I have a few projects where I want to build a bare bones Arduino into the circuit.
I am having difficulty successfully interacing the CP2104 carrier module with a Atmel 328 Arduino chip having bootloader. The module shows up OK as a virtual port on my Windows
8.1 PC. When I upload a sketch through a USB cable I get the infamous avrdude stk500 sync error. Module to chip connections are Vbus->+5, GND->GND, TX->RX, RX->TX and DTR->Reset via a .1uf cap. The module is powering the chip. I’ve been able to program the chip via ICSP so I know that the chip works. The 328 reset pin is also pulled high and has a push button to ground for reset.
The CP2104 module tested OK by itself on a loopback test but not when hooked up to the 328
Anybody been down this path? Any suggestions?