::toolChange(uint8_t index) {
     KEEPALIVE_STATE(NOT_BUSY);
   }
 
-  findaRunoutValid = true;
+  set_runout_valid(true);
 }
 
 
@@ -553,7 +550,7 @@ void MMU2::toolChange(const char* special) {
 
   #if ENABLED(MMU2_MENUS)
 
-    findaRunoutValid = false;
+    set_runout_valid(false);
     KEEPALIVE_STATE(IN_HANDLER);
 
     switch(*special) {
@@ -585,7 +582,7 @@ void MMU2::toolChange(const char* special) {
 
     KEEPALIVE_STATE(NOT_BUSY);
 
-    findaRunoutValid = true;
+    set_runout_valid(true);
 
   #endif
 }
@@ -806,7 +803,8 @@ void MMU2::filamentRunout() {
 
     // no active tool
     extruder = MMU2_NO_TOOL;
-    findaRunoutValid = false;
+
+    set_runout_valid(false);
 
     BUZZ(200, 404);
 
@@ -845,7 +843,8 @@ void MMU2::filamentRunout() {
 
     // no active tool
     extruder = MMU2_NO_TOOL;
-    findaRunoutValid = false;
+
+    set_runout_valid(false);
 
     KEEPALIVE_STATE(NOT_BUSY);
 
diff --git a/Marlin/src/feature/prusa_MMU2/mmu2.h b/Marlin/src/feature/prusa_MMU2/mmu2.h
index 7d7a4facf..88f0ac047 100644
--- a/Marlin/src/feature/prusa_MMU2/mmu2.h
+++ b/Marlin/src/feature/prusa_MMU2/mmu2.h
@@ -24,6 +24,10 @@
 
 #include "../../inc/MarlinConfig.h"
 
+#if ENABLED(FILAMENT_RUNOUT_SENSOR)
+  #include "../runout.h"
+#endif
+
 struct E_Step;
 
 class MMU2 {
@@ -75,8 +79,16 @@ private:
   static volatile int8_t finda;
   static volatile bool findaRunoutValid;
   static int16_t version, buildnr;
-  static millis_t next_request, next_response;
+  static millis_t last_request, next_P0_request;
   static char rx_buffer[16], tx_buffer[16];
+
+  static inline void set_runout_valid(const bool valid) {
+    findaRunoutValid = valid;
+    #if ENABLED(FILAMENT_RUNOUT_SENSOR)
+      if (valid) runout.reset();
+    #endif
+  }
+
 };
 
 extern MMU2 mmu2;