Posted on May 17, 2011 at 12:34Hello,
I'm using the um0427 library, and after a stop the SCL is at the high level, but the SDA not go back to high level,
On the scope trace we can also see the glitchs already evoked (http://www.st.com/mcu/forums-cat-6701-23.html)
gpio/i2c config
*******
/* Configure I2C1 pins: SCL and SDA ------*/
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_OD;
GPIO_Init(GPIOB, &GPIO_InitStructure);
/* I2C1 configuration ---*/
I2C_DeInit(I2C1);
I2C_InitStructure_1wire.I2C_Mode = I2C_Mode_I2C;
I2C_InitStructure_1wire.I2C_DutyCycle = I2C_DutyCycle_2;
I2C_InitStructure_1wire.I2C_OwnAddress1 = I2C1_SLAVE_ADDRESS7;
I2C_InitStructure_1wire.I2C_Ack = I2C_Ack_Enable;
I2C_InitStructure_1wire.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
I2C_InitStructure_1wire.I2C_ClockSpeed = 50000;
I2C_Init(I2C1, &I2C_InitStructure_1wire);
/*---------------*/
code
*************************
void resetds2482(void){
/* Send I2C1 START condition */
I2C_GenerateSTART(I2C1, ENABLE);
/* Test on I2C1 EV5 and clear it */
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT));
I2C_Send7bitAddress(I2C1, DS2482, I2C_Direction_Transmitter);
/* Test on I2C1 EV6 and clear it */
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
/* Envoi du Reset */
I2C_SendData(I2C1, DRST);
/* Test on I2C1 EV8 and clear it */
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
/*Si la commande a réeussi le 2482 répond par un octet on Restrart l'I2C en Reception*/
I2C_GenerateSTART(I2C1, ENABLE);
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT));
I2C_Send7bitAddress(I2C1, DS2482, I2C_Direction_Receiver);
/* Test on EV6 and clear it */
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED));
/*Recuperation du Status Registger ---*/
regvalue = I2C_ReceiveData(I2C1);
while(I2C_GetFlagStatus(I2C1, I2C_FLAG_RXNE));
/* Send I2C1 STOP Condition */
I2C_GenerateSTOP(I2C1, ENABLE);
GPIOB->BSRR = GPIO_Pin_7;
myDelay(80000);
}
[ This message was edited by: julien.massot on 06-05-2008 12:24 ]
[ This message was edited by: julien.massot on 06-05-2008 12:26 ]
