diff options
| author | Radomir Dopieralski <openstack@sheep.art.pl> | 2020-07-08 19:59:53 +0200 |
|---|---|---|
| committer | Radomir Dopieralski <openstack@sheep.art.pl> | 2020-07-08 19:59:53 +0200 |
| commit | 83a27edd20de293927e8070da8585b11cb2f8ef7 (patch) | |
| tree | 7c577a7f4ef1edeacabc8ff0768c88bc5fbb245d | |
| parent | 9b4b655b031c82dd319803ecf66bd0994edc200e (diff) | |
SAMD: make the brownout detection level configurable per board
Not all boards have external flash or other components that make them
require 2.7V -- sometimes we can get considerably longer battery life
by decreasing this requirement.
In particular, pewpew10 and pewpew_m4 are powered directly from
battery, with no LDO, and should work fine down to 1.6V.
| -rw-r--r-- | ports/atmel-samd/boards/pewpew10/mpconfigboard.h | 2 | ||||
| -rw-r--r-- | ports/atmel-samd/boards/pewpew_m4/mpconfigboard.h | 3 | ||||
| -rw-r--r-- | ports/atmel-samd/mpconfigport.h | 10 | ||||
| -rw-r--r-- | ports/atmel-samd/supervisor/port.c | 6 |
4 files changed, 18 insertions, 3 deletions
diff --git a/ports/atmel-samd/boards/pewpew10/mpconfigboard.h b/ports/atmel-samd/boards/pewpew10/mpconfigboard.h index 6b3b4aa15..940e250b4 100644 --- a/ports/atmel-samd/boards/pewpew10/mpconfigboard.h +++ b/ports/atmel-samd/boards/pewpew10/mpconfigboard.h @@ -43,3 +43,5 @@ #define DEFAULT_UART_BUS_RX (&pin_PA01) #define DEFAULT_UART_BUS_TX (&pin_PA00) + +#define BOARD_BROWNOUT_LEVEL (6) diff --git a/ports/atmel-samd/boards/pewpew_m4/mpconfigboard.h b/ports/atmel-samd/boards/pewpew_m4/mpconfigboard.h index 60cd8d754..7da5cf14c 100644 --- a/ports/atmel-samd/boards/pewpew_m4/mpconfigboard.h +++ b/ports/atmel-samd/boards/pewpew_m4/mpconfigboard.h @@ -40,3 +40,6 @@ #define IGNORE_PIN_PB09 1 #define IGNORE_PIN_PB10 1 #define IGNORE_PIN_PB11 1 + +#define BOARD_BROWNOUT_LEVEL (6) +// 1.6V diff --git a/ports/atmel-samd/mpconfigport.h b/ports/atmel-samd/mpconfigport.h index 354097ce4..3a5d4e1a2 100644 --- a/ports/atmel-samd/mpconfigport.h +++ b/ports/atmel-samd/mpconfigport.h @@ -112,6 +112,11 @@ #define CIRCUITPY_DEFAULT_STACK_SIZE 4096 #endif +#ifndef BOARD_BROWNOUT_LEVEL ( +#define BOARD_BROWNLOUT_LEVEL (39) +// 2.77V with hysteresis off. Table 37.20 in datasheet. +#endif + // Smallest unit of flash that can be erased. #define FLASH_ERASE_SIZE NVMCTRL_ROW_SIZE @@ -129,6 +134,11 @@ #define CIRCUITPY_DEFAULT_STACK_SIZE (24*1024) #endif +#ifndef BOARD_BROWNOUT_LEVEL ( +#define BOARD_BROWNLOUT_LEVEL (200) +// 2.7V: 1.5V + LEVEL * 6mV. +#endif + // Smallest unit of flash that can be erased. #define FLASH_ERASE_SIZE NVMCTRL_BLOCK_SIZE diff --git a/ports/atmel-samd/supervisor/port.c b/ports/atmel-samd/supervisor/port.c index e892e6cde..5b085dc81 100644 --- a/ports/atmel-samd/supervisor/port.c +++ b/ports/atmel-samd/supervisor/port.c @@ -206,11 +206,11 @@ static void rtc_init(void) { safe_mode_t port_init(void) { #if defined(SAMD21) - // Set brownout detection to ~2.7V. Default from factory is 1.7V, + // Set brownout detection. Default from factory is 1.7V, // which is too low for proper operation of external SPI flash chips (they are 2.7-3.6V). // Disable while changing level. SYSCTRL->BOD33.bit.ENABLE = 0; - SYSCTRL->BOD33.bit.LEVEL = 39; // 2.77V with hysteresis off. Table 37.20 in datasheet. + SYSCTRL->BOD33.bit.LEVEL = BOARD_BROWNOUT_LEVEL; SYSCTRL->BOD33.bit.ENABLE = 1; #ifdef ENABLE_MICRO_TRACE_BUFFER @@ -229,7 +229,7 @@ safe_mode_t port_init(void) { // which is too low for proper operation of external SPI flash chips (they are 2.7-3.6V). // Disable while changing level. SUPC->BOD33.bit.ENABLE = 0; - SUPC->BOD33.bit.LEVEL = 200; // 2.7V: 1.5V + LEVEL * 6mV. + SUPC->BOD33.bit.LEVEL = BOARD_BROWNOUT_LEVEL; SUPC->BOD33.bit.ENABLE = 1; // MPU (Memory Protection Unit) setup. |