topic Re: issue for I2C slave using interrupt method on K64F51x in Kinetis Microcontrollers

issue for I2C slave using interrupt method on K64F51x

chhsu0229 — Tue, 14 Jul 2020 16:22:13 GMT

I am working on the I2C master mode and I2C slave mode using edma and interrupt method on K64F MCU.

I connect two k64F devices to test the I2C mode for master and slave.

The master I2C us used the edma to read 5 bytes data on slave address 0x50, subaddress 0x01.

Question 1:

The slave responds the 5 bytes data are 0xF0, 0xF0, 0xF0, 0xF0, and 0xF0.

In fact, the real dates are 0xF0, 0xF0, 0xF0, 0xF0 and 0xB0

It seems the Bit 6 is set as Low Bit on the last bytes and the wave form is shown as below,

Question 2:

Why does the wave form issue plus High signal that mark is read?

Thanks

Re: issue for I2C slave using interrupt method on K64F51x

nxf56274 — Wed, 15 Jul 2020 00:21:01 GMT

Hi,

If the data is 0xF0, 0xF0, 0xF0, 0xF0, and 0x00, will it become 0xF0, 0xF0, 0xF0, 0xF0, and 0x40 ? If so, check your code carefully, the send function may have some problems. What is your sdk, IDE?

Have a great day,
TIC

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Re: issue for I2C slave using interrupt method on K64F51x

chhsu0229 — Wed, 15 Jul 2020 03:11:21 GMT

Hi,

The data is 0x00, 0x00, 0x00, 0x00, and 0x00 and the last byte does not become 0x40.

If the last data is 0x40 and it will become 0x00.

The SDK version that I use is 2.70 and the IDE is MCUX[ressIDE v11.1.1

Thanks

Re: issue for I2C slave using interrupt method on K64F51x

nxf56274 — Thu, 16 Jul 2020 01:14:32 GMT

Hi,

if (g_SlaveDirationFlag == true) //slave send data
{

I2C_SLAVE_BASEADDR->D = 0xF0; //0xFF

g_slaveTxIndex ++;

         if((g_slaveTxIndex -1) == 5)
         {
            /* Switch to receive mode. */
         I2C_SLAVE_BASEADDR->C1 &= ~(I2C_C1_TX_MASK | I2C_C1_TXAK_MASK);

/* Read dummy to release bus. */
I2C_SLAVE_BASEADDR->D;

            g_SlaveDirationFlag = false;
            g_slaveTxIndex = 0;
            }
      }

if((g_slaveTxIndex -1) == 5). This judgement has some problems. It shuold be "if(g_slaveTxIndex == 5) "

Have a great day,
TIC

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