Added support for Code ROM persistence.

This isn't something exceptionally useful as normally the emulator is started
with "flashing" a game into it, but it is notably required for the currently
existing bootloader versions to operate correctly (they don't try to reflash
the game if they remeber it being loaded in the EEPROM by checksum).

.gitignore

@@ -16,6 +16,7 @@
 /gamefile.c
 # If the program created various files, ignore those too
 /eeprom.bin
+/coderom.bin
 /capture.mp4
 # If for a Windows build an SDL2 development library is supplied locally, skip that
 /SDL2*

Make_config.mk

@@ -62,7 +62,7 @@ CC_LIB=
 #
 # Version number to use. It should be a BCD date of YYYYMMDD format.
 #
-VER_DATE=0x20170918
+VER_DATE=0x20170919
 #
 #
 # In case a test build (debug) is necessary, give 'test' here. It enables

Makefile

@@ -54,6 +54,7 @@ OBJECTS += $(OBD)/cu_spisd.o
 OBJECTS += $(OBD)/filesys.o
 endif
 OBJECTS += $(OBD)/eepdump.o
+OBJECTS += $(OBD)/romdump.o
 OBJECTS += $(OBD)/guicore.o
 OBJECTS += $(OBD)/audio.o
 OBJECTS += $(OBD)/ginput.o
@@ -176,6 +177,9 @@ $(OBD)/frame.o: frame.c $(DEPS)
 $(OBD)/eepdump.o: eepdump.c $(DEPS)
 	$(CC) -c $< -o $@ $(CFSIZ)
 
+$(OBD)/romdump.o: romdump.c $(DEPS)
+	$(CC) -c $< -o $@ $(CFSIZ)
+
 $(OBD)/avconv.o: avconv.c $(DEPS)
 	$(CC) -c $< -o $@ $(CFSIZ)
 

cu_avr.c

@@ -104,9 +104,12 @@ boole           event_it_enter;
 /* Vector to call when entering interrupt */
 auint           event_it_vect;
 
-/* EEPROM change indicator */
+/* EEPROM change indicator for saves to persistent storage */
 boole           eeprom_changed;
 
+/* Code ROM change indicator for saves to persistent storage */
+boole           crom_changed;
+
 /* Watchdog-based debug counter: Time of last WDR execution */
 auint           wd_last;
 
@@ -916,11 +919,15 @@ static auint cu_avr_read_io(auint port)
 /*
 ** Resets the CPU as if it was power-cycled. It properly initializes
 ** everything from the state as if cu_avr_crom_update() and cu_avr_io_update()
-** was called.
+** was called. The bootpri flag requests prioritizing the bootloader when set
+** TRUE, otherwise game is prioritized (used when both a game and a bootloader
+** appears to be present in the ROM).
 */
-void  cu_avr_reset(void)
+void  cu_avr_reset(boole bootpri)
 {
  auint i;
+ boole hasgame;
+ boole hasboot;
 
  for (i = 0U; i < 4096U; i++){
   access_mem[i] = 0U;
@@ -947,12 +954,16 @@ void  cu_avr_reset(void)
 
  cpu_state.latch = 0U;
 
- /* Check whether something is loaded. Normally the AVR is fused to use the
- ** boot loader, so if anything is present there, use that. If there is no
- ** boot loader (only an application is loaded), boot that instead. */
+ /* Determine boot fuses according to the contents of the ROM and the boot
+ ** prioritization parameter. The boot loader is used when it exists and it
+ ** is prioritized or when it looks like there is no game in the Code ROM. */
 
- if ( (cpu_state.crom[(VBASE_BOOT * 2U) + 0U] != 0U) ||
-      (cpu_state.crom[(VBASE_BOOT * 2U) + 1U] != 0U) ){ cpu_state.iors[CU_IO_MCUCR] |= 2U; }
+ hasgame = (cpu_state.crom[                    0U] != 0U) ||
+           (cpu_state.crom[                    1U] != 0U);
+ hasboot = (cpu_state.crom[(VBASE_BOOT * 2U) + 0U] != 0U) ||
+           (cpu_state.crom[(VBASE_BOOT * 2U) + 1U] != 0U);
+ if ( (hasboot && bootpri) ||
+      (!hasgame) ){ cpu_state.iors[CU_IO_MCUCR] |= 2U; }
 
  cpu_state.pc = (((cpu_state.iors[CU_IO_MCUCR] >> 1) & 1U) * VBASE_BOOT) + VECT_RESET;
 
@@ -1116,7 +1127,8 @@ uint8* cu_avr_get_ioinfo(void)
 /*
 ** Returns whether the EEPROM changed since the last clear of this indicator.
 ** Calling cu_avr_io_update() clears this indicator (as well as resetting by
-** cu_avr_reset()). Passing TRUE also clears it.
+** cu_avr_reset()). Passing TRUE also clears it. This can be used to save
+** EEPROM state to persistent storage when it changes.
 */
 boole cu_avr_eeprom_ischanged(boole clear)
 {
@@ -1126,6 +1138,20 @@ boole cu_avr_eeprom_ischanged(boole clear)
 }
 
 
+/*
+** Returns whether the Code ROM changed since the last clear of this
+** indicator. Calling cu_avr_io_update() clears this indicator (as well as
+** resetting by cu_avr_reset()). Passing TRUE also clears it. This can be used
+** to save Code ROM state to persistent storage when it changes.
+*/
+boole cu_avr_crom_ischanged(boole clear)
+{
+ boole ret = crom_changed;
+ if (clear){ crom_changed = FALSE; }
+ return ret;
+}
+
+
 
 /*
 ** Returns whether the Code ROM was modified since reset. This can be used to
@@ -1179,6 +1205,7 @@ void  cu_avr_crom_update(auint base, auint len)
  }
 
  cpu_state.crom_mod = TRUE;
+ crom_changed = TRUE;
 }
 
 
@@ -1194,6 +1221,7 @@ void  cu_avr_io_update(void)
  auint t0;
 
  eeprom_changed = FALSE;
+ crom_changed   = FALSE;
 
  t0    = (cpu_state.iors[CU_IO_TCNT1H] << 8) |
          (cpu_state.iors[CU_IO_TCNT1L]     );

cu_avr.h

@@ -38,9 +38,11 @@
 /*
 ** Resets the CPU as if it was power-cycled. It properly initializes
 ** everything from the state as if cu_avr_crom_update() and cu_avr_io_update()
-** was called.
+** was called. The bootpri flag requests prioritizing the bootloader when set
+** TRUE, otherwise game is prioritized (used when both a game and a bootloader
+** appears to be present in the ROM).
 */
-void  cu_avr_reset(void);
+void  cu_avr_reset(boole bootpri);
 
 
 /*
@@ -92,11 +94,21 @@ uint8* cu_avr_get_ioinfo(void);
 /*
 ** Returns whether the EEPROM changed since the last clear of this indicator.
 ** Calling cu_avr_io_update() clears this indicator (as well as resetting by
-** cu_avr_reset()). Passing TRUE also clears it.
+** cu_avr_reset()). Passing TRUE also clears it. This can be used to save
+** EEPROM state to persistent storage when it changes.
 */
 boole cu_avr_eeprom_ischanged(boole clear);
 
 
+/*
+** Returns whether the Code ROM changed since the last clear of this
+** indicator. Calling cu_avr_io_update() clears this indicator (as well as
+** resetting by cu_avr_reset()). Passing TRUE also clears it. This can be used
+** to save Code ROM state to persistent storage when it changes.
+*/
+boole cu_avr_crom_ischanged(boole clear);
+
+
 /*
 ** Returns whether the Code ROM was modified since reset. This can be used to
 ** determine if it is necessary to include the Code ROM in a save state.

cu_avr_e.h

@@ -450,7 +450,6 @@ static void op_17(auint arg1, auint arg2) /* SPM */
         (WRAP32(cpu_state.spm_end - cpu_state.cycle)) ){
     cycle_next_event = cpu_state.spm_end; /* Set SPM HW processing target */
    }
-   cpu_state.crom_mod = TRUE;             /* Code ROM modified */
   }else if (cpu_state.spm_mode == 0x08U){ /* Boot lock bit set (unimplemented) */
    cpu_state.iors[CU_IO_SPMCSR] &= 0xE0U;
   }else if (cpu_state.spm_mode == 0x10U){ /* RWW section read enable */

cu_avr_n.h

@@ -222,7 +222,6 @@ static void cu_avr_exec(void)
           (WRAP32(cpu_state.spm_end - cpu_state.cycle)) ){
       cycle_next_event = cpu_state.spm_end; /* Set SPM HW processing target */
      }
-     cpu_state.crom_mod = TRUE;             /* Code ROM modified */
     }else if (cpu_state.spm_mode == 0x08U){ /* Boot lock bit set (unimplemented) */
      cpu_state.iors[CU_IO_SPMCSR] &= 0xE0U;
     }else if (cpu_state.spm_mode == 0x10U){ /* RWW section read enable */

cu_hfile.c

@@ -1,7 +1,7 @@
 /*
  *  Hex file parser
  *
- *  Copyright (C) 2016
+ *  Copyright (C) 2016 - 2017
  *    Sandor Zsuga (Jubatian)
  *  Uzem (the base of CUzeBox) is copyright (C)
  *    David Etherton,
@@ -41,7 +41,8 @@ static const char cu_war[] = "Warning: ";
 
 /*
 ** Attempts to load the passed file into code memory. The code memory is not
-** cleared, so bootloader image may be added before this if there is any.
+** cleared, so bootloader image or other contents may be added before this if
+** there are any.
 **
 ** The code memory must be 64 KBytes.
 **

cu_hfile.h

@@ -1,7 +1,7 @@
 /*
  *  Hex file parser
  *
- *  Copyright (C) 2016
+ *  Copyright (C) 2016 - 2017
  *    Sandor Zsuga (Jubatian)
  *  Uzem (the base of CUzeBox) is copyright (C)
  *    David Etherton,
@@ -38,7 +38,8 @@
 
 /*
 ** Attempts to load the passed file into code memory. The code memory is not
-** cleared, so bootloader image may be added before this if there is any.
+** cleared, so bootloader image or other contents may be added before this if
+** there are any.
 **
 ** The code memory must be 64 KBytes.
 **

cu_ufile.c

@@ -1,7 +1,7 @@
 /*
  *  UzeRom file parser
  *
- *  Copyright (C) 2016
+ *  Copyright (C) 2016 - 2017
  *    Sandor Zsuga (Jubatian)
  *  Uzem (the base of CUzeBox) is copyright (C)
  *    David Etherton,
@@ -46,7 +46,8 @@ static const char cu_war[] = "Warning: ";
 
 /*
 ** Attempts to load the passed file into code memory. The code memory is not
-** cleared, so bootloader image may be added before this if there is any.
+** cleared, so bootloader image or other contents may be added before this if
+** there are any.
 **
 ** The code memory must be 64 KBytes.
 **

cu_ufile.h

@@ -1,7 +1,7 @@
 /*
  *  UzeRom file parser
  *
- *  Copyright (C) 2016
+ *  Copyright (C) 2016 - 2017
  *    Sandor Zsuga (Jubatian)
  *  Uzem (the base of CUzeBox) is copyright (C)
  *    David Etherton,
@@ -55,7 +55,8 @@ typedef struct{
 
 /*
 ** Attempts to load the passed file into code memory. The code memory is not
-** cleared, so bootloader image may be added before this if there is any.
+** cleared, so bootloader image or other contents may be added before this if
+** there are any.
 **
 ** The code memory must be 64 KBytes.
 **

eepdump.c

@@ -45,16 +45,16 @@ void eepdump_load(uint8* eeprom)
 {
  auint rv;
 
- if (!filesys_open(FILESYS_CH_EEP, eepdump_file)){ goto ex_fail; }
+ if (!filesys_open(FILESYS_CH_ROM, eepdump_file)){ goto ex_fail; }
 
- rv = filesys_read(FILESYS_CH_EEP, eeprom, 2048U);
+ rv = filesys_read(FILESYS_CH_ROM, eeprom, 2048U);
  if (rv != 2048){ goto ex_fail; }
 
- filesys_flush(FILESYS_CH_EEP);
+ filesys_flush(FILESYS_CH_ROM);
  return;
 
 ex_fail:
- filesys_flush(FILESYS_CH_EEP);
+ filesys_flush(FILESYS_CH_ROM);
  memset(eeprom, 0xFFU, 2048U);
  return;
 }
@@ -67,10 +67,10 @@ void eepdump_load(uint8* eeprom)
 */
 void eepdump_save(uint8 const* eeprom)
 {
- (void)(filesys_open(FILESYS_CH_EEP, eepdump_file));   /* Might fail since tries to open for reading */
+ (void)(filesys_open(FILESYS_CH_ROM, eepdump_file));   /* Might fail since tries to open for reading */
 
- (void)(filesys_write(FILESYS_CH_EEP, eeprom, 2048U)); /* Don't care for faults (can't do anything about them) */
+ (void)(filesys_write(FILESYS_CH_ROM, eeprom, 2048U)); /* Don't care for faults (can't do anything about them) */
 
- filesys_flush(FILESYS_CH_EEP);
+ filesys_flush(FILESYS_CH_ROM);
  return;
 }

filesys.h

@@ -1,7 +1,7 @@
 /*
  *  Filesystem interface layer
  *
- *  Copyright (C) 2016
+ *  Copyright (C) 2016 - 2017
  *    Sandor Zsuga (Jubatian)
  *  Uzem (the base of CUzeBox) is copyright (C)
  *    David Etherton,
@@ -52,8 +52,8 @@
 #define FILESYS_CH_SD      0U
 /* Various emulator one-shot tasks (such as game loading) */
 #define FILESYS_CH_EMU     1U
-/* EEPROM dumps */
-#define FILESYS_CH_EEP     2U
+/* EEPROM & Code ROM dumps */
+#define FILESYS_CH_ROM     2U
 
 /* Number of filesystem channels (must be one larger than the largest entry
 ** of the list above) */