fixed logic bug in Caterina that could stop the bootloader from entering self-programming mode

1 files changed, 18 insertions, 14 deletions

diff --git a/bootloaders/caterina/Caterina.c b/bootloaders/caterina/Caterina.c
index 0cb9590..abcba2b 100755
--- a/bootloaders/caterina/Caterina.c
+++ b/bootloaders/caterina/Caterina.c
@@ -66,7 +66,7 @@ uint16_t RxLEDPulse = 0; // time remaining for Rx LED pulse
 uint16_t Timeout = 0;

 

 uint16_t bootKey = 0x7777;

-volatile uint16_t *const bootKeyPtr = (volatile uint16_t *)0x0A00;

+volatile uint16_t *const bootKeyPtr = (volatile uint16_t *)0x0800;

 

 void StartSketch(void)

 {

@@ -106,25 +106,29 @@ void LEDPulse(void)
 }

 

 /** Main program entry point. This routine configures the hardware required by the bootloader, then continuously

- *  runs the bootloader processing routine until instructed to soft-exit, or hard-reset via the watchdog to start

- *  the loaded application code.

+ *  runs the bootloader processing routine until it times out or is instructed to exit.

  */

 int main(void)

 {

-	/* Watchdog may be configured with a 15 ms period so must disable it before doing anything else */

-	wdt_disable();

-	

-	/* Check the reason for the reset and act accordingly */

+	/* Save the value of the boot key memory before it is overwritten */

+	uint16_t bootKeyPtrVal = *bootKeyPtr;

+	*bootKeyPtr = 0;

+

+	/* Check the reason for the reset so we can act accordingly */

 	uint8_t  mcusr_state = MCUSR;		// store the initial state of the Status register

 	MCUSR = 0;							// clear all reset flags	

-	// After a power-on reset skip the bootloader and jump straight to sketch 

-	// if one exists.

-	if (mcusr_state & (1<<PORF) && pgm_read_word(0) != 0xFFFF) {		

+

+	/* Watchdog may be configured with a 15 ms period so must disable it before going any further */

+	wdt_disable();

+	

+	if (mcusr_state & (1<<EXTRF)) {

+		// External reset -  we should continue to self-programming mode.

+	} else if (mcusr_state == (1<<PORF) && pgm_read_word(0) != 0xFFFF) {		

+		// After a power-on reset skip the bootloader and jump straight to sketch 

+		// if one exists.	

 		StartSketch();

-	}

-	uint16_t bootKeyPtrVal = *bootKeyPtr;

-	*bootKeyPtr = 0;

-	if ((mcusr_state & (1<<WDRF)) && (bootKeyPtrVal != bootKey) && (pgm_read_word(0) != 0xFFFF)) {	

+	} else if ((mcusr_state == (1<<WDRF)) && (bootKeyPtrVal != bootKey) && (pgm_read_word(0) != 0xFFFF)) {	

+		// If it looks like an "accidental" watchdog reset then start the sketch.

 		StartSketch();

 	}