STM32F1xx smbus send address no ack?

[Jseyn.1]

my smbus device is a temperature sensor (TMP100).MCU is STM32F103RBT6

when i wrote a word to slave as following:

I2C_GenerateSTART(SMBus_NAME, ENABLE);

while(!I2C_CheckEvent(I2C2,I2C_

I2C_Send7bitAddress(SMBus_NAME, slaveAddr, I2C_Direction_Transmitter);

while(!I2C_CheckEvent(I2C2,I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED)){;}

I2C_SendData(I2C2,addr);// device registor address

the registor I2C2->SR1 : 0x4400. due to the smbus line nack.. how to solve it?

[Bubbles]

Hi, what is the configured bus speed?

Do you have a scope to observe the SMBUS line?

The nack can be anything, best if you can use a scope or at least logic analyzer to observe.

BR,

J

[TDK]

If the slave does not ACK, there is likely a hardware issue and/or you are using the incorrect slave address. Your code doesn't contain enough information to determine the latter. Note that slave addresses should be left-aligned.

[Tesla DeLorean]

https://www.ti.com/lit/ds/symlink/tmp100.pdf?ts=1641822742177

Slave Address (Table 2)

1001000 -> 0x90

1001001 -> 0x92

1001010 -> 0x94

[Jseyn.1]

I recheck my slave address 0x48, as TDK said the slave address left-aligned(0x90). smbus clock is 100khz. I2C_SendData(I2C2,addr) failed, the smbdata line sholud be low,but no changes.

[Jseyn.1]

hi ,

about the SMBus Alert response , gotta dizzy. could u tell the timing? as the smbhost send 0x18 or 0x19 gotta no ack

 

[Jseyn.1]

Hey,

Thankyou for the slience, i gotta it.

smhost to request the slave addres & status when the alert pin active.