copied and adapted example from mdk, added init and config uart

having a program that runs on esp32-c3

Should initilize and config uart according to technical reference

Transmitting a simple message to test our if we get it

src/uart-transmit/esp32-c3-uart-interface.h

 #ifndef ESP32_C3_UART_INTERFACE_H
 #define ESP32_C3_UART_INTERFACE_H
 
-#define C3_SYSTEM_PERIP_CLK_EN0_REG ((volatile uint32_t *)0x0010)
+// all addresses are relative to some other register....
+
+#define C3_BASE_OFFSET_UART_CONTROLLER_0 ((uint32_t)0x60000000)
+#define C3_BASE_OFFSET_UART_CONTROLLER_1 ((uint32_t)0x60010000)
+#define C3_BASE_OFFSET_SYSTEM_REGISTERS ((uint32_t)0x600C0000)
+#define C3_BASE_OFFSET_SYSTEM_REGISTERS ((uint32_t)0x600C0000)
+#define C3_BASE_OFFSET_SYSTEM_REGISTERS ((uint32_t)0x600C0000)
+
+#define C3_UART_FIFO_REG_UART0 ((volatile uint32_t *)C3_BASE_OFFSET_UART_CONTROLLER_0+0x0000)
+#define C3_UART_FIFO_REG_UART1 ((volatile uint32_t *)C3_BASE_OFFSET_UART_CONTROLLER_1+0x0000)
+// UART_RXFIFO_RD_BYTE is from 0 to 7
+
+#define C3_UART_INT_ENA_REG_UART0 ((volatile uint32_t *)C3_BASE_OFFSET_UART_CONTROLLER_0+0x000C)
+#define C3_UART_INT_ENA_REG_UART1 ((volatile uint32_t *)C3_BASE_OFFSET_UART_CONTROLLER_1+0x000C)
+// UART_TXFIFO_EMPTY_INT_ENA is on 1
+
+#define C3_UART_INT_CLR_REG_UART0 ((volatile uint32_t *)C3_BASE_OFFSET_UART_CONTROLLER_0+0x0010)
+#define C3_UART_INT_CLR_REG_UART1 ((volatile uint32_t *)C3_BASE_OFFSET_UART_CONTROLLER_1+0x0010)
+// UART_TXFIFO_EMPTY_INT_CLR
+
+#define C3_SYSTEM_PERIP_CLK_EN0_REG ((volatile uint32_t *)C3_BASE_OFFSET_SYSTEM_REGISTERS+0x0010)
 // SYSTEM_UART_MEM_CLK_EN is on 24
 // SYSTEM_UARTn_CLK_EN n=0 is on 2, n=1 is on 5
 
-#define C3_UART_CLKDIV_REG ((volatile uint32_t *)0x0014)
+#define C3_UART_CLKDIV_REG_UART0 ((volatile uint32_t *)C3_BASE_OFFSET_UART_CONTROLLER_0+0x0014)
+#define C3_UART_CLKDIV_REG_UART1 ((volatile uint32_t *)C3_BASE_OFFSET_UART_CONTROLLER_1+0x0014)
 // UART_CLKDIV - integer part of baud rate calculator devisor - 0 to 11
 // UART_CLKDIV_FRAG - numerator of devisor in baud rate calculator devisor
 
-#define C3_UART_RX_FILT_REG ((volatile uint32_t *)0x0018)
+#define C3_UART_RX_FILT_REG_UART0 ((volatile uint32_t *)C3_BASE_OFFSET_UART_CONTROLLER_0+0x0018)
+#define C3_UART_RX_FILT_REG_UART1 ((volatile uint32_t *)C3_BASE_OFFSET_UART_CONTROLLER_1+0x0018)
 // SYSTEM_UARTn_RST n=0 is on 2, n=1 is on 5
 
-#define C3_UART_CONF0_REG ((volatile uint32_t *)0x0020)
+#define C3_UART_CONF0_REG_UART0 ((volatile uint32_t *)C3_BASE_OFFSET_UART_CONTROLLER_0+0x0020)
+#define C3_UART_CONF0_REG_UART1 ((volatile uint32_t *)C3_BASE_OFFSET_UART_CONTROLLER_1+0x0020)
 // UART_PARITY is on 0
 // UART_PARITY_EN is on 1
 // UART_BIT_NUM is on 2 and 3
 
-#define C3_UART_CLK_CONF_REG ((volatile uint32_t *)0x0078)
+
+#define C3_UART_CONF1_REG_UART0 ((volatile uint32_t *)C3_BASE_OFFSET_UART_CONTROLLER_0+0x0024)
+#define C3_UART_CONF1_REG_UART1 ((volatile uint32_t *)C3_BASE_OFFSET_UART_CONTROLLER_1+0x0024)
+// UART_TXFIFO_EMPTY_THRHD is 9 to 17
+
+#define C3_UART_CLK_CONF_REG_UART0 ((volatile uint32_t *)C3_BASE_OFFSET_UART_CONTROLLER_0+0x0078)
+#define C3_UART_CLK_CONF_REG_UART1 ((volatile uint32_t *)C3_BASE_OFFSET_UART_CONTROLLER_1+0x0078)
 // UART_RST_CORE is on 23
 // UART_SCLK_SEL is on 20 and 21 (2 bits), selcetion is between 1 and 3
 // UART_SCLK_DIV_NUM - The integral part of the frequency divisor - 12 to 19
 // UART_SCLK_DIV_A - The numerator of the frequency divisor - 6 to 11
 // UART_SCLK_DIV_B - The denominator of the frequency divisor - 0 to 5
 
-#define C3_UART_ID_REG ((volatile uint32_t *)0x0080)
+#define C3_UART_ID_REG_UART0 ((volatile uint32_t *)C3_BASE_OFFSET_UART_CONTROLLER_0+0x0080)
+#define C3_UART_ID_REG_UART1 ((volatile uint32_t *)C3_BASE_OFFSET_UART_CONTROLLER_1+0x0080)
 // UART_UPDATE_CTRL is on 30
 // UART_REG_UPDATE is on 31