From 5db0144d4caec634af535d09831a2e8d22e31786 Mon Sep 17 00:00:00 2001
From: Ajit Ananthadevan <ntn.ajit@gmail.com>
Date: Thu, 21 Aug 2025 04:04:37 +1000
Subject: [PATCH] pcf8574-blinky v2

---
 myapps/misc/pcf8574-blinky-refac/Makefile     | 167 ++++++++++++++++++
 .../pcf8574-blinky-refac/src/inc/pcf8574.h    |  17 ++
 myapps/misc/pcf8574-blinky-refac/src/main.c   |  24 +++
 .../misc/pcf8574-blinky-refac/src/pcf8574.c   |  62 +++++++
 4 files changed, 270 insertions(+)
 create mode 100644 myapps/misc/pcf8574-blinky-refac/Makefile
 create mode 100644 myapps/misc/pcf8574-blinky-refac/src/inc/pcf8574.h
 create mode 100644 myapps/misc/pcf8574-blinky-refac/src/main.c
 create mode 100644 myapps/misc/pcf8574-blinky-refac/src/pcf8574.c

diff --git a/myapps/misc/pcf8574-blinky-refac/Makefile b/myapps/misc/pcf8574-blinky-refac/Makefile
new file mode 100644
index 0000000..b9bd730
--- /dev/null
+++ b/myapps/misc/pcf8574-blinky-refac/Makefile
@@ -0,0 +1,167 @@
+######################################
+# target
+######################################
+TARGET = ch592_blinky
+# ../../
+
+
+######################################
+# building variables
+######################################
+# debug build?
+DEBUG = 1
+# optimization for size
+OPT = -Os
+
+
+#######################################
+# paths
+#######################################
+# Build path
+BUILD_DIR = build
+
+######################################
+# source
+######################################
+# C sources
+C_SOURCES = \
+src/main.c \
+src/pcf8574.c \
+../../../vendor/StdPeriphDriver/CH59x_clk.c \
+../../../vendor/StdPeriphDriver/CH59x_gpio.c \
+../../../vendor/StdPeriphDriver/CH59x_pwr.c \
+../../../vendor/StdPeriphDriver/CH59x_sys.c \
+../../../vendor/StdPeriphDriver/CH59x_i2c.c \
+../../../vendor/RVMSIS/core_riscv.c \
+
+
+# ASM sources
+ASM_SOURCES =  \
+../../../vendor/Startup/startup_CH592.S
+
+#######################################
+# binaries
+#######################################
+#PREFIX = riscv-none-elf-
+#PREFIX = riscv64-elf-
+#debian
+#PREFIX = riscv64-unknown-elf-
+PREFIX = riscv-wch-elf-
+
+CC = $(PREFIX)gcc
+AS = $(PREFIX)gcc -x assembler-with-cpp
+CP = $(PREFIX)objcopy
+SZ = $(PREFIX)size
+
+HEX = $(CP) -O ihex
+BIN = $(CP) -O binary -S
+
+#######################################
+# CFLAGS
+#######################################
+# cpu
+CPU = -march=rv32imac_zicsr -mabi=ilp32 -msmall-data-limit=8 
+
+# For gcc version less than v12
+# CPU = -march=rv32imac -mabi=ilp32 -msmall-data-limit=8
+
+# fpu
+FPU = 
+
+# float-abi
+FLOAT-ABI =
+
+# mcu
+MCU = $(CPU) $(FPU) $(FLOAT-ABI)
+
+# AS includes
+AS_INCLUDES = 
+
+# C includes
+C_INCLUDES =  \
+-I../../../vendor/StdPeriphDriver/inc \
+-I../../../vendor/RVMSIS \
+-I../../../vendor/Core \
+-Isrc/inc
+
+# compile gcc flags
+ASFLAGS = $(MCU) $(AS_INCLUDES) $(OPT) -Wall -fdata-sections -ffunction-sections
+
+CFLAGS = $(MCU) $(C_INCLUDES) $(OPT) -Wall -fdata-sections -ffunction-sections
+
+ifeq ($(DEBUG), 1)
+CFLAGS += -g -gdwarf-2
+endif
+
+
+# Generate dependency information
+CFLAGS += -MMD -MP -MF"$(@:%.o=%.d)"
+
+
+#######################################
+# LDFLAGS
+#######################################
+# link script
+LDSCRIPT = ../../../vendor/Ld/Link.ld 
+
+# libraries
+LIBS = -lc -lm -lnosys ../../../vendor/StdPeriphDriver/libISP592.a
+LIBDIR = 
+LDFLAGS = $(MCU) -mno-save-restore -fmessage-length=0 -fsigned-char -ffunction-sections -fdata-sections -Wunused -Wuninitialized -T $(LDSCRIPT) -nostartfiles -Xlinker --gc-sections -Wl,-Map=$(BUILD_DIR)/$(TARGET).map --specs=nano.specs $(LIBS)
+
+# default action: build all
+all: $(BUILD_DIR)/$(TARGET).elf $(BUILD_DIR)/$(TARGET).hex $(BUILD_DIR)/$(TARGET).bin
+
+
+#######################################
+# build the application
+#######################################
+# list of objects
+OBJECTS = $(addprefix $(BUILD_DIR)/,$(notdir $(C_SOURCES:.c=.o)))
+vpath %.c $(sort $(dir $(C_SOURCES)))
+
+# list of ASM program objects
+OBJECTS += $(addprefix $(BUILD_DIR)/,$(notdir $(ASM_SOURCES:.S=.o)))
+vpath %.S $(sort $(dir $(ASM_SOURCES)))
+
+$(BUILD_DIR)/%.o: %.c Makefile | $(BUILD_DIR)
+	$(CC) -c $(CFLAGS) -Wa,-a,-ad,-alms=$(BUILD_DIR)/$(notdir $(<:.c=.lst)) $< -o $@
+
+$(BUILD_DIR)/%.o: %.S Makefile | $(BUILD_DIR)
+	$(AS) -c $(CFLAGS) $< -o $@
+#$(LUAOBJECTS) $(OBJECTS)
+$(BUILD_DIR)/$(TARGET).elf: $(OBJECTS) Makefile
+	$(CC) $(OBJECTS) $(LDFLAGS) -o $@
+	$(SZ) $@
+
+$(BUILD_DIR)/%.hex: $(BUILD_DIR)/%.elf | $(BUILD_DIR)
+	$(HEX) $< $@
+	
+$(BUILD_DIR)/%.bin: $(BUILD_DIR)/%.elf | $(BUILD_DIR)
+	$(BIN) $< $@	
+	
+$(BUILD_DIR):
+	mkdir $@		
+
+#######################################
+# Program
+#######################################
+
+isp: $(BUILD_DIR)/$(TARGET).bin
+	wchisp flash $(BUILD_DIR)/$(TARGET).bin
+
+flash: $(BUILD_DIR)/$(TARGET).bin
+	wlink flash $(BUILD_DIR)/$(TARGET).bin
+
+#######################################
+# clean up
+#######################################
+clean:
+	-rm -fR $(BUILD_DIR)
+  
+#######################################
+# dependencies
+#######################################
+-include $(wildcard $(BUILD_DIR)/*.d)
+
+# *** EOF ***
diff --git a/myapps/misc/pcf8574-blinky-refac/src/inc/pcf8574.h b/myapps/misc/pcf8574-blinky-refac/src/inc/pcf8574.h
new file mode 100644
index 0000000..5299f00
--- /dev/null
+++ b/myapps/misc/pcf8574-blinky-refac/src/inc/pcf8574.h
@@ -0,0 +1,17 @@
+// PCF8574 driver header
+
+
+#define PCFP0 0x01
+#define PCFP1 0x02
+#define PCFP2 0x04
+#define PCFP3 0x08
+#define PCFP4 0x10
+#define PCFP5 0x20
+#define PCFP6 0x40
+#define PCFP7 0x80   //128
+
+void pcf_init();
+
+void pcf_setbits(uint8_t ports);
+void pcf_resetbits(uint8_t ports);
+
diff --git a/myapps/misc/pcf8574-blinky-refac/src/main.c b/myapps/misc/pcf8574-blinky-refac/src/main.c
new file mode 100644
index 0000000..0fee7cc
--- /dev/null
+++ b/myapps/misc/pcf8574-blinky-refac/src/main.c
@@ -0,0 +1,24 @@
+// LED on PORT0
+
+
+#include "CH59x_common.h"
+#include "pcf8574.h"
+
+
+int main()
+{
+  SetSysClock(CLK_SOURCE_PLL_60MHz);
+  
+  pcf_init();
+  
+  pcf_setbits(PCFP0);
+  
+  while (1) {
+    mDelaymS(400);
+    pcf_resetbits(PCFP0);
+    
+    mDelaymS(100);
+    pcf_setbits(PCFP0);    
+  }
+}
+
diff --git a/myapps/misc/pcf8574-blinky-refac/src/pcf8574.c b/myapps/misc/pcf8574-blinky-refac/src/pcf8574.c
new file mode 100644
index 0000000..ca6db2c
--- /dev/null
+++ b/myapps/misc/pcf8574-blinky-refac/src/pcf8574.c
@@ -0,0 +1,62 @@
+// PCF8574 driver
+
+#include "CH59x_common.h"
+#include "pcf8574.h"
+
+#define I2C_OWNADD  0x0001
+
+
+void pcf_init()
+{
+  I2C_Init(I2C_Mode_I2C, 100000, I2C_DutyCycle_16_9,
+              I2C_Ack_Enable, I2C_AckAddr_7bit, I2C_OWNADD);
+  I2C_GenerateSTART(ENABLE);
+  while (!I2C_CheckEvent(I2C_EVENT_MASTER_MODE_SELECT));
+  I2C_Send7bitAddress(0x40, I2C_Direction_Transmitter);
+  while (!I2C_CheckEvent(I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
+  I2C_SendData(0xFF);
+  while (!I2C_CheckEvent(I2C_EVENT_MASTER_BYTE_TRANSMITTED));
+  I2C_GenerateSTOP(ENABLE);
+}
+
+/*
+ * set the ports OR'd together like: PCFP0 | PCFP1
+ */
+void pcf_setbits(uint8_t ports)
+{
+  I2C_GenerateSTART(ENABLE);
+  while (!I2C_CheckEvent(I2C_EVENT_MASTER_MODE_SELECT));
+  I2C_Send7bitAddress(0x41, I2C_Direction_Receiver);
+  while (!I2C_CheckEvent(I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED));
+  uint8_t curr = I2C_ReceiveData();
+  while (!I2C_CheckEvent(I2C_EVENT_MASTER_BYTE_RECEIVED));
+  I2C_GenerateSTOP(ENABLE);
+  
+  I2C_GenerateSTART(ENABLE);
+  while (!I2C_CheckEvent(I2C_EVENT_MASTER_MODE_SELECT));
+  I2C_Send7bitAddress(0x40, I2C_Direction_Transmitter);
+  while (!I2C_CheckEvent(I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
+  I2C_SendData(curr | ports);
+  while (!I2C_CheckEvent(I2C_EVENT_MASTER_BYTE_TRANSMITTED));
+  I2C_GenerateSTOP(ENABLE);
+}
+
+void pcf_resetbits(uint8_t ports)
+{
+  I2C_GenerateSTART(ENABLE);
+  while (!I2C_CheckEvent(I2C_EVENT_MASTER_MODE_SELECT));
+  I2C_Send7bitAddress(0x41, I2C_Direction_Receiver);
+  while (!I2C_CheckEvent(I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED));
+  uint8_t curr = I2C_ReceiveData();
+  while (!I2C_CheckEvent(I2C_EVENT_MASTER_BYTE_RECEIVED));
+  I2C_GenerateSTOP(ENABLE);
+  
+  I2C_GenerateSTART(ENABLE);
+  while (!I2C_CheckEvent(I2C_EVENT_MASTER_MODE_SELECT));
+  I2C_Send7bitAddress(0x40, I2C_Direction_Transmitter);
+  while (!I2C_CheckEvent(I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
+  I2C_SendData(curr & ~(ports));
+  while (!I2C_CheckEvent(I2C_EVENT_MASTER_BYTE_TRANSMITTED));
+  I2C_GenerateSTOP(ENABLE);
+}
+