Hi Everybody,
I want to know what is wrong with the code below
I want to transmit Hello world to a lcd with i2c controller (ywrobot arduino lcm1602 iic v1)
The slave address for the i2c controller is 0x27
I don't know what is wrong, all i know that is stuck on: while ( TI_USCI_I2C_notready() ); when the following line exist: P1SEL2 |= SDA_PIN + SCL_PIN; // Assign I2C pins to USCI_B0 and when i remove it it pass the while condition but not display.
In P1.6 (SCL_PIN) AND P1.7(SDA_PIN ) i put 10k resistors.
I think the code i ok but still can't display.
what ways should i investigate? speed of lcd, maybe what i2c controller should get? any help/direction will be great.
Thank you all
-----------Code------- main.c-------
#include <inttypes.h>
#include "msp430.h"
#include "TI_USCI_I2C_master.h"
/*
* main.c
*/
void delay( unsigned int n ) {
volatile int i;
for( ; n; n-- ) {
for( i = 0; i < 50; i++ );
}
}
int main(void)
{
WDTCTL = WDTPW + WDTHOLD; // Stop WDT
BCSCTL1 = CALBC1_8MHZ;
DCOCTL = CALDCO_8MHZ;
TI_USCI_I2C_transmitinit(0x27, 12);
unsigned char transmit_string[40];
while ( TI_USCI_I2C_notready() );
TI_USCI_I2C_transmit(2, (unsigned char *) "\x00\x38");
while ( TI_USCI_I2C_notready() );
TI_USCI_I2C_transmit(1, (unsigned char *) "\x39"); // 8-bit bus, 2-line display, extension instruction mode.
while ( TI_USCI_I2C_notready() );
TI_USCI_I2C_transmit(7, (unsigned char *) "\x14\x78\x5e\x6d\x0c\x01\x06");
while ( TI_USCI_I2C_notready() );
TI_USCI_I2C_transmit(2, (unsigned char *) "\x00\x01");
while ( TI_USCI_I2C_notready() );
TI_USCI_I2C_transmit(21, (unsigned char *) "\x40Hello, world. ");
while(1) {
//Switch2Pressed = 0;
__bis_SR_register(LPM2_bits + GIE);
// __no_operation(); // For debugger
// while (i2c_avail()) {
// int c = i2c_getchar();
// i2c_putchar(c);
// }
}
return 0;
}
-----------Code------- TI_USCI_I2C_master.c-------
//******************************************************************************
// MSP430 USCI I2C Transmitter and Receiver
//
// Description: This code configures the MSP430's USCI module as
// I2C master capable of transmitting and receiving bytes.
//
// ***THIS IS THE MASTER CODE***
//
// Master
// MSP430F2619
// -----------------
// /|\| XIN|-
// | | |
// --|RST XOUT|-
// | |
// | |
// | |
// | SDA/P3.1|------->
// | SCL/P3.2|------->
//
// Note: External pull-ups are needed for SDA & SCL
//
// Uli Kretzschmar
// Texas Instruments Deutschland GmbH
// November 2007
// Built with IAR Embedded Workbench Version: 3.42A
//******************************************************************************
//#include "msp430x26x.h"
//#include "msp430x22x4.h"
//#include "msp430x23x0.h"
//#include "msp430xG46x.h"
// ... // more devices are possible
#include "msp430.h"
#include "TI_USCI_I2C_master.h"
signed char byteCtr;
unsigned char *TI_receive_field;
unsigned char *TI_transmit_field;
//------------------------------------------------------------------------------
// void TI_USCI_I2C_receiveinit(unsigned char slave_address,
// unsigned char prescale)
//
// This function initializes the USCI module for master-receive operation.
//
// IN: unsigned char slave_address => Slave Address
// unsigned char prescale => SCL clock adjustment
//-----------------------------------------------------------------------------
void TI_USCI_I2C_receiveinit(unsigned char slave_address,
unsigned char prescale){
P1SEL |= SDA_PIN + SCL_PIN; // Assign I2C pins to USCI_B0
P1SEL2 |= SDA_PIN + SCL_PIN; // Assign I2C pins to USCI_B0
UCB0CTL1 = UCSWRST; // Enable SW reset
UCB0CTL0 = UCMST + UCMODE_3 + UCSYNC; // I2C Master, synchronous mode
UCB0CTL1 = UCSSEL_2 + UCSWRST; // Use SMCLK, keep SW reset
UCB0BR0 = prescale; // set prescaler
UCB0BR1 = 0;
UCB0I2CSA = slave_address; // set slave address
UCB0CTL1 &= ~UCSWRST; // Clear SW reset, resume operation
UCB0I2CIE = UCNACKIE;
IE2 = UCB0RXIE; // Enable RX interrupt
}
//------------------------------------------------------------------------------
// void TI_USCI_I2C_transmitinit(unsigned char slave_address,
// unsigned char prescale)
//
// This function initializes the USCI module for master-transmit operation.
//
// IN: unsigned char slave_address => Slave Address
// unsigned char prescale => SCL clock adjustment
//------------------------------------------------------------------------------
void TI_USCI_I2C_transmitinit(unsigned char slave_address,
unsigned char prescale){
P1SEL |= SDA_PIN + SCL_PIN; // Assign I2C pins to USCI_B0
P1SEL2 |= SDA_PIN + SCL_PIN; // Assign I2C pins to USCI_B0
UCB0CTL1 = UCSWRST; // Enable SW reset
UCB0CTL0 = UCMST + UCMODE_3 + UCSYNC; // I2C Master, synchronous mode
UCB0CTL1 = UCSSEL_2 + UCSWRST; // Use SMCLK, keep SW reset
UCB0BR0 = prescale; // set prescaler
UCB0BR1 = 0;
UCB0I2CSA = slave_address; // Set slave address
UCB0CTL1 &= ~UCSWRST; // Clear SW reset, resume operation
UCB0I2CIE = UCNACKIE;
IE2 = UCB0TXIE; // Enable TX ready interrupt
}
//------------------------------------------------------------------------------
// void TI_USCI_I2C_receive(unsigned char byteCount, unsigned char *field)
//
// This function is used to start an I2C commuincation in master-receiver mode.
//
// IN: unsigned char byteCount => number of bytes that should be read
// unsigned char *field => array variable used to store received data
//------------------------------------------------------------------------------
void TI_USCI_I2C_receive(unsigned char byteCount, unsigned char *field){
TI_receive_field = field;
if ( byteCount == 1 ){
byteCtr = 0 ;
__disable_interrupt();
UCB0CTL1 |= UCTXSTT; // I2C start condition
while (UCB0CTL1 & UCTXSTT); // Start condition sent?
UCB0CTL1 |= UCTXSTP; // I2C stop condition
__enable_interrupt();
} else if ( byteCount > 1 ) {
byteCtr = byteCount - 2 ;
UCB0CTL1 |= UCTXSTT; // I2C start condition
} else
while (1); // illegal parameter
}
//------------------------------------------------------------------------------
// void TI_USCI_I2C_transmit(unsigned char byteCount, unsigned char *field)
//
// This function is used to start an I2C commuincation in master-transmit mode.
//
// IN: unsigned char byteCount => number of bytes that should be transmitted
// unsigned char *field => array variable. Its content will be sent.
//------------------------------------------------------------------------------
void TI_USCI_I2C_transmit(unsigned char byteCount, unsigned char *field){
TI_transmit_field = field;
byteCtr = byteCount;
UCB0CTL1 |= UCTR + UCTXSTT; // I2C TX, start condition
}
//------------------------------------------------------------------------------
// unsigned char TI_USCI_I2C_slave_present(unsigned char slave_address)
//
// This function is used to look for a slave address on the I2C bus.
//
// IN: unsigned char slave_address => Slave Address
// OUT: unsigned char => 0: address was not found,
// 1: address found
//------------------------------------------------------------------------------
unsigned char TI_USCI_I2C_slave_present(unsigned char slave_address){
unsigned char ie2_bak, slaveadr_bak, ucb0i2cie, returnValue;
ucb0i2cie = UCB0I2CIE; // restore old UCB0I2CIE
ie2_bak = IE2; // store IE2 register
slaveadr_bak = UCB0I2CSA; // store old slave address
UCB0I2CIE &= ~ UCNACKIE; // no NACK interrupt
UCB0I2CSA = slave_address; // set slave address
IE2 &= ~(UCB0TXIE + UCB0RXIE); // no RX or TX interrupts
__disable_interrupt();
UCB0CTL1 |= UCTR + UCTXSTT + UCTXSTP; // I2C TX, start condition
while (UCB0CTL1 & UCTXSTP); // wait for STOP condition
returnValue = !(UCB0STAT & UCNACKIFG);
__enable_interrupt();
IE2 = ie2_bak; // restore IE2
UCB0I2CSA = slaveadr_bak; // restore old slave address
UCB0I2CIE = ucb0i2cie; // restore old UCB0CTL1
return returnValue; // return whether or not
// a NACK occured
}
//------------------------------------------------------------------------------
// unsigned char TI_USCI_I2C_notready()
//
// This function is used to check if there is commuincation in progress.
//
// OUT: unsigned char => 0: I2C bus is idle,
// 1: communication is in progress
//------------------------------------------------------------------------------
unsigned char TI_USCI_I2C_notready(){
return (UCB0STAT & UCBBUSY);
}
#pragma vector = USCIAB0RX_VECTOR
__interrupt void USCIAB0RX_ISR(void)
{
if (UCB0STAT & UCNACKIFG){ // send STOP if slave sends NACK
UCB0CTL1 |= UCTXSTP;
UCB0STAT &= ~UCNACKIFG;
}
}
#pragma vector = USCIAB0TX_VECTOR
__interrupt void USCIAB0TX_ISR(void)
{
if (IFG2 & UCB0RXIFG){
if ( byteCtr == 0 ){
UCB0CTL1 |= UCTXSTP; // I2C stop condition
*TI_receive_field = UCB0RXBUF;
TI_receive_field++;
}
else {
*TI_receive_field = UCB0RXBUF;
TI_receive_field++;
byteCtr--;
}
}
else {
if (byteCtr == 0){
UCB0CTL1 |= UCTXSTP; // I2C stop condition
IFG2 &= ~UCB0TXIFG; // Clear USCI_B0 TX int flag
}
else {
UCB0TXBUF = *TI_transmit_field;
TI_transmit_field++;
byteCtr--;
}
}
}