From 885c7746b3fff3f10acef55505ce3b17d1b0235f Mon Sep 17 00:00:00 2001
From: sigil-03 <sigil@glyphs.tech>
Date: Fri, 12 Sep 2025 16:19:26 -0600
Subject: [PATCH] deep sleep with PDDS is working

---
 ch32v-insert-coin/src/main.rs | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/ch32v-insert-coin/src/main.rs b/ch32v-insert-coin/src/main.rs
index 6d22219..2db5988 100644
--- a/ch32v-insert-coin/src/main.rs
+++ b/ch32v-insert-coin/src/main.rs
@@ -109,6 +109,15 @@ unsafe fn enter_standby(pin: usize) {
             w.set_sleeponexit(false);
         });
 
+        // set PDDS=1:
+        // get current value of PWR_CTLR
+        let mut reg: u32 = 0x4000_7000;
+        let mut val: u32 = 0;
+        unsafe { val = (reg as *mut u32).read_volatile(); }
+        // modify PDDS
+        val |= 1 << 1; // PWR_CTLR[1] -> PDDS
+        unsafe { (reg as *mut u32).write_volatile(val); }
+
         // // disable all exti interrupts
         let exti = &hal::pac::EXTI;
         // exti.intenr().write(| w| {
@@ -144,8 +153,8 @@ unsafe fn enter_standby(pin: usize) {
 }
 
 unsafe fn init_gpio_irq(pin: u8, port: u8, rising: bool, falling: bool) {
-    critical_section::with(|_| {
-    #[cfg(features="enable_print")]
+    critical_section::with(|_| {    
+    #[cfg(feature="enable_print")]
     println!("init_gpio_irq");
     let exti = &hal::pac::EXTI;
     let afio = &hal::pac::AFIO;