mam problem z przeniesieniem pewnego kodu napisanego pod atmegę328 na xmegę128A3. Chodzi tutaj o obsługę czujnika LSP25H, magistrala I2C.
Oto kod pod atmegę328:
[syntax=c]#define F_CPU 16000000UL
#include <util/delay.h>
#include <avr/io.h>
#include "uart.c"
//set up stdout and stdin
static FILE mystdout = FDEV_SETUP_STREAM(uart_putchar, NULL, _FDEV_SETUP_WRITE);
#define LED PB5
void delayms( uint16_t millis ) { //approximate 1 millisecond delay
while ( millis ) {
_delay_ms( 1 );
millis--;
}
}
// ---------------------------------------------------------------------------
// I2C (TWI) ROUTINES
//
// The standard clock rate is 100 KHz, and set by I2C_Init
#define F_SCL 100000L // I2C clock speed 100 KHz
#define READBIT 1 //low bit of device address for read
#define TW_START 0xA4 // send start condition (TWINT,TWSTA,TWEN)
#define TW_STOP 0x94 // send stop condition (TWINT,TWSTO,TWEN)
#define TW_ACK 0xC4 // return ACK to slave
#define TW_NACK 0x84 // return NACK to slave
#define TW_SEND 0x84 // send data (TWINT,TWEN)
#define TW_READY (TWCR & 0x80) // ready when TWINT returns to logic 1.
#define TW_STATUS (TWSR & 0xF8) // returns value of status register
// LPS25H register definitions
#define LPS25H 0xBA //8-bit device address with SA0 high as per Pololu breakout
#define STATUS 0x27
#define P_OUT_L 0x28
#define T_OUT_L 0x2B
#define CTRL_REG1 0x20
#define CTRL_REG2 0x21
#define CONFIG 0x10
#define ID 0x0F
void I2C_Init(){
// at 16 MHz, the SCL frequency will be 16/(16+2(TWBR)), assuming prescalar of 0.
// so for 100KHz SCL, TWBR = ((F_CPU/F_SCL)-16)/2 = ((16/0.1)-16)/2 = 72
TWSR = 0; // prescalar to zero
TWBR = ((F_CPU/F_SCL)-16)/2; // set SCL frequency in TWI bit register
}
void I2C_Stop(void) {
TWCR=TW_STOP;
// wait for stop condition to be executed on bus
// TWINT is not set after a stop condition!
while(TWCR & _BV(TWSTO));
}
unsigned char I2C_Detect(unsigned char addr){
// look for device at specified address; return 1=found, 0=not found
TWCR = TW_START; // send start condition
while (!TW_READY); //wait
TWDR = addr; // load device's bus address
TWCR = TW_SEND; // and send it
while (!TW_READY);
return (TW_STATUS==0x18); // return 1 if found; 0 otherwise
}
void ShowDevices(void){
// search all 127 addresses, report those present on the I2C bus
for (unsigned char addr=1; addr<128; addr++) {
if (I2C_Detect(addr<<1)) // I2C detected?
printf(" .%02X",addr<<1);
I2C_Stop();
}
}
void I2C_Start (unsigned char slaveAddr) {
I2C_Detect(slaveAddr);
}
unsigned char I2C_Write (unsigned char data) {
// sends a byte to slave
TWDR = data; // load data to be sent
TWCR = TW_SEND; // and send it
while (!TW_READY); // wait
return (TW_STATUS!=0x28); //0 if successful, 1 if not
}
unsigned char I2C_ReadACK () {
// reads a byte from slave
TWCR = TW_ACK; // ack = will read more data
while (!TW_READY); // wait
return TWDR;
//return (TW_STATUS!=0x28);
}
unsigned char I2C_ReadNACK () {
// reads a byte from slave
TWCR = TW_NACK; // nack = not reading more data
while (!TW_READY); // wait
return TWDR;
//return (TW_STATUS!=0x28);
}
void I2C_WriteByte (unsigned char busAddr, unsigned char data) {
// write byte to slave
I2C_Start(busAddr); // send bus address
I2C_Write(data); // then send the byte
I2C_Stop();
}
void I2C_WriteRegister(unsigned char busAddr, unsigned char deviceRegister, unsigned char data){
I2C_Start(busAddr); // send bus address
I2C_Write(deviceRegister); // first unsigned char = device register address
I2C_Write(data); // second unsigned char = data for device register
I2C_Stop();
}
unsigned char I2C_ReadRegister(unsigned char busAddr, unsigned char deviceRegister) {
// read single byte of data in register
unsigned char data = 0;
I2C_Start(busAddr); // send device address
I2C_Write(deviceRegister); // set register pointer
I2C_Start(busAddr+READBIT); // restart as a read operation
data = I2C_ReadNACK(); // read the register data
I2C_Stop(); // stop
return data;
}
// Read a two-byte word, low order first
signed int I2C_ReadTempRaw(unsigned char busAddr, unsigned char deviceRegister) {
unsigned int data = 0;
unsigned char l;
I2C_Start(busAddr); // send device address
I2C_Write(deviceRegister | 0x80); // set register pointer, autoincrement
I2C_Start(busAddr+READBIT); // restart as a read operation
l = I2C_ReadACK(); // read the register data
data |= I2C_ReadNACK(); //read next unsigned char
I2C_Stop(); // stop
return (signed int) ((data<<8)|l);
}
// read a 3 byte value, lowest order byte first
signed long I2C_ReadPressureRaw(unsigned char busAddr, unsigned char deviceRegister) {
unsigned char pxl,pl,ph;
I2C_Start(busAddr); // send device address
I2C_Write(deviceRegister | 0x80); // set register pointer, autoincrement
I2C_Start(busAddr+READBIT); // restart as a read operation
pxl = I2C_ReadACK(); // read ls byte
pl = I2C_ReadACK(); // read middle
ph = I2C_ReadNACK(); // read high
I2C_Stop(); // stop
return (int32_t)ph << 16 | (uint16_t)pl << 8 | pxl;
}
int main( void ) {
unsigned char id;
long p;
int t;
double pp,tt;
DDRB |= (1 << LED);// set LED pin to output
uart_init(9600);
stdout = &mystdout; //Required for printf init
printf("Init I2C\r\n");
I2C_Init();
printf("Showing all I2C devices attached");
ShowDevices();
printf("\r\ndone\r\n");
id=I2C_ReadRegister(LPS25H,ID); //check internal device ID
printf("LPS25H Device Id= %02x\r\n",id);
// recommended one-shot operation (see AN4450 from ST)
I2C_WriteRegister(LPS25H,CONFIG,0x0f); //set to maximum averaging
id=I2C_ReadRegister(LPS25H,CONFIG); //read back configuration
printf("Config= %02x\r\n",id);
while(1) {
I2C_WriteRegister(LPS25H,CTRL_REG1,0x84); //power up, one shot mode, BDU=1
I2C_WriteRegister(LPS25H,CTRL_REG2,1); //initiate measurement
while(I2C_ReadRegister(LPS25H,CTRL_REG2)); //wait till done
p = I2C_ReadPressureRaw(LPS25H,P_OUT_L);
pp = p /4096.; // sensitivity = 4096 LSB per hPa
t = I2C_ReadTempRaw(LPS25H,T_OUT_L);
tt = t/480. + 42.5; //sensitivity = 480 LSB per degree C
printf("pt: %8.3f, %5.2f\r\n",pp,tt);
}
I2C_WriteRegister(LPS25H,CTRL_REG1,0x00); //power down reset
delayms(200); //give it a rest!
}[/syntax]
Chcę przeportować tylko obsługę czujnika, strumienie 'stdout' nie są mi potrzebne gdyż wynik pomiaru przesyłam sobie za pomocą nrf24l01 do centrali i potem do komputera. Oto, co napisałem i nie działa:
[syntax=c]// pomiar ciśnienia *****************************
// uint8_t sendBufferLPS[] = {CONFIG_LPS,0x0f,CTRL_REG1,0x84,CTRL_REG2, 0x01, P_OUT_L | 80,CTRL_REG1,0x00};
// konfiguracja czujnika
TWI_MasterWriteRead(&twiMaster,
SLAVE_ADDRESS,
&sendBufferLPS[0],
2,
0);
while ((twiMaster.status != TWIM_STATUS_READY) && (spiTimeout > 0)) {
spiTimeout--;
}
if (spiTimeout == 0)
{
//MASTER.STATUS = TWI_MASTER_BUSSTATE_IDLE_gc;
TWIE_MASTER_STATUS &= ~(1<<TWI_MASTER_BUSSTATE1_bp);
TWIE_MASTER_STATUS |= (1<<TWI_MASTER_BUSSTATE0_bp);
}
spiTimeout = 1000000000000;
// włączenie czujnika i rozpoczęcie pomiaru
TWI_MasterWriteRead(&twiMaster,
SLAVE_ADDRESS,
&sendBufferLPS[2],
4,
0);
while ((twiMaster.status != TWIM_STATUS_READY) && (spiTimeout > 0)) {
spiTimeout--;
}
if (spiTimeout == 0)
{
//MASTER.STATUS = TWI_MASTER_BUSSTATE_IDLE_gc;
TWIE_MASTER_STATUS &= ~(1<<TWI_MASTER_BUSSTATE1_bp);
TWIE_MASTER_STATUS |= (1<<TWI_MASTER_BUSSTATE0_bp);
}
// odczekanie na zakończenie pomiaru
TWI_MasterWriteRead(&twiMaster,
SLAVE_ADDRESS,
&sendBufferLPS[4],
1,
1);
while ((twiMaster.status != TWIM_STATUS_READY) && (spiTimeout > 0)) {
spiTimeout--;
}
if (spiTimeout == 0)
{
//MASTER.STATUS = TWI_MASTER_BUSSTATE_IDLE_gc;
TWIE_MASTER_STATUS &= ~(1<<TWI_MASTER_BUSSTATE1_bp);
TWIE_MASTER_STATUS |= (1<<TWI_MASTER_BUSSTATE0_bp);
}
// odczytanie pomiaru
TWI_MasterWriteRead(&twiMaster,
SLAVE_ADDRESS,
&sendBufferLPS[6],
1,
3);
while ((twiMaster.status != TWIM_STATUS_READY) && (spiTimeout > 0)) {
spiTimeout--;
}
if (spiTimeout == 0)
{
//MASTER.STATUS = TWI_MASTER_BUSSTATE_IDLE_gc;
TWIE_MASTER_STATUS &= ~(1<<TWI_MASTER_BUSSTATE1_bp);
TWIE_MASTER_STATUS |= (1<<TWI_MASTER_BUSSTATE0_bp);
}
tempBuffer[9] = twiMaster.readData[0];
tempBuffer[10] = twiMaster.readData[1];
tempBuffer[11] = twiMaster.readData[2];[/syntax]
Wydaje mi się, że źle mam przepisany fragment pt.: "odczekanie na zakończenie pomiaru", ale nie mam pomysłu jak inaczej to zrobić. W załączniku przesyłam DS czujnika oraz bibliotekę do obslugi I2C (to biblioteka atmela bez żadnych zmian z mojej strony).
Proszę uprzejmie o wskazówki i podrawiam.Statystyki: Napisane przez dawid75_75 — 31 paź 2016, o 14:47
]]>