Fix 1200 baud reset.

tannewt · tannewt · commit 39f30aeec699 · 2017-12-20T15:17:06.000-08:00
Fixes adafruit#494
diff --git a/atmel-samd/common-hal/microcontroller/__init__.c b/atmel-samd/common-hal/microcontroller/__init__.c
@@ -55,15 +55,14 @@ void common_hal_mcu_enable_interrupts(void) {
 }
 
 extern uint32_t _ezero;
-extern uint32_t _srelocate;
 
 void common_hal_mcu_on_next_reset(mcu_runmode_t runmode) {
     // Set up the defaults.
     _bootloader_dbl_tap = DBL_TAP_MAGIC;
     _ezero = CIRCUITPY_CANARY_WORD;
 
     if (runmode == RUNMODE_BOOTLOADER) {
-        if (&_bootloader_dbl_tap < &_srelocate) {
+        if (!bootloader_available()) {
             mp_raise_ValueError("Cannot reset into bootloader because no bootloader is present.");
         }
         // Pretend to be the first of the two reset presses needed to enter the
diff --git a/atmel-samd/mphalport.c b/atmel-samd/mphalport.c
@@ -62,7 +62,7 @@ volatile bool reset_on_disconnect = false;
 
 void usb_dtr_notify(uint8_t port, bool set) {
     mp_cdc_enabled = set;
-    if (!set && reset_on_disconnect && _bootloader_dbl_tap != 0) {
+    if (!set && reset_on_disconnect && bootloader_available()) {
         reset_to_bootloader();
     }
 }
diff --git a/atmel-samd/reset.c b/atmel-samd/reset.c
@@ -38,3 +38,8 @@ void reset_to_bootloader(void) {
     _bootloader_dbl_tap = DBL_TAP_MAGIC;
     reset();
 }
+
+extern uint32_t _srelocate;
+bool bootloader_available(void) {
+    return &_bootloader_dbl_tap >= &_srelocate;
+}
diff --git a/atmel-samd/reset.h b/atmel-samd/reset.h
@@ -33,5 +33,6 @@ extern uint32_t _bootloader_dbl_tap;
 
 void reset_to_bootloader(void);
 void reset(void);
+bool bootloader_available(void);
 
 #endif  // MICROPY_INCLUDED_ATMEL_SAMD_RESET_H

Original file line number	Diff line number	Diff line change
`@@ -55,15 +55,14 @@ void common_hal_mcu_enable_interrupts(void) {`
`55`	`55`	`}`
`56`	`56`
`57`	`57`	`extern uint32_t _ezero;`
`58`		`-extern uint32_t _srelocate;`
`59`	`58`
`60`	`59`	`void common_hal_mcu_on_next_reset(mcu_runmode_t runmode) {`
`61`	`60`	`// Set up the defaults.`
`62`	`61`	`_bootloader_dbl_tap = DBL_TAP_MAGIC;`
`63`	`62`	`_ezero = CIRCUITPY_CANARY_WORD;`
`64`	`63`
`65`	`64`	`if (runmode == RUNMODE_BOOTLOADER) {`
`66`		`- if (&_bootloader_dbl_tap < &_srelocate) {`
	`65`	`+ if (!bootloader_available()) {`
`67`	`66`	`mp_raise_ValueError("Cannot reset into bootloader because no bootloader is present.");`
`68`	`67`	`}`
`69`	`68`	`// Pretend to be the first of the two reset presses needed to enter the`
Original file line number	Diff line number	Diff line change
`@@ -62,7 +62,7 @@ volatile bool reset_on_disconnect = false;`
`62`	`62`
`63`	`63`	`void usb_dtr_notify(uint8_t port, bool set) {`
`64`	`64`	`mp_cdc_enabled = set;`
`65`		`- if (!set && reset_on_disconnect && _bootloader_dbl_tap != 0) {`
	`65`	`+ if (!set && reset_on_disconnect && bootloader_available()) {`
`66`	`66`	`reset_to_bootloader();`
`67`	`67`	`}`
`68`	`68`	`}`
Original file line number	Diff line number	Diff line change
`@@ -38,3 +38,8 @@ void reset_to_bootloader(void) {`
`38`	`38`	`_bootloader_dbl_tap = DBL_TAP_MAGIC;`
`39`	`39`	`reset();`
`40`	`40`	`}`
	`41`	`+`
	`42`	`+extern uint32_t _srelocate;`
	`43`	`+bool bootloader_available(void) {`
	`44`	`+ return &_bootloader_dbl_tap >= &_srelocate;`
	`45`	`+}`