add sinus generator

pwm/Makefile

@@ -0,0 +1,55 @@
+# ch32v003
+TARGET?= ch32v003
+TOOL  ?= gcc
+#TOOL  ?= clang
+
+
+PRJ    = example
+
+VPATH  = . ./$(TARGET)
+BLD    = ./build/
+DFLAGS = -d
+LFLAGS = -g
+LDLIBS =
+BFLAGS = --strip-unneeded
+
+CFLAGS = -MMD -Wall -ggdb -fno-exceptions -ffunction-sections -fdata-sections
+CFLAGS+= -I. -I./$(TARGET) -I/usr/include/newlib
+DEL    = rm -f
+
+# zdrojaky
+OBJS   = main.o pwmclass.o generator.o sin.o
+
+include $(TARGET)/$(TOOL).mk
+BOBJS = $(addprefix $(BLD),$(OBJS))
+
+all: $(BLD) $(PRJ).elf
+# ... atd.
+-include $(BLD)*.d
+# linker
+$(PRJ).elf: $(BOBJS)
+	-@echo [LD $(TOOL),$(TARGET)] $@
+	@$(LD) $(LFLAGS) -o $(PRJ).elf $(BOBJS) $(LDLIBS)
+	-@echo "size:"
+	@$(SIZE) $(PRJ).elf
+	-@echo "listing:"
+	$(DUMP) $(DFLAGS) $(PRJ).elf > $(PRJ).lst
+	-@echo "OK."
+	$(COPY) $(BFLAGS) -O binary $(PRJ).elf $(PRJ).bin
+# preloz co je potreba
+$(BLD)%.o: %.c
+	-@echo [CC $(TOOL),$(TARGET)] $@
+	@$(CC) -c $(CFLAGS) $< -o $@
+$(BLD)%.o: %.cpp
+	-@echo [CX $(TOOL),$(TARGET)] $@
+	@$(CXX) -std=c++17 -fno-rtti -c $(CFLAGS) $< -o $@
+$(BLD):
+	mkdir $(BLD)
+sin.c: sin.py
+	./sin.py
+flash: $(PRJ).elf
+	minichlink -w $(PRJ).bin flash -b
+# vycisti
+clean:
+	$(DEL) $(BLD)* *.lst *.bin *.elf *.map sin.c *~
+.PHONY: all clean

pwm/ch32v003

@@ -0,0 +1 @@
+../ch32v003/

pwm/generator.cpp

@@ -0,0 +1,13 @@
+#include "generator.h"
+
+extern "C" const uint16_t sin_tab[0x100];
+
+uint16_t Generator::step() {
+  const uint16_t v = sin_tab [base >> 24];
+  base += freq;
+  return v;
+}
+unsigned int Generator::Send(uint16_t * const ptr, const unsigned int len) {
+  for (unsigned n=0u; n<len; n++) ptr [n] = step();
+  return len;
+}

pwm/generator.h

@@ -0,0 +1,14 @@
+#ifndef GENERATOR_H
+#define GENERATOR_H
+#include "oneway.h"
+/* Něco jako DDS, přesná frekvence není řešena (závisí na TIM1). */
+class Generator : public OneWay {
+  unsigned base, freq;
+  public:
+    explicit Generator (const unsigned f) noexcept : OneWay(), base(0u), freq (f) {};
+    unsigned Send (uint16_t * const ptr, const unsigned len) override;
+  protected:
+    uint16_t step ();
+};
+
+#endif // GENERATOR_H

pwm/main.cpp

@@ -0,0 +1,16 @@
+#include "pwmclass.h"
+#include "generator.h"
+//////////////////////////////////////
+/* Demonstrace PWM s použitím DMA
+ * Generátor je sinus, data se tvoří
+ * v přerušení. Parametry se musí nastavit
+ * ve zdrojácích, je to jen DEMO.
+ * */
+//////////////////////////////////////
+static  PwmClass  pwm;
+static  Generator gen (1u << 16);
+int main () {
+  pwm.attach(gen);
+  for (;;);
+  return 0;
+}

pwm/oneway.h

@@ -0,0 +1,10 @@
+#ifndef ONEWAY_H
+#define ONEWAY_H
+#include <stdint.h>
+/* C++ interface (jako callback v C) */
+class OneWay {
+  public:
+    virtual unsigned Send (uint16_t * const ptr, const unsigned len) = 0;
+};
+
+#endif // ONEWAY_H

pwm/pwmclass.cpp

@@ -0,0 +1,103 @@
+#include "system.h"
+#include "pwmclass.h"
+#include "gpio.h"
+
+static PwmClass * pInstance = nullptr;
+extern "C" void DMA1_Channel5_IRQHandler( void ) __attribute__((interrupt));
+void DMA1_Channel5_IRQHandler( void ) {
+  DMA1_Type::INTFR_DEF state (DMA1.INTFR);
+  DMA1.INTFCR.R = state.R;  // clear all
+  if (!pInstance) return;
+  if      (state.B.HTIF5 != RESET) pInstance->send(false);
+  else if (state.B.TCIF5 != RESET) pInstance->send(true);
+}
+
+/*
+ * initialize TIM1 for PWM
+ */
+static inline void tim1pwm_init () noexcept {
+	// Enable GPIOD and TIM1
+  RCC.APB2PCENR.modify([] (RCC_Type::APB2PCENR_DEF & r) -> auto {
+    r.B.IOPDEN = SET;
+    r.B.TIM1EN = SET;
+    return r.R;
+  });
+    // PD0 is T1CH1N, PD2 is T1CH1, 10MHz Output alt func, push-pull
+  GPIOD.CFGLR.modify([](GPIOA_Type::CFGLR_DEF & r) -> auto {
+    r.B.CNF0  = 2u;
+    r.B.MODE0 = 1u;
+    r.B.CNF2  = 2u;
+    r.B.MODE2 = 1u;
+    return r.R;
+  });
+	// Reset TIM1 to init all regs
+  RCC.APB2PRSTR.B.TIM1RST = SET;
+  RCC.APB2PRSTR.B.TIM1RST = RESET;
+	// CTLR1: default is up, events generated, edge align
+	// SMCFGR: default clk input is CK_INT
+	// Prescaler 
+  TIM1.PSC.R = 0u;
+	// Auto Reload - sets period
+  TIM1.ATRLR.R = MAXPWM - 1;
+  
+  TIM1.CCER.modify([](TIM1_Type::CCER_DEF & r) -> auto {
+	// Enable CH1N, CH1 output, positive pol
+    r.B.CC1NE = SET;
+    r.B.CC1E  = SET;
+    /*
+    r.B.CC1NP = SET; // active Low
+    r.B.CC1P  = SET;
+    */
+    return r.R;
+  });
+	// CH1 Mode is output, PWM1 (CC1S = 00, OC1M = 110)
+  TIM1.CHCTLR1_Output.modify([](TIM1_Type::CHCTLR1_Output_DEF & r) -> auto {
+    r.B.OC1M = 0x6u;
+    return r.R;
+  });
+	// Enable TIM1 outputs
+  TIM1.BDTR.modify([](TIM1_Type::BDTR_DEF & r) -> auto {
+    r.B.MOE = SET;
+    r.B.DTG = 48u;  // Dead time 1us
+    return r.R;
+  });
+  
+	// Reload immediately + Trigger DMA
+  TIM1.SWEVGR.B.UG     = SET;
+  TIM1.DMAINTENR.B.UDE = SET;
+	// Enable TIM1
+  TIM1.CTLR1.B.CEN     = SET;
+}
+typedef __SIZE_TYPE__ size_t;
+static void dma1ch5_init (void * ptr) {
+	// Enable DMA
+  RCC.AHBPCENR.modify([](RCC_Type::AHBPCENR_DEF & r) -> auto {
+    r.B.SRAMEN = SET;
+    r.B.DMA1EN = SET;
+    return r.R;
+  });
+	// DMA5 can be configured to attach to T1UP
+	// The system can only DMA out at ~2.2MSPS.  2MHz is stable.
+  DMA1.CNTR5.R  = FULL_LEN;
+  DMA1.MADDR5.R = reinterpret_cast<size_t>(ptr);
+  DMA1.PADDR5.R = reinterpret_cast<size_t>(& TIM1.CH1CVR);
+  DMA1.CFGR5.modify([](DMA1_Type::CFGR5_DEF & r) -> auto {
+    r.B.DIR   = SET;                    // MEM2PERIPHERAL
+    r.B.PL    = 2u;                     // High priority.
+    r.B.PSIZE = 1u;                     // 16-bit peripheral
+    r.B.MSIZE = 1u;                     // 16-bit memory
+    r.B.MINC  = SET;                    // Increase memory.
+    r.B.CIRC  = SET;                    // Circular mode.
+    r.B.HTIE  = SET;                    // Half-trigger
+    r.B.TCIE  = SET;                    // Whole-trigger
+    return r.R;
+  });
+  NVIC.EnableIRQ (DMA1_Channel5_IRQn);
+  DMA1.CFGR5.B.EN = SET;
+}
+
+PwmClass::PwmClass() noexcept : pL(buffer), pH(buffer + HALF_LEN), src(nullptr) {
+  pInstance = this;
+  tim1pwm_init ();
+  dma1ch5_init (buffer);
+}

pwm/pwmclass.h

@@ -0,0 +1,23 @@
+#ifndef PWMCLASS_H
+#define PWMCLASS_H
+#include "oneway.h"
+static constexpr unsigned HALF_LEN = 64u;
+static constexpr unsigned FULL_LEN = 2u * HALF_LEN;
+static constexpr unsigned MAXPWM   = 2048u;
+/* Používá TIM1, PWM kanál 1, DMA1 kanál 5, přerušení DMA1_Channel5_IRQHandler */
+class PwmClass {
+  uint16_t * const pL;
+  uint16_t * const pH;
+  uint16_t buffer [FULL_LEN];
+  OneWay * src;
+  public:
+    explicit PwmClass () noexcept;
+    void attach (OneWay & s) { src = & s; }
+    void send (const bool b) {
+      if (!src) return;
+      if (b) src->Send (pH, HALF_LEN);
+      else   src->Send (pL, HALF_LEN);
+    }
+};
+
+#endif // PWMCLASS_H

pwm/sin.py

@@ -0,0 +1,27 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+
+import math
+
+header = '''/* Generated file */
+#include <stdint.h>
+const uint16_t sin_tab[] = {{{0:s}
+}};
+'''
+
+def generate():
+  s = ''
+  for n in range(0,256):
+    if (n % 16) == 0:
+      s += '\n  '
+    a  = float(n) * math.pi / 128.0
+    v  = int (round (1024.0 * (1.0 + math.sin (a))));
+    s += '{0:+6d},'.format(v)
+  return s
+
+if __name__ == '__main__':
+  s = generate()
+  f = open ('sin.c','w')
+  f.write(header.format(s))
+  f.close()
+