diff --git a/examples/i2c_oled/Makefile b/examples/i2c_oled/Makefile
new file mode 100644
index 0000000000000000000000000000000000000000..a69a60cb705cb740c687912294bf8713b86298b0
--- /dev/null
+++ b/examples/i2c_oled/Makefile
@@ -0,0 +1,41 @@
+TARGET:=i2c_oled
+
+all : flash
+
+PREFIX:=riscv64-unknown-elf
+
+GPIO_Toggle:=EXAM/GPIO/GPIO_Toggle/User
+
+CH32V003FUN:=../../ch32v003fun
+MINICHLINK:=../../minichlink
+
+CFLAGS:= \
+ -g -Os -flto -ffunction-sections \
+ -static-libgcc -lgcc \
+ -march=rv32ec \
+ -mabi=ilp32e \
+ -I/usr/include/newlib \
+ -I$(CH32V003FUN) \
+ -nostdlib \
+ -I. -DSTDOUT_UART -Wall
+
+LDFLAGS:=-T $(CH32V003FUN)/ch32v003fun.ld -Wl,--gc-sections
+
+SYSTEM_C:=$(CH32V003FUN)/ch32v003fun.c
+
+$(TARGET).elf : $(SYSTEM_C) $(TARGET).c
+ $(PREFIX)-gcc -o $@ $^ $(CFLAGS) $(LDFLAGS)
+
+$(TARGET).bin : $(TARGET).elf
+ $(PREFIX)-size $^
+ $(PREFIX)-objdump -S $^ > $(TARGET).lst
+ $(PREFIX)-objdump -t $^ > $(TARGET).map
+ $(PREFIX)-objcopy -O binary $< $(TARGET).bin
+ $(PREFIX)-objcopy -O ihex $< $(TARGET).hex
+
+flash : $(TARGET).bin
+ $(MINICHLINK)/minichlink -w $< flash -b
+
+clean :
+ rm -rf $(TARGET).elf $(TARGET).bin $(TARGET).hex $(TARGET).lst $(TARGET).map $(TARGET).hex
+
diff --git a/examples/i2c_oled/i2c_oled.c b/examples/i2c_oled/i2c_oled.c
new file mode 100644
index 0000000000000000000000000000000000000000..f5d4286400de90430badc901e78469954214b746
--- /dev/null
+++ b/examples/i2c_oled/i2c_oled.c
@@ -0,0 +1,37 @@
+/*
+ * Example for using I2C with graphic OLED
+ * 03-29-2023 E. Brombaugh
+ */
+
+// Could be defined here, or in the processor defines.
+#define SYSTEM_CORE_CLOCK 48000000
+#define APB_CLOCK SYSTEM_CORE_CLOCK
+
+#include "ch32v003fun.h"
+#include <stdio.h>
+#include "oled.h"
+
+int main()
+{
+ uint32_t count = 0;
+
+ SystemInit48HSI();
+
+ // start serial @ default 115200bps
+ SetupUART( UART_BRR );
+ Delay_Ms( 100 );
+ printf("\r\r\n\ni2c_oled example\n\r");
+
+ // init i2c and oled
+ printf("initializing i2c oled...");
+ oled_init();
+ printf("done.\n\r");
+
+ printf("looping...\n\r");
+ while(1)
+ {
+ count++;
+ count &= 255;
+ Delay_Ms( 5 );
+ }
+}
diff --git a/examples/i2c_oled/oled.h b/examples/i2c_oled/oled.h
new file mode 100644
index 0000000000000000000000000000000000000000..693eac6454b63877d6d0c171931bc845fc73af5e
--- /dev/null
+++ b/examples/i2c_oled/oled.h
@@ -0,0 +1,387 @@
+/*
+ * Single-File-Header for using I2C OLED
+ * 03-29-2023 E. Brombaugh
+ */
+
+#ifndef _OLED_H
+#define _OLED_H
+
+#include <stdint.h>
+#include <string.h>
+
+// I2C clock rate
+#define I2C_CLKRATE 80000
+
+// OLED I2C address
+#define OLED_ADDR 0x3c
+
+// I2C Timeout count
+#define TIMEOUT_MAX 100000
+
+/*
+ * init I2C
+ */
+void i2c_init(void)
+{
+ uint16_t tempreg;
+
+ // Enable GPIOC and I2C
+ RCC->APB2PCENR |= RCC_APB2Periph_GPIOC;
+ RCC->APB1PCENR |= RCC_APB1Periph_I2C1;
+
+ // PC1/PC2 are SDA/SCL, 50MHz Output PP CNF = 11: Mux OD, MODE = 11: Out 50MHz
+ GPIOC->CFGLR &= ~(GPIO_CFGLR_MODE1 | GPIO_CFGLR_CNF1 |
+ GPIO_CFGLR_MODE1 | GPIO_CFGLR_CNF1);
+ GPIOC->CFGLR |= GPIO_CFGLR_CNF1_1 | GPIO_CFGLR_CNF1_0 |
+ GPIO_CFGLR_MODE1_1 | GPIO_CFGLR_MODE1_0 |
+ GPIO_CFGLR_CNF2_1 | GPIO_CFGLR_CNF2_0 |
+ GPIO_CFGLR_MODE2_1 | GPIO_CFGLR_MODE2_0;
+
+ // Reset I2C1 to init all regs
+ RCC->APB1PRSTR |= RCC_APB1Periph_I2C1;
+ RCC->APB1PRSTR &= ~RCC_APB1Periph_I2C1;
+
+ // set freq
+ tempreg = I2C1->CTLR2;
+ tempreg &= ~I2C_CTLR2_FREQ;
+ tempreg |= (APB_CLOCK/1000000)&I2C_CTLR2_FREQ;
+ I2C1->CTLR2 = tempreg;
+
+ // Set clock config
+ tempreg = 0;
+#if (I2C_CLKRATE <= 100000)
+ // standard mode good to 100kHz
+ tempreg = (APB_CLOCK/(2*I2C_CLKRATE))&I2C_CKCFGR_CCR;
+#else
+ // fast mode not yet handled here
+#endif
+ I2C1->CKCFGR = tempreg;
+
+ // Enable I2C
+ I2C1->CTLR1 |= I2C_CTLR1_PE;
+
+ // set ACK mode
+ I2C1->CTLR1 |= I2C_CTLR1_ACK;
+
+ // is this needed for a master?
+ I2C1->OADDR1 = 2;
+}
+
+/*
+ * error handler
+ */
+void i2c_error(void)
+{
+ // toggle SWRST bit
+ I2C1->CTLR1 |= I2C_CTLR1_SWRST;
+ I2C1->CTLR1 &= ~I2C_CTLR1_SWRST;
+}
+
+// event codes we use
+#define I2C_EVENT_MASTER_MODE_SELECT ((uint32_t)0x00030001) /* BUSY, MSL and SB flag */
+#define I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED ((uint32_t)0x00070082) /* BUSY, MSL, ADDR, TXE and TRA flags */
+#define I2C_EVENT_MASTER_BYTE_TRANSMITTED ((uint32_t)0x00070084) /* TRA, BUSY, MSL, TXE and BTF flags */
+
+/*
+ * check for 32-bit event codes
+ */
+uint8_t i2c_chk_evt(uint32_t event_mask)
+{
+ uint32_t status = (I2C1->STAR2<<16) | I2C1->STAR1;
+ return (status & event_mask) == event_mask;
+}
+
+/*
+ * send OLED command byte
+ */
+void oled_cmd(uint8_t cmd)
+{
+ int32_t timeout;
+
+ // wait for not busy
+ timeout = TIMEOUT_MAX;
+ while((I2C1->STAR2 & I2C_STAR2_BUSY) && (timeout--));
+ if(timeout==-1)
+ {
+ printf("oled_cmd - timeout waiting for not busy\n\r");
+ i2c_error();
+ return;
+ }
+
+ // Set START condition
+ I2C1->CTLR1 |= I2C_CTLR1_START;
+
+ // wait for master mode select
+ timeout = TIMEOUT_MAX;
+ while((!i2c_chk_evt(I2C_EVENT_MASTER_MODE_SELECT)) && (timeout--));
+ if(timeout==-1)
+ {
+ printf("oled_cmd - timeout waiting for master mode\n\r");
+ i2c_error();
+ return;
+ }
+
+ // send 7-bit address + write flag
+ I2C1->DATAR = OLED_ADDR<<1;
+
+ // wait for transmit condition
+ timeout = TIMEOUT_MAX;
+ while((!i2c_chk_evt(I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED)) && (timeout--));
+ if(timeout==-1)
+ {
+ printf("oled_cmd - timeout waiting for transmit mode\n\r");
+ i2c_error();
+ return;
+ }
+
+ // wait for TX Empty
+ timeout = TIMEOUT_MAX;
+ while(!(I2C1->STAR1 & I2C_STAR1_TXE) && (timeout--));
+ if(timeout==-1)
+ {
+ printf("oled_cmd - timeout waiting for tx empty\n\r");
+ i2c_error();
+ return;
+ }
+
+ // send command flag
+ I2C1->DATAR = 0;
+
+ // wait for TX Empty
+ timeout = TIMEOUT_MAX;
+ while(!(I2C1->STAR1 & I2C_STAR1_TXE) && (timeout--));
+ if(timeout==-1)
+ {
+ printf("oled_cmd - timeout waiting for tx empty\n\r");
+ i2c_error();
+ return;
+ }
+
+ // send command
+ I2C1->DATAR = cmd;
+
+ // wait for tx complete
+ timeout = TIMEOUT_MAX;
+ while((!i2c_chk_evt(I2C_EVENT_MASTER_BYTE_TRANSMITTED)) && (timeout--));
+ if(timeout==-1)
+ {
+ printf("oled_cmd - timeout waiting for byte transmitted\n\r");
+ i2c_error();
+ return;
+ }
+
+ // set STOP condition
+ I2C1->CTLR1 |= I2C_CTLR1_STOP;
+}
+
+/*
+ * send OLED data packet (up to 32 bytes)
+ */
+void oled_data(uint8_t *data, uint8_t sz)
+{
+ int32_t timeout;
+
+ // max 32 bytes
+ sz = sz > 32 ? 32 : sz;
+
+ // wait for not busy
+ timeout = TIMEOUT_MAX;
+ while((I2C1->STAR2 & I2C_STAR2_BUSY) && (timeout--));
+ if(timeout==-1)
+ {
+ printf("oled_data - timeout waiting for not busy\n\r");
+ i2c_error();
+ return;
+ }
+
+ // Set START condition
+ I2C1->CTLR1 |= I2C_CTLR1_START;
+
+ // wait for master mode select
+ timeout = TIMEOUT_MAX;
+ while((!i2c_chk_evt(I2C_EVENT_MASTER_MODE_SELECT)) && (timeout--));
+ if(timeout==-1)
+ {
+ printf("oled_data - timeout waiting for master mode\n\r");
+ i2c_error();
+ return;
+ }
+
+ // send 7-bit address + write flag
+ I2C1->DATAR = OLED_ADDR<<1;
+
+ // wait for transmit condition
+ timeout = TIMEOUT_MAX;
+ while((!i2c_chk_evt(I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED)) && (timeout--));
+ if(timeout==-1)
+ {
+ printf("oled_data - timeout waiting for transmit mode\n\r");
+ i2c_error();
+ return;
+ }
+
+ // wait for TX Empty
+ timeout = TIMEOUT_MAX;
+ while(!(I2C1->STAR1 & I2C_STAR1_TXE) && (timeout--));
+ if(timeout==-1)
+ {
+ printf("oled_data - timeout waiting for tx empty\n\r");
+ i2c_error();
+ return;
+ }
+
+ // send data flag
+ I2C1->DATAR = 0x40;
+
+ // send data one byte at a time
+ while(sz--)
+ {
+ // wait for TX Empty
+ timeout = TIMEOUT_MAX;
+ while(!(I2C1->STAR1 & I2C_STAR1_TXE) && (timeout--));
+ if(timeout==-1)
+ {
+ printf("oled_cmd - timeout waiting for tx empty\n\r");
+ i2c_error();
+ return;
+ }
+
+ // send command
+ I2C1->DATAR = *data++;
+ }
+
+ // wait for tx complete
+ timeout = TIMEOUT_MAX;
+ while((!i2c_chk_evt(I2C_EVENT_MASTER_BYTE_TRANSMITTED)) && (timeout--));
+ if(timeout==-1)
+ {
+ printf("oled_data - timeout waiting for byte transmitted\n\r");
+ i2c_error();
+ return;
+ }
+
+ // set STOP condition
+ I2C1->CTLR1 |= I2C_CTLR1_STOP;
+}
+
+#define SSD1306_SETCONTRAST 0x81
+#define SSD1306_SEGREMAP 0xA0
+#define SSD1306_DISPLAYALLON_RESUME 0xA4
+#define SSD1306_DISPLAYALLON 0xA5
+#define SSD1306_NORMALDISPLAY 0xA6
+#define SSD1306_INVERTDISPLAY 0xA7
+#define SSD1306_DISPLAYOFF 0xAE
+#define SSD1306_DISPLAYON 0xAF
+#define SSD1306_SETDISPLAYOFFSET 0xD3
+#define SSD1306_SETCOMPINS 0xDA
+#define SSD1306_SETVCOMDETECT 0xDB
+#define SSD1306_SETDISPLAYCLOCKDIV 0xD5
+#define SSD1306_SETPRECHARGE 0xD9
+#define SSD1306_SETMULTIPLEX 0xA8
+#define SSD1306_SETLOWCOLUMN 0x00
+#define SSD1306_SETHIGHCOLUMN 0x10
+#define SSD1306_SETSTARTLINE 0x40
+#define SSD1306_MEMORYMODE 0x20
+#define SSD1306_COLUMNADDR 0x21
+#define SSD1306_PAGEADDR 0x22
+#define SSD1306_COMSCANINC 0xC0
+#define SSD1306_COMSCANDEC 0xC8
+#define SSD1306_CHARGEPUMP 0x8D
+#define SSD1306_EXTERNALVCC 0x1
+#define SSD1306_SWITCHCAPVCC 0x2
+#define SSD1306_TERMINATE_CMDS 0xFF
+
+/* choose VCC mode */
+#define SSD1306_EXTERNALVCC 0x1
+#define SSD1306_SWITCHCAPVCC 0x2
+//#define vccstate SSD1306_EXTERNALVCC
+#define vccstate SSD1306_SWITCHCAPVCC
+
+// OLED initialization commands for 64x32
+uint8_t oled_init_array[] =
+{
+ SSD1306_DISPLAYOFF, // 0xAE
+ SSD1306_SETDISPLAYCLOCKDIV, // 0xD5
+ 0x80, // the suggested ratio 0x80
+ SSD1306_SETMULTIPLEX, // 0xA8
+ 0x1F, // different for tiny
+ SSD1306_SETDISPLAYOFFSET, // 0xD3
+ 0x00, // no offset
+ SSD1306_SETSTARTLINE | 0x0, // 0x40 | line
+ SSD1306_CHARGEPUMP, // 0x8D
+ 0x14, // enable?
+ SSD1306_MEMORYMODE, // 0x20
+ 0x00, // 0x0 act like ks0108
+ SSD1306_SEGREMAP | 0x1, // 0xA0 | bit
+ SSD1306_COMSCANDEC,
+ SSD1306_SETCOMPINS, // 0xDA
+ 0x12,
+ SSD1306_SETCONTRAST, // 0x81
+ 0x8F,
+ SSD1306_SETPRECHARGE, // 0xd9
+ 0xF1,
+ SSD1306_SETVCOMDETECT, // 0xDB
+ 0x40,
+ SSD1306_DISPLAYALLON_RESUME, // 0xA4
+ SSD1306_NORMALDISPLAY, // 0xA6
+ SSD1306_DISPLAYON, // 0xAF --turn on oled panel
+ SSD1306_TERMINATE_CMDS // 0xFF --fake command to mark end
+};
+#define OLED_W 64
+#define OLED_H 32
+
+// the display buffer
+uint8_t oled_buffer[128*32/8];
+
+/*
+ * set the buffer to a color
+ */
+void oled_setbuf(uint8_t color)
+{
+ memset(oled_buffer, color ? 0xFF : 0x00, sizeof(oled_buffer));
+}
+
+/*
+ * Send the frame buffer
+ */
+void oled_refresh(void)
+{
+ uint16_t i;
+
+ oled_cmd(SSD1306_COLUMNADDR);
+ oled_cmd(0); // Column start address (0 = reset)
+ oled_cmd(OLED_W-1); // Column end address (127 = reset)
+
+ oled_cmd(SSD1306_PAGEADDR);
+ oled_cmd(4); // Page start address (0 = reset)
+ oled_cmd(7); // Page end address
+
+ for (i=0;i<sizeof(oled_buffer);i+=16)
+ {
+ /* send a block of data */
+ oled_data(&oled_buffer[i], 16);
+ }
+}
+
+/*
+ * initialize act
+ */
+void oled_init( void )
+{
+ // initialize port
+ i2c_init();
+
+ // initialize OLED
+ uint8_t *cmd_list = oled_init_array;
+ while(*cmd_list != SSD1306_TERMINATE_CMDS)
+ {
+ oled_cmd(*cmd_list++);
+ }
+ printf("oled_init - list complete\n\r");
+
+ // clear display
+ oled_setbuf(0);
+ oled_refresh();
+}
+
+#endif