2016年5月5日 · My recent project requires the use of i2c communication using a single master with multiple slaves. I know that with each data byte (actual data) sent by master,the slave responds with Nack\Ack(1,0). I am confused that how this Nack and ACK are interpreted. I searched the web but i didn't got clear picture about this.

A NACK is signaled by an acknowledgement slot in which SDA remains high while SCL cycles under control of the master. Since high is the un-driven state of the pulled-up bus, in the absence of a peripheral at the selected address to positively acknowledge by pulling it down, a NACK condition will passively result.

2020年10月5日 · I am fairly new to I2C so please excuse my lack of knowledge. I am trying to read Data from an PAC1710 sensor using an Stm32H743ZI MCU with the HAL-Library and the cubemx code generator.

2015年7月16日 · I have a question about I2C protocol. I found this on the wikipedia page. "If the transmitter sees a 1 bit (NACK), it learns that: 1) The slave is unable to accept the data. 2) No such slave 3) C...

2023年6月21日 · I need help with I2C communication. The master IC (Arduino Uno) is communicating with a digital potentiometer at address 0101 0000 (only 7 bit 010 1000 in beginTransmission). First I need to send 0000 0000 as the address for the wiper register I want to write to. (Everything up until now works perfectly fine by itself) When I add the second write line Wire.write(byte(res_value)) to write a ...

2022年10月23日 · If it is a read command, data size will be zero } extern void HAL_I2C_SlaveRxCpltCallback(I2C_HandleTypeDef *hi2c){ // This is called after a master 'write' request. first time around it will be a register.

2015年12月31日 · The I2C bus is not a RS-232 serial bus. It is the I2C bus. Suppose one in a million commands can go wrong, then the I2C bus is bad and the hardware has to be fixed. What if the i2c address goes wrong due to a glitch ? or the NACK by the Slave goes wrong, or the Slave sends a ACK and it is received as a NACK.

2013年4月5日 · Start, 0xAA, [Ack], 0x2C, [Ack], Repeated Start, 0xAB, [Ack], Data Read, [Nack], Stop. 0xAA = Fual Gauge Write, 0xAB = Fual Gauge read, 0x2c = SOC reg, Ack= Acknowledge, Nack= No Acknowledge. Technically the I2C address of bq27510 in 7 bit format is 0x55 so when you add the write/read bit then you get in 8 bit format 0xAA and 0xAB respectively.

2015年11月12日 · I have fixed the problem. The problem was occurred because I had 2 master devices that attempt to control the bus at the same time. Hence, it corrupted the message. As written in this link: Master Read "The Aardvark adapter was unable to seize the bus due to the presence of another I2C master. Here, the arbitration was lost during the slave ...

2021年6月18日 · According to the I2C specification, there are five reasons for a NAK: No receiver is present on the bus with the transmitted address so there is no device to respond with an acknowledgment. The receiver is unable to receive or transmit because it is performing some real-time function and is not ready to start communication with the master.