From e8378e832ab736320e9b54dae324519e2a59ddeb Mon Sep 17 00:00:00 2001
From: Kizarm <mrazik@volny.cz>
Date: Fri, 18 Oct 2024 14:32:41 +0200
Subject: [PATCH] set system clock to 144MHz

---
 V203/usb/ch32v203/system.cpp | 15 ++++++---------
 V203/usb/ch32v203/system.h   |  2 +-
 2 files changed, 7 insertions(+), 10 deletions(-)

diff --git a/V203/usb/ch32v203/system.cpp b/V203/usb/ch32v203/system.cpp
index d94ffbe..68818bd 100644
--- a/V203/usb/ch32v203/system.cpp
+++ b/V203/usb/ch32v203/system.cpp
@@ -10,14 +10,13 @@ enum CLKSRC : uint32_t {
 static constexpr unsigned HSI_VALUE             = 8000000u;       /* Value of the Internal oscillator in Hz */
 static constexpr unsigned HSE_VALUE             = 8000000u;       /* Value of the External oscillator in Hz */
 /* In the following line adjust the External High Speed oscillator (HSE) Startup Timeout value */
-static constexpr unsigned SYSCLK_FREQ_96MHz_HSE = SYSTEM_CORE_CLOCK;
 static constexpr unsigned HSE_STARTUP_TIMEOUT   = 0x1000u;        /* Time out for HSE start up */
 // HSE i HSI mají frekvenci 8 MHz
 static constexpr uint8_t AHBPrescTable[16] = {0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 6, 7, 8, 9};
 
-uint32_t SystemCoreClock = SYSCLK_FREQ_96MHz_HSE;                 /* System Clock Frequency (Core Clock) */
+uint32_t SystemCoreClock = SYSTEM_CORE_CLOCK;                     /* System Clock Frequency (Core Clock) */
 
-static void SetSysClockTo96_HSE(void) {
+static void SetSysClock_HSE(void) {
   __IO uint32_t StartUpCounter = 0, HSEStatus = 0;
 
   RCC.CTLR.B.HSEON = SET;
@@ -45,7 +44,7 @@ static void SetSysClockTo96_HSE(void) {
       */
       r.B.PLLSRC   = SET;
       r.B.PLLXTPRE = RESET;
-      r.B.PLLMUL   = 10u;
+      r.B.PLLMUL   = 15u;     // or 10u for 96 MHz
       return r.R;
     });
     /* Enable PLL */
@@ -71,7 +70,7 @@ void SystemInit(void) {
   RCC.CTLR.R  &= 0xFFFBFFFFu;
   RCC.CFGR0.R &= 0xFF00FFFFu;
   RCC.INTR.R   = 0x009F0000u;    
-  SetSysClockTo96_HSE();
+  SetSysClock_HSE();
 }
 /*********************************************************************
  * @fn      SystemCoreClockUpdate
@@ -81,7 +80,7 @@ void SystemInit(void) {
  * @return  none
  */
 void SystemCoreClockUpdate (void) {
-  uint32_t tmp = 0, pllmull = 0, pllsource = 0, Pll_6_5 = 0;
+  uint32_t tmp = 0, pllmull = 0, pllsource = 0;
 
   tmp = RCC.CFGR0.B.SWS;
 
@@ -112,9 +111,6 @@ void SystemCoreClockUpdate (void) {
           SystemCoreClock = HSE_VALUE * pllmull;
         }
       }
-
-      if(Pll_6_5 == 1) SystemCoreClock = (SystemCoreClock / 2);
-
       break;
     default:
       SystemCoreClock = HSI_VALUE;
@@ -128,6 +124,7 @@ void SystemCoreClockUpdate (void) {
 static uint32_t p_us = 0u;
 static bool     timeout;
 void delay_init () {
+    // default clock is HCLK / 8
     p_us = SystemCoreClock / 8000000;
 }
 void delay_us (const unsigned dly) {
diff --git a/V203/usb/ch32v203/system.h b/V203/usb/ch32v203/system.h
index 9a57c76..b44ccf1 100644
--- a/V203/usb/ch32v203/system.h
+++ b/V203/usb/ch32v203/system.h
@@ -79,7 +79,7 @@ struct SysTick_Type {
     }
 };
 static SysTick_Type & SysTick = * reinterpret_cast<SysTick_Type * const> (0xE000F000);
-static constexpr unsigned SYSTEM_CORE_CLOCK = 96'000'000u;
+static constexpr unsigned SYSTEM_CORE_CLOCK = 144'000'000u; // or 96'000'000u
 extern "C" {
   extern uint32_t SystemCoreClock;
   extern void SystemCoreClockUpdate (void);