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USB Superspeed Peripherals

xigu_1705831
New Contributor II

1. our purpose to generate following i2c sequence:
     START-0xDA-0x33-0x05-0x00-0x00-0x00-0xa1-0x00-0x80-0x01-0x01-0xa2-restart-0xDB-(read)0x33-0x41-0x02.....0x78-STOP
2. we are trying to use CyU3PI2cTransmitBytes API. but Preamble Values more than 8 bytes are not supported.

3. we are also try CyU3PI2cTransmitBytes + CyU3PI2cTransmitBytes to generate the sequence. the signal between these APIs is stop-start not restart. 
        START-0xDA-0x33-0x05-0x00-0x00-0x00-0xa1-0x00-0x80-0x01-0x01-0xa2-stop-start-0xDB-(read)0x33-0x41-0x02.....0x78-STOP

     our i2c slave device not support it.
4. from the following link, seems fx2 also have this issue. and there is an workarround. can you help check our fx3 can also take this method and how to do?
CY7C68013A I2C repeated start condition.

thanks
xingxing

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5 Replies
YiZ_31
Moderator
Moderator

Hi,

Have you tried CyFx3BootI2cSendCommand ?

Regards,
Eddie

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xigu_1705831
New Contributor II

hi Eddie,
     can you help clarify how to use CyFx3BootI2cSendCommand? the preamble parameter also is limitted to 8 bytes. this is same with CyU3PI2cTransmitBytes. from api document the CyU3PI2cTransmitBytes will also use CyU3PI2cSendCommand. is there any difference between these two APIs?


thanks
xingxing

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xigu_1705831
New Contributor II

hi Eddie,
i just tried sample code: EZ-USB FX3 SDK\1.3\firmware\serialif_examples\cyfxusbi2sdmamode

still cannot access our i2c device.
thanks
xingxing

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YiZ_31
Moderator
Moderator

Hi Xingxing,

Our engineer has already explained to you that your i2c slave cannot be supported in another thread. Preamble longer than 8 bytes cannot be supported by FX3.

Re: i2c long reigster address read/write

Regards,

Eddie

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xigu_1705831
New Contributor II

hi Eddie,
     yes, i have told our custmor about that. but seems there is an workarround on fx2 in the link:  CY7C68013A I2C repeated start condition.
     i just want double confirm if fx3 has similar solution.

thanks
xingxing

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