diff options
| author | iabdalkader <i.abdalkader@gmail.com> | 2022-04-07 16:29:44 +0200 |
|---|---|---|
| committer | Damien George <damien@micropython.org> | 2022-04-11 16:00:40 +1000 |
| commit | 2a19c3cfe15506b3b51b9a5435db984f64299df0 (patch) | |
| tree | b2aeaa69e4978c521e5ed0df87c6e7eb6d94943e | |
| parent | cb0372b5bfe72fee99f5b3ffb94dcd1735353f4b (diff) | |
stm32/sdram: Add function to enable SDRAM power-down mode.
Add power-down mode for maximum power saving while in standby mode, to be
used by a board if needed. Also fix a typo in a comment.
| -rw-r--r-- | ports/stm32/sdram.c | 10 | ||||
| -rw-r--r-- | ports/stm32/sdram.h | 1 |
2 files changed, 10 insertions, 1 deletions
diff --git a/ports/stm32/sdram.c b/ports/stm32/sdram.c index 4615c4fe1..4ca79f270 100644 --- a/ports/stm32/sdram.c +++ b/ports/stm32/sdram.c @@ -259,7 +259,7 @@ static void sdram_init_seq(SDRAM_HandleTypeDef void sdram_enter_low_power(void) { // Enter self-refresh mode. - // In self-refresh mode the SDRAM retains data with external clocking. + // In self-refresh mode the SDRAM retains data without external clocking. FMC_SDRAM_DEVICE->SDCMR |= (FMC_SDRAM_CMD_SELFREFRESH_MODE | // Command Mode FMC_SDRAM_CMD_TARGET_BANK | // Command Target (0 << 5U) | // Auto Refresh Number -1 @@ -276,6 +276,14 @@ void sdram_leave_low_power(void) { (0 << 9U)); // Mode Register Definition } +void sdram_enter_power_down(void) { + // Enter power-down mode. + FMC_SDRAM_DEVICE->SDCMR |= (FMC_SDRAM_CMD_POWERDOWN_MODE | // Command Mode + FMC_SDRAM_CMD_TARGET_BANK | // Command Target + (0 << 5U) | // Auto Refresh Number -1 + (0 << 9U)); // Mode Register Definition +} + #if __GNUC__ >= 11 // Prevent array bounds warnings when accessing SDRAM_START_ADDRESS as a memory pointer. #pragma GCC diagnostic push diff --git a/ports/stm32/sdram.h b/ports/stm32/sdram.h index f7a124add..5d170ea0d 100644 --- a/ports/stm32/sdram.h +++ b/ports/stm32/sdram.h @@ -13,5 +13,6 @@ void *sdram_start(void); void *sdram_end(void); void sdram_enter_low_power(void); void sdram_leave_low_power(void); +void sdram_enter_power_down(void); bool sdram_test(bool exhaustive); #endif // __SDRAM_H__ |