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USB low-full-high speed peripherals Forum Discussions

romac_285831
Level 2
Level 2

I’m having some trouble with the cypress 65215A chip. If I program it to be in I2C mode on SCB0, either master or slave, the 215A will hold the SDA and SCL lines low until a USB cable is connected between the board and a PC, and then the cypress will release these lines. You can then remove the USB connection, and the 215A still lets the I2C lines float.

I have found that programming the cypress into UART mode prevents this problem – the 215A won’t hold the I2C lines (pins 28 and 29) low.

Do you have any idea what’s going on?

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1 Solution

Hello

Please disable the 1.8 V regulator using the USB-Serial configuration utility as the VDDD input voltage is less than 2V.

Best Regards

Yatheesh

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3 Replies
YatheeshD_36
Moderator
Moderator
Moderator
750 replies posted 500 replies posted 250 solutions authored

Hello

Can you please share the schematics. Are you seeing the same behavior when Pull ups are connected to the I2C lines and are you connecting any slave devices?

Best Regards

Yatheesh

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Hi,

i2c lines are stuck low they cannot be pulled up. CY7C65215 chip works well but  CY7C65215A shows this problem.

CY7C65215 chip has other bugs in i2c. Why difference in behaviour of these chips.

Capture.PNG

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Hello

Please disable the 1.8 V regulator using the USB-Serial configuration utility as the VDDD input voltage is less than 2V.

Best Regards

Yatheesh

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