Posts: 1
Registered: ‎04-19-2016

CP2104 No Response on GPIO.2 for RS485

Hello, I am trying to get the CP2104 to work with an RS485 transciever we are using. I have programmed the GPIO as shown in the capture attached but get nothing on the output of GPIO.2 when transmitting. I used AN721 to program the configuration and ensured that the capacitors on Vpp are 4.7uF, the configure is also read back by the customization utility as what was programmed but still the logic analyzer shows no response from GPIO.2. The serial communications work fine so I dont believe the chip is broken I am just surprised that the extra functionality does not work at all.


Can anyone see what I have done wrong here or has anyone actually gotten a CP2014 to work with RS485 flow control? I would rather try and figure out what is going on before redesigning the board with a different interface on the assumption that the CP2104 can not actually use its GPIO pins.


Thank you,




Posts: 2,308
Registered: ‎10-14-2014

Re: CP2104 No Response on GPIO.2 for RS485