From ce44773caa26d6364c60895ae7bd3c770450d63d Mon Sep 17 00:00:00 2001
From: Lior Halphon <LIJI32@gmail.com>
Date: Fri, 26 Feb 2021 16:40:35 +0200
Subject: [PATCH] Make the printer not deadlock after a sudden termination

---
 Core/printer.c | 10 +++++++---
 Core/printer.h |  3 +--
 Core/timing.c  |  3 +++
 3 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/Core/printer.c b/Core/printer.c
index f04e54d..c8514b4 100644
--- a/Core/printer.c
+++ b/Core/printer.c
@@ -11,7 +11,6 @@
 
 static void handle_command(GB_gameboy_t *gb)
 {
-    
     switch (gb->printer.command_id) {
         case GB_PRINTER_INIT_COMMAND:
             gb->printer.status = 0;
@@ -71,7 +70,7 @@ static void handle_command(GB_gameboy_t *gb)
 }
 
 
-static void byte_reieve_completed(GB_gameboy_t *gb, uint8_t byte_received)
+static void byte_recieve_completed(GB_gameboy_t *gb, uint8_t byte_received)
 {
     gb->printer.byte_to_send = 0;
     switch (gb->printer.command_state) {
@@ -189,11 +188,16 @@ static void byte_reieve_completed(GB_gameboy_t *gb, uint8_t byte_received)
 
 static void serial_start(GB_gameboy_t *gb, bool bit_received)
 {
+    if (gb->printer.idle_time > GB_get_unmultiplied_clock_rate(gb)) {
+        gb->printer.command_state = GB_PRINTER_COMMAND_MAGIC1;
+        gb->printer.bits_received = 0;
+    }
+    gb->printer.idle_time = 0;
     gb->printer.byte_being_received <<= 1;
     gb->printer.byte_being_received |= bit_received;
     gb->printer.bits_received++;
     if (gb->printer.bits_received == 8) {
-        byte_reieve_completed(gb, gb->printer.byte_being_received);
+        byte_recieve_completed(gb, gb->printer.byte_being_received);
         gb->printer.bits_received = 0;
         gb->printer.byte_being_received = 0;
     }
diff --git a/Core/printer.h b/Core/printer.h
index b29650f..f5c9b27 100644
--- a/Core/printer.h
+++ b/Core/printer.h
@@ -48,8 +48,7 @@ typedef struct
     uint8_t image[160 * 200];
     uint16_t image_offset;
     
-    /* TODO: Delete me. */
-    uint64_t padding;
+    uint64_t idle_time;
     
     uint8_t compression_run_lenth;
     bool compression_run_is_compressed;
diff --git a/Core/timing.c b/Core/timing.c
index 655629c..dedc5a0 100644
--- a/Core/timing.c
+++ b/Core/timing.c
@@ -198,6 +198,9 @@ main:
 
 static void advance_serial(GB_gameboy_t *gb, uint8_t cycles)
 {
+    if (gb->printer.command_state || gb->printer.bits_received) {
+        gb->printer.idle_time += cycles;
+    }
     if (gb->serial_length == 0) {
         gb->serial_cycles += cycles;
         return;