diff options
Diffstat (limited to 'src/c/hardware/avr/uart/u8AVRUARTSetups.c')
| -rw-r--r-- | src/c/hardware/avr/uart/u8AVRUARTSetups.c | 215 |
1 files changed, 137 insertions, 78 deletions
diff --git a/src/c/hardware/avr/uart/u8AVRUARTSetups.c b/src/c/hardware/avr/uart/u8AVRUARTSetups.c index f311500a..085ac6e3 100644 --- a/src/c/hardware/avr/uart/u8AVRUARTSetups.c +++ b/src/c/hardware/avr/uart/u8AVRUARTSetups.c @@ -1,84 +1,143 @@ -// Function to initialise uart interface of AVR -// -// Calling Sequence -// u8AVRUARTSetups(uint8 mode, uint8 baudrate, uint8 stopbits, uint8 parity) -// -// Parameters -// mode : Mode of usart interface (0-Normal mode, 1-Double speed mode, -// 2-Synchronous master mode) -// baudrate : Baudrate for communication. Refer AVRPeripheralUART.h -// for available options) -// stopbits : No. of stopbits (0-1) for stopbits 1 and 2 resp. -// parity: set parity bit. (0-disabled, 1-Even parity, 2-Odd parity) -// -// -// Description -// This function initialises uart interface for AVR. Available modes are -// Normal mode (0), Double speed mode (1), Synchronous master mode(2). 'baudrate' -// decides baudrate for communication. For baudrate settings, variable -// 'XTAL_FREQUENCY' is required. 'stopbits' sets no of stopbits for data -// packet. 0 for 1 stopbit and 1 for 2 stopbits. 'parity' decides parity bit -// for communication. 0 for disabling parity bit, 1 for even parity and 2 -// for odd parity. -// -// Authors -// Siddhesh Wani -// +/* Copyright (C) 2016 - IIT Bombay - FOSSEE + + This file must be used under the terms of the CeCILL. + This source file is licensed as described in the file COPYING, which + you should have received as part of this distribution. The terms + are also available at + http://www.cecill.info/licences/Licence_CeCILL_V2-en.txt + Author: Ashish Kamble + Organization: FOSSEE, IIT Bombay + Email: toolbox@scilab.in +*/ +//Function to Setup Serial communication for ATmega16. + #include "AVRPeripheralUART.h" -uint8 u8AVRUARTSetups(uint8 mode, uint8 baudrate, uint8 stopbits, uint8 parity) +uint8 u8AVRUARTSetups(uint8 mode, uint32 baudrate, uint8 stopbits, uint8 parity) +{ +//Enable UART and USART + UCSRC |= (1<<URSEL); + UCSRB |= (1<<TXEN)|(1<<RXEN); + + switch (mode) //According to mode set bits UMSEL and U2X +{ + case 0: //Normal mode + UCSRC &= ~(1<<UMSEL); //Clear bit 6 UMSEL and U2X=0 + UCSRA &= ~(1<<U2X); + UCSRC &= ~(1<<UCPOL); // Clock polarity bit + break; + + case 1: //Double speed mode + UCSRC &= ~(1<<UMSEL); //Clear bit 6 UMSEL and U2X=1 + UCSRA |= (1<<U2X); + UCSRC &= ~(1<<UCPOL); //Clock polarity bit + break; + + case 2: //Synchronous mode + UCSRC |= (1<<UMSEL); //Set bit 6 UMSEL and set clock polarity + UCSRC |= (1<<UCPOL); + break; +} + +//Set stop bits +if(stopbits == 0) +{ + UCSRC &= ~(1<<USBS); // 1 stopbit +} +else UCSRC |= (1<<USBS); //2 stopbits + +//Set parity bit settings +switch(parity) +{ + case 0: // Parity disabled + UCSRC &= ~(1<<UPM1); //UPM1:0=0 + UCSRC &= ~(1<<UPM0); + break; + + case 1: // Even parity + UCSRC |= (1<<UPM1); //UPM1:0 = 2 + UCSRC &= ~(1<<UPM0); + break; + + case 2: // Odd parity + UCSRC |= (1<<UPM1); //UPM1:1 = 3 + UCSRC |= (1<<UPM0); + break; +} + +//Set baudrate +UCSRC &= ~(1<<URSEL); +switch(baudrate) { - switch (mode) //According to mode set bits UMSEL and U2X - { - case 0: //Normal mode - UCSRC &= ~(1<<6); //Clear bit 6 UMSEL - break; - - case 1: //Double speed mode - UCSRC &= ~(1<<6); //Clear bit 6 UMSEL - break; - - case 2: //Synchronous master mode - UCSRC |= (1<<6); //Set bit 6 UMSEL - break; - } - - if(stopbits == 0) - { // 1 stopbit - UCSRC &= ~(1<<3); - } - else - { // 2 stopbits - UCSRC |= (1<<3); - } - - //Set parity bit settings - switch(parity) - { - case 0: // Parity disabled - UCSRC &= ~(3<<4); //UPM1:0=0 - break; - case 1:// Even parity - UCSRC |= (1<<5); //UPM1:0 = 2 - UCSRC &= ~(1<<4); - break; - case 2:// Odd parity - UCSRC |= (1<<5); //UPM1:1 = 3 - UCSRC |= (1<<4); - break; - } - - //Set baud rate - # define BAUD baudrate - #include "util/setbaud.h" - UBRRH = UBRRH_VALUE; - UBRRL = UBRRL_VALUE; - #if USE_2X - UCSRA |= (1 << U2X); - #else - UCSRA &= ~(1 << U2X); - #endif - return 0; + case 2400: + UBRRL = 0xA0; + UBRRH = 0x01; + break; + + case 4800: + UBRRL = 0xCF; + UBRRH = 0x00; + break; + + case 9600: + UBRRL = 0x67; + UBRRH = 0x00; + break; + + case 14400: + UBRRL = 0x44; + UBRRH = 0x00; + break; + + case 19200: + UBRRL = 0x33; + UBRRH = 0x00; + break; + + case 28800: + UBRRL = 0x22; + UBRRH = 0x00; + break; + + case 38400: + UBRRL = 0x19; + UBRRH = 0x00; + break; + + case 57600: + UBRRL = 0x10; + UBRRH = 0x00; + break; + + case 768000: + UBRRL = 0x0C; + UBRRH = 0x00; + break; + + case 115200: + UBRRL = 0x08; + UBRRH = 0x00; + break; + + case 230400: + UBRRL = 0x03; + UBRRH = 0x00; + break; + + case 250000: + UBRRL = 0x03; + UBRRH = 0x00; + break; + + case 1000000: + UBRRL = 0x00; + UBRRH = 0x00; + break; } +//Set data format +UCSRC|= (1<<URSEL)|(1<<UCSZ0)|(1<<UCSZ1); + + return 0; +} |