Programming Arduino with a USB to serial converter

Projects Programming
1

Hi all!

Here is the question and a small brief of what I have done up to the moment:

I made a special PCB with ATmega328-PU as controller and I have implemented an ISP connector with all appropriate signals (MISO, MOSI, SCK, RST and power). There is also an ST202 RS232 driver/receiver with a 9pin subconnector with all appropriate signals to the controller (Tx, Rx, RST). I can download the bootloader to this controller by the aim of an Arduino Mega 1280 and everything is OK.

Since I do not have any external programmer for uploading sketches, I thought of doing some programming through the USB to serial converter I have (it is a Prolific USB to serial cable).

When I am trying to upload the sketch to 328, I can see some activity on a SCK LED on the board but at last, I got the message:
"avrdude: stk500_getsync(): not in sync: resp=0x00"

I have chosen through the Arduino IDE menu a 328 board, I double checked the com port, I set Arduino as ISP programmer, but everytime, the message is the same. Any ideas upon this matter would be very much appreciated!

P.S.: The USB to serial converter comes out with #2 pin as RXD/RC, #3 pin as TXD/TC, #4 pin as DTR/TC and #5 as power ground. Respectively, I connect them to #14 pin (Tx1 OUT), #13 pin (Rx1 IN) of ST202 and through a 100n capacitor and a 10K resistor (to VCC) to #1 pin of 328 (RESET).
It is assumed that lines Tx, Rx of 328 (pins #2,3) are connected to ST202 as Tx to #11 pin and Rx to #12 pin.

2

Look at using the 328 pins 2 & 3 (on the chip itself) or pins 0 & 1 on the Arduino as TX & RX. I don't have the pin info in front of me but you can find it in many places. Serial communications for the bootloader is not using SPI, but rather a protcol that is compatable with RS232...