I have made a device which, at the moment, is essentially a 328 with an LED on pin15 ( but is called Arduino pin 9 ). I burned a bootloader into it, using a commercial UNO as the ISP, and then transferred it to its standalone board. Rx and TX are connected to a USB-UART module ( uses the CP2102 ) I got on Ebay and which seems to be OK because it is recognised by the pc. I also connected the GND and RST pins. I have tried to upload the basic 'Blink' sketch to the 328 using the Arduio IDE, but without success. In fact I've tried all sorts of things, including changing the name of the board and the name of the programmer ) All I ever get is a message saying there is a ' sync error 0X00', IIRC. I thought you could upload sketches to a standalone board using the Arduino IDE via the serial Rx and Tx pins provided the chip had a bootloader. Does anyone know what the mistake is?