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器件型号：MSPM0C1104 工具与软件：
我在 MSPM0C1104 EVB 上开发软件代码。
现在、我们需要从 I2C 从器件中读取寄存器内容。
而不是规格。 I2C 器件的读取时序是多少
此器件的读取流程为：
I2C_START、Slave_Addr + W、Reg_Addr、
I2C_START、 DATA+R、Slave_Addr、Data1、Data2、Data3、 DATA4、I2C_STOP。
我使用并从示例代码"C：\ti\mspm0_sdk_2_03_00_07\examples\nortos\LP_MSPM0C1104\driverlib\i2c_controller_rw_multibyte_fifo_polar"中修改。
#include "ti_msp_dl_config.h"
/*
* Number of bytes to send from Controller to target.
* This example uses FIFO with polling, and the maximum FIFO size is 4.
* Refer to interrupt examples to handle larger packets
*/
#define I2C_TX_PACKET_SIZE (3)
/*
* Number of bytes to received from target.
* This example uses FIFO with polling, and the maximum FIFO size is 4.
* Refer to interrupt examples to handle larger packets
*/
#define I2C_RX_PACKET_SIZE (3)
/* Data sent to the Target */
uint8_t gTxPacket[I2C_TX_PACKET_SIZE] = {0x00, 0x61, 0x00};
/* Read Register Address*/
uint8_t gRegisterAddr[2] = {0x10, 0x14};
/* Data received from Target */
volatile uint8_t gRxPacket[I2C_RX_PACKET_SIZE];
/* I2C Target address */
#define I2C_TARGET_ADDRESS (0x29)
int main(void)
{
SYSCFG_DL_init();
/* Set LED to indicate start of transfer */
DL_GPIO_setPins(GPIO_LEDS_PORT, GPIO_LEDS_USER_LED_1_PIN);
/*
* Fill FIFO with data. This example will send a MAX of 4 bytes since it
* doesn't handle the case where FIFO is full
*/
DL_I2C_fillControllerTXFIFO(I2C_INST, &gTxPacket[0], I2C_TX_PACKET_SIZE);
/* Wait for I2C to be Idle */
while (!(
DL_I2C_getControllerStatus(I2C_INST) & DL_I2C_CONTROLLER_STATUS_IDLE))
;
/* Send the packet to the controller.
* This function will send Start + Stop automatically.
*/
DL_I2C_startControllerTransfer(I2C_INST, I2C_TARGET_ADDRESS,
DL_I2C_CONTROLLER_DIRECTION_TX, I2C_TX_PACKET_SIZE);
/* Poll until the Controller writes all bytes */
while (DL_I2C_getControllerStatus(I2C_INST) &
DL_I2C_CONTROLLER_STATUS_BUSY_BUS)
;
/* Trap if there was an error */
if (DL_I2C_getControllerStatus(I2C_INST) &
DL_I2C_CONTROLLER_STATUS_ERROR) {
/* LED will remain high if there is an error */
__BKPT(0);
}
/* Wait for I2C to be Idle */
while (!(
DL_I2C_getControllerStatus(I2C_INST) & DL_I2C_CONTROLLER_STATUS_IDLE))
;
/* Add delay between transfers */
delay_cycles(1000);
/* Send a read request to Target */
DL_I2C_startControllerTransfer(I2C_INST, I2C_TARGET_ADDRESS,
DL_I2C_CONTROLLER_DIRECTION_RX, I2C_RX_PACKET_SIZE);
/*
* Receive all bytes from target. LED will remain high if not all bytes
* are received
*/
for (uint8_t i = 0; i < I2C_RX_PACKET_SIZE; i++) {
while (DL_I2C_isControllerRXFIFOEmpty(I2C_INST))
;
gRxPacket[i] = DL_I2C_receiveControllerData(I2C_INST);
}
// Test: read target register data
/* 1: Do Dummy Write */
DL_I2C_fillControllerTXFIFO(I2C_INST, &gRegisterAddr[0], 1);
// Wait for I2C to be Idle */
while (!(
DL_I2C_getControllerStatus(I2C_INST) & DL_I2C_CONTROLLER_STATUS_IDLE))
;
// Transfer register address w/o i2c_STOP
DL_I2C_startControllerTransferAdvanced(I2C_INST, I2C_TARGET_ADDRESS, DL_I2C_CONTROLLER_DIRECTION_TX,\
1, DL_I2C_CONTROLLER_START_ENABLE, DL_I2C_CONTROLLER_STOP_DISABLE, DL_I2C_CONTROLLER_ACK_ENABLE);
// wait Poll until the Controller writes all bytes */
while (DL_I2C_getControllerStatus(I2C_INST) &
DL_I2C_CONTROLLER_STATUS_BUSY_BUS)
;
/* 2: Read data */
/* Wait for I2C to be Idle */
while (!(
DL_I2C_getControllerStatus(I2C_INST) & DL_I2C_CONTROLLER_STATUS_IDLE))
;
/* Add delay between transfers */
delay_cycles(1000);
/* Send a read request to Target */
//DL_I2C_startControllerTransfer(I2C_INST, I2C_TARGET_ADDRESS,
// DL_I2C_CONTROLLER_DIRECTION_RX, I2C_RX_PACKET_SIZE);
DL_I2C_startControllerTransferAdvanced(I2C_INST, I2C_TARGET_ADDRESS, DL_I2C_CONTROLLER_DIRECTION_RX,\
I2C_RX_PACKET_SIZE, DL_I2C_CONTROLLER_START_ENABLE, DL_I2C_CONTROLLER_STOP_ENABLE, DL_I2C_CONTROLLER_ACK_DISABLE);
/*
* Receive all bytes from target. LED will remain high if not all bytes
* are received
*/
for (uint8_t i = 0; i < I2C_RX_PACKET_SIZE; i++) {
while (DL_I2C_isControllerRXFIFOEmpty(I2C_INST))
;
gRxPacket[i] = DL_I2C_receiveControllerData(I2C_INST);
}
/* If write and read were successful, toggle LED */
while (1) {
DL_GPIO_togglePins(GPIO_LEDS_PORT,
GPIO_LEDS_USER_LED_1_PIN | GPIO_LEDS_USER_TEST_PIN);
delay_cycles(12000000);
}
}
在主函数中、我在最后一个 while 循环之前添加该读取函数。
遗憾的是、程序在 I2C 读取中停止、因为 SCK 保持低电平
有人能解决这个问题吗？ 谢谢
