| 0,0 → 1,105 |
|---|
| #include "defines.h" |
| #include "UART1.h" |
| |
| static UART1_DATA *uart_data_ptr; |
| |
| /* Note: BRGH values are different from PIC18! |
| * |
| * Baud Rate Calculation (BRGH = 0): |
| * Baud Rate = PerfBusFreq / (16 * (BRG + 1)) |
| * BRG = PerfBusFreq / (16 * Baud Rate) - 1 |
| * |
| * Baud Rate Calculation (BRGH = 1): |
| * Baud Rate = PerfBusFreq / (4 * (BRG + 1)) |
| * BRG = PerfBusFreq / (4 * Baud Rate) - 1 |
| */ |
| |
| void UART1_Init(UART1_DATA *data, void (*rx_callback)(uint8_t)) { |
| uart_data_ptr = data; |
| uart_data_ptr->rx_callback = rx_callback; |
| uart_data_ptr->buffer_out_len = 0; |
| uart_data_ptr->buffer_out_ind = 0; |
| |
| INTDisableInterrupts(); |
| |
| IEC0CLR = 0x1C000000; // Disable all UART1 interrupts |
| IFS0CLR = 0x1C000000; // Clear any existing events |
| IPC6SET = 0x00000009; // Set Priority = 2, Subpriority = 1 |
| |
| U1MODE = 0x00008008; // UART enabled, BRGH = 1 |
| U1STA = 0x00009400; // TX interrupt on buffer empty, RX interrupt on buffer not empty |
| |
| // U1BRG = 173; // Set baud rate to 115200 @ 80MHz (0.22% error) |
| U1BRG = 86; // Set baud rate to 230400 @ 80MHz (0.22% error) |
| // U1BRG = 77; // Set baud rate to 256000 @ 80MHz (0.12% error) |
| // U1BRG = 42; // Set baud rate to 460800 @ 80MHz (0.94% error) |
| // U1BRG = 21; // Set baud rate to 921600 @ 80MHz (1.36% error) |
| |
| IEC0SET = 0x0C000000; // Enable the RX and Error interrupts |
| |
| INTEnableInterrupts(); |
| } |
| |
| uint8_t UART1_Write(uint8_t *string, uint32_t length) { |
| if (length > UART1_BUFFER_SIZE) |
| return 0; |
| if (uart_data_ptr->buffer_out_len != 0) |
| return 0; |
| |
| // Put the data to send into the outbound buffer |
| uart_data_ptr->buffer_out_len = length; |
| uart_data_ptr->buffer_out_ind = 0; |
| uint8_t i; |
| for (i = 0; i < length; i++) { |
| uart_data_ptr->buffer_out[i] = string[i]; |
| } |
| IEC0SET = 0x10000000; // Enable TX interrupt |
| return 1; |
| } |
| |
| void __ISR(_UART_1_VECTOR, ipl2) __UART_1_Interrupt_Handler(void) { |
| // Process UART1 error flag |
| if (IFS0bits.U1EIF) { |
| if (U1STAbits.PERR) { // Process parity error |
| |
| } |
| if (U1STAbits.FERR) { // Process frame error |
| |
| } |
| if (U1STAbits.OERR) { // Process receive buffer overrun error |
| U1STAbits.OERR = 0; // Clear the overrun error if set |
| } |
| IFS0CLR = 0x04000000; // Clear the error flag |
| } |
| |
| // Process UART1 recieve flag |
| if (IFS0bits.U1RXIF) { |
| // Read the data received from the last transfer |
| while (U1STAbits.URXDA) { |
| uint8_t c = U1RXREG; |
| // Call the RX callback function on each received data |
| if (uart_data_ptr->rx_callback != NULL) { |
| (*uart_data_ptr->rx_callback)(c); |
| } |
| } |
| IFS0CLR = 0x08000000; // Clear the recieve flag |
| } |
| |
| // Process UART1 transmit flag |
| if (IFS0bits.U1TXIF && IEC0bits.U1TXIE) { |
| // Disable the transmit interrupt if all data has been sent |
| if (uart_data_ptr->buffer_out_ind == uart_data_ptr->buffer_out_len) { |
| IEC0CLR = 0x10000000; |
| uart_data_ptr->buffer_out_len = 0; |
| } else { |
| // Start filling the transmit buffer |
| while (!U1STAbits.UTXBF) { |
| U1TXREG = uart_data_ptr->buffer_out[uart_data_ptr->buffer_out_ind]; |
| uart_data_ptr->buffer_out_ind++; |
| if (uart_data_ptr->buffer_out_ind == uart_data_ptr->buffer_out_len) |
| break; |
| } |
| } |
| IFS0CLR = 0x10000000; // Clear the transmit flag |
| } |
| } |