diff --git a/examples/standby_autowake/README.md b/examples/standby_autowake/README.md
index 70e71b4e6f3b0eca3fa503a13ec204e42025b5df..2fe3d123f79270038312627ab679fc4e3442c57e 100644
--- a/examples/standby_autowake/README.md
+++ b/examples/standby_autowake/README.md
@@ -6,8 +6,7 @@ This example serves to show how to put the CH32V003 into its lowest power state
Power consumption should be around 10uA.
-The MCU only toggles the LED and prints a message, then it goes to sleep.
-The LED staying on demonstrates that GPIO keeps its state even when the rest of the mcu is in a coma.
+Refer to the standby_btn example for GPIO settings.
Based on the groundwork of Marek M.
diff --git a/examples/standby_autowake/standby_autowake.c b/examples/standby_autowake/standby_autowake.c
index 4cfaaf34c1248cd27cac5e82a3cef6d78d754a5e..9e41489a4b595d10fec04f28871180dc49fffa92 100644
--- a/examples/standby_autowake/standby_autowake.c
+++ b/examples/standby_autowake/standby_autowake.c
@@ -3,30 +3,56 @@
#include "ch32v003fun.h"
#include <stdio.h>
-/* somehow this ISR won't get called??
-void AWU_IRQHandler( void ) __attribute__((interrupt));
-void AWU_IRQHandler( void ) {
- GPIOD->OUTDR ^= (1 << 4);
-}
-*/
int main()
{
SystemInit();
- Delay_Ms(100);
- printf("\r\n\r\nlow power example\r\n\r\n");
+ // This delay gives us some time to reprogram the device.
+ // Otherwise if the device enters standby mode we can't
+ // program it any more.
+ Delay_Ms(5000);
- RCC->APB2PCENR |= RCC_APB2Periph_GPIOD;
- // GPIO D4 Push-Pull
- GPIOD->CFGLR &= ~(0xf<<(4*4));
- GPIOD->CFGLR |= (GPIO_Speed_10MHz | GPIO_CNF_OUT_PP)<<(4*4);
- GPIOD->OUTDR |= (1 << 4);
+ printf("\r\n\r\nlow power example\r\n\r\n");
- // give the user time to open the terminal connection
- //Delay_Ms(5000);
- printf("5000ms wait over\r\n");
+ // Set all GPIOs to input pull up
+ RCC->APB2PCENR |= RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOC | RCC_APB2Periph_GPIOD;
+ // GPIOA: Set to output
+ GPIOA->CFGLR = (GPIO_CNF_IN_PUPD<<(4*2)) |
+ (GPIO_CNF_IN_PUPD<<(4*1));
+ GPIOA->BSHR = GPIO_BSHR_BS2 | GPIO_BSHR_BR1;
+ GPIOC->CFGLR = (GPIO_CNF_IN_PUPD<<(4*7)) |
+ (GPIO_CNF_IN_PUPD<<(4*6)) |
+ (GPIO_CNF_IN_PUPD<<(4*5)) |
+ (GPIO_CNF_IN_PUPD<<(4*4)) |
+ (GPIO_CNF_IN_PUPD<<(4*3)) |
+ (GPIO_CNF_IN_PUPD<<(4*2)) |
+ (GPIO_CNF_IN_PUPD<<(4*1)) |
+ (GPIO_CNF_IN_PUPD<<(4*0));
+ GPIOC->BSHR = GPIO_BSHR_BS7 |
+ GPIO_BSHR_BS6 |
+ GPIO_BSHR_BS5 |
+ GPIO_BSHR_BS4 |
+ GPIO_BSHR_BS3 |
+ GPIO_BSHR_BS2 |
+ GPIO_BSHR_BS1 |
+ GPIO_BSHR_BS0;
+ GPIOD->CFGLR = (GPIO_CNF_IN_PUPD<<(4*7)) |
+ (GPIO_CNF_IN_PUPD<<(4*6)) |
+ (GPIO_CNF_IN_PUPD<<(4*5)) |
+ (GPIO_CNF_IN_PUPD<<(4*4)) |
+ (GPIO_CNF_IN_PUPD<<(4*3)) |
+ (GPIO_CNF_IN_PUPD<<(4*2)) |
+ (GPIO_CNF_IN_PUPD<<(4*0));
+ GPIOD->BSHR = GPIO_BSHR_BS7 |
+ GPIO_BSHR_BS6 |
+ GPIO_BSHR_BS5 |
+ GPIO_BSHR_BS4 |
+ GPIO_BSHR_BS3 |
+ GPIO_BSHR_BS2 |
+ GPIO_BSHR_BS0;
+
// enable power interface module clock
RCC->APB1PCENR |= RCC_APB1Periph_PWR;
@@ -62,6 +88,5 @@ int main()
// restore clock to full speed
SystemInit();
printf("\r\nawake, %u\r\n", counter++);
- GPIOD->OUTDR ^= (1 << 4);
}
}
diff --git a/examples/standby_btn/README.md b/examples/standby_btn/README.md
index 794e8b4ccc30b278904c12658a303c200170b380..4b6421c99cef584df8d4a0f91fde4b1418dbe453 100644
--- a/examples/standby_btn/README.md
+++ b/examples/standby_btn/README.md
@@ -1,15 +1,30 @@
# the deepest slumber
+**WARNING: You MUST hard-reboot the CH32V003 to allow it to go into deep sleep. You cannot go from flashing to deep sleep without a hard power cycle.**
+
This example serves to show how to put the CH32V003 into its lowest power state (standby) and have it wake with a button press.
-Power consumption should be around 10uA.
+Power consumption should be around 9uA.
+
+To enter 10uA standby mode you must perform these steps:
+
+1. GPIOs other than the wake up pin can be set to either input or output mode (see notes).
+2. Set GPIO(s) for wake up to input mode with appropriate pull up/down.
+3. Enable AFIO clock and set AFIO_EXTICR to the wakeup channel.
+4. Configure EXTI event.
+5. Set PWR_CTLR_PDDS bit in PWR_CTLR (Setting PWREN in RCC_APB1PCENR is not required hum?)
+6. Set SLEEPDEEP bit in PFIC_SCTLR
+7. Call __WFE() to enter standby mode.
-The MCU only toggles the LED and prints a message, then it goes back to sleep.
-The LED staying on demonstrates that GPIO keeps its state even when the rest of the mcu is in a coma.
+Note:
+* GPIOs in output mode will retain state during standby.
+* GPIO if set to input mode must have internal or external pulling resistor. Floating input pin will cause 100uA standby current.
+* Once CH32V003 enters standby mode, it won't respond to any SWDIO command, therefor cannot be reprogrammed. User must provide a way to have the processor stay awake for reprogramming, e.g. some delay at startup.
+* Debug circuitry will consume power. If minichlink terminal is active (including immediately after flashing), standby current will stay around 1.2mA until power cycle.
Based on the groundwork of Marek M.
## circuit
-Connect LED to PD4 (with resistor), connect button to GND and PD2.
+Connect button to GND and PD2.
There is no debouncing but it should suffice for waking the chip.
diff --git a/examples/standby_btn/standby_btn.c b/examples/standby_btn/standby_btn.c
index 33f55a89cb8c29e7ae7991cb01c0fac41ed183cb..be6c99b7f109db9e04af80dea2d94618a5aac4d8 100644
--- a/examples/standby_btn/standby_btn.c
+++ b/examples/standby_btn/standby_btn.c
@@ -3,40 +3,60 @@
#include "ch32v003fun.h"
#include <stdio.h>
-void EXTI7_0_IRQHandler( void ) __attribute__((interrupt));
-void EXTI7_0_IRQHandler( void ) {
- //GPIOD->OUTDR ^= (1 << 4);
-}
-
-
int main()
{
SystemInit();
- Delay_Ms(100);
+
+ // This delay gives us some time to reprogram the device.
+ // Otherwise if the device enters standby mode we can't
+ // program it any more.
+ Delay_Ms(5000);
printf("\n\nlow power example\n\n");
+ RCC->APB2PCENR |= RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOC | RCC_APB2Periph_GPIOD;
+ // GPIOA: Set to output
+ GPIOA->CFGLR = ((GPIO_CNF_OUT_PP | GPIO_Speed_2MHz)<<(4*2)) |
+ ((GPIO_CNF_OUT_PP | GPIO_Speed_2MHz)<<(4*1));
+ GPIOA->BSHR = GPIO_BSHR_BS2 | GPIO_BSHR_BR1;
+ // GPIOC: Set to input with mixed pull-up / pull-down
+ GPIOC->CFGLR = (GPIO_CNF_IN_PUPD<<(4*7)) |
+ (GPIO_CNF_IN_PUPD<<(4*6)) |
+ (GPIO_CNF_IN_PUPD<<(4*5)) |
+ (GPIO_CNF_IN_PUPD<<(4*4)) |
+ (GPIO_CNF_IN_PUPD<<(4*3)) |
+ (GPIO_CNF_IN_PUPD<<(4*2)) |
+ (GPIO_CNF_IN_PUPD<<(4*1)) |
+ (GPIO_CNF_IN_PUPD<<(4*0));
+ GPIOC->BSHR = GPIO_BSHR_BS7 |
+ GPIO_BSHR_BR6 |
+ GPIO_BSHR_BS5 |
+ GPIO_BSHR_BR4 |
+ GPIO_BSHR_BS3 |
+ GPIO_BSHR_BR2 |
+ GPIO_BSHR_BS1 |
+ GPIO_BSHR_BR0;
+ // GPIOD: D2 set to input pull-up
+ GPIOD->CFGLR = (GPIO_CNF_IN_PUPD<<(4*7)) |
+ (GPIO_CNF_IN_PUPD<<(4*6)) |
+ (GPIO_CNF_IN_PUPD<<(4*5)) |
+ (GPIO_CNF_IN_PUPD<<(4*4)) |
+ (GPIO_CNF_IN_PUPD<<(4*3)) |
+ (GPIO_CNF_IN_PUPD<<(4*2)) |
+ (GPIO_CNF_IN_PUPD<<(4*0));
+ GPIOD->BSHR = GPIO_BSHR_BR7 |
+ GPIO_BSHR_BS6 |
+ GPIO_BSHR_BR5 |
+ GPIO_BSHR_BS4 |
+ GPIO_BSHR_BR3 |
+ GPIO_BSHR_BS2 |
+ GPIO_BSHR_BR0;
- RCC->APB2PCENR |= RCC_APB2Periph_GPIOD;
- // GPIO D4 Push-Pull
- GPIOD->CFGLR &= ~(0xf<<(4*4));
- GPIOD->CFGLR |= (GPIO_Speed_10MHz | GPIO_CNF_OUT_PP)<<(4*4);
- GPIOD->OUTDR |= (1 << 4);
-
- // give the user time to open the terminal connection
- //Delay_Ms(5000);
- //printf("5000ms wait over\r\n");
-
- // enable alternate IO function module clock
+ // AFIO is needed for EXTI
RCC->APB2PCENR |= RCC_AFIOEN;
- // configure button on PD2 as input, pullup
- GPIOD->CFGLR &= ~(0xf<<(2*4));
- GPIOD->CFGLR |= (GPIO_CNF_IN_PUPD)<<(2*4);
- GPIOD->BSHR = (1 << 2);
-
// assign pin 2 interrupt from portD (0b11) to EXTI channel 2
- AFIO->EXTICR |= (uint32_t)(0b11 << (2 * 2));
+ AFIO->EXTICR |= (uint32_t)(0b11 << (2*2));
// enable line2 interrupt event
EXTI->EVENR |= EXTI_Line2;
@@ -56,6 +76,6 @@ int main()
// restore clock to full speed
SystemInit();
printf("\nawake, %u\n", counter++);
- GPIOD->OUTDR ^= (1 << 4);
+ Delay_Ms(5000); // wake and reflash can happen here
}
}