我正在尝试通过 I2C 与TM4C123GXL Launchpad的Pololu MinIMU9v2进行通信,但每次我尝试写入总线时,我都会收到I2C_MASTER_ERR_ADDR_ACK和I2C_MASTER_ERR_DATA_ACK。打印出从地址表明它看起来是正确的,所以我想这可能是我在使用 TI Launchpad 驱动程序库时做错了。
这是初始化例程:
void
InitI2CBus(void)
{
// Initialize the TM4C I2C hardware for I2C0
SysCtlClockSet(SYSCTL_SYSDIV_1 | SYSCTL_USE_OSC | SYSCTL_OSC_MAIN |
SYSCTL_XTAL_16MHZ);
SysCtlPeripheralEnable(SYSCTL_PERIPH_I2C0);
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOB);
GPIOPinConfigure(GPIO_PB2_I2C0SCL);
GPIOPinConfigure(GPIO_PB3_I2C0SDA);
GPIOPinTypeI2C(GPIO_PORTB_BASE, GPIO_PIN_3);
// Initialize the bus
I2CMasterInitExpClk(I2C0_BASE, SysCtlClockGet(), false);
}
以下是尝试从设备读取字节的代码:
uint8_t
ReadByte(uint8_t slaveAddr, uint8_t subAddr)
{
// Write SUB
slaveAddr |= 1; // Set LSB to writemode
I2CMasterSlaveAddrSet(I2C0_BASE, slaveAddr, false);
I2CMasterDataPut(I2C0_BASE, subAddr);
I2CMasterControl(I2C0_BASE, I2C_MASTER_CMD_SINGLE_SEND);
while(I2CMasterBusy(I2C0_BASE)) { }
if (CheckError())
{
return 0;
}
// Read data
slaveAddr &= ~1; // Set LSB to readmode
I2CMasterSlaveAddrSet(I2C0_BASE, slaveAddr, true);
I2CMasterControl(I2C0_BASE, I2C_MASTER_CMD_SINGLE_RECEIVE);
while(I2CMasterBusy(I2C0_BASE)) { }
I2CMasterControl(I2C0_BASE, I2C_MASTER_CMD_SINGLE_RECEIVE);
while(I2CMasterBusy(I2C0_BASE)) { }
uint8_t response = I2CMasterDataGet(I2C0_BASE);
if (CheckError())
{
return 0;
}
return response;
}
有什么想法我可能做错了吗?