Standalone ATMega328 with OPTIBOOT

I FINALLYgot 4 ATMega328s; 2 with bootloader OPTIBOOT ( UNO ).
That´s what the sticker ( label ) says.
Can I build this ( Standalone Assembly.hmt ) to upload sketches? With v0022?
Does the serial connector go directly to the COM port or do I still need an USB-Serial cable?
I suupose so because You can´t connect more than 5v to an TTL IC.
I got a cable which uses PL2303 IC. Didn´t work.
Strangely when I power the circuit the LED starts flashing, the frecuency goes higher
until the LED goes off and does nothing more, even after resetting.
I also found this circuit on the web.
I can get a MAX232 locally. I suppose I should connect pins 2, 3 and 5 to the COM port. Do I have to invert the signals?
Do I have to edit PREFERENCES, BOARD, PROGRAMMERS.txt? Should it work?
Please don´t tell me to buy an Arduino.
The UNO here costs Bs.550.00. Divide that by 4.3; that´s the price in $US. Thanks,

MAX232 circuit.jpg

serial standalone.jpg

I FINALLYgot 4 ATMega328s; 2 with bootloader OPTIBOOT ( UNO ). That´s what the sticker ( label ) says. Can I build this ( Standalone Assembly.hmt ) to upload sketches? With v0022?

Yes, just be sure to select Uno for the board selection choise before uploading.

Does the serial connector go directly to the COM port or do I still need an USB-Serial cable? I suupose so because You can´t connect more than 5v to an TTL IC.

RS-232 comm ports will not work directly wired to arduino serial pins, as the voltage will damage the chip.

I got a cable which uses PL2303 IC. Didn´t work.

Most such USB cables don't include the DTR signal needed to facilate the auto-reset function on the arduino board, so uploading won't work automatically, you must use the manual reset button and release it at just the correct moment after hitting upload in the IDE.

Strangely when I power the circuit the LED starts flashing, the frecuency goes higher until the LED goes off and does nothing more, even after resetting. I also found this circuit on the web. I can get a MAX232 locally. I suppose I should connect pins 2, 3 and 5 to the COM port. Do I have to invert the signals?

The MAX232 handles the inverting automatically. However you must also wire in the comm port DTR signal through the MAX232 to enable the auto-reset function.

Do I have to edit PREFERENCES, BOARD, PROGRAMMERS.txt? Should it work?

No changes required, the Arduino IDE will just think it's talking to a Uno board as long as you select that board and select the proper comm port number.

Please don´t tell me to buy an Arduino. The UNO here costs Bs.550.00. Divide that by 4.3; that´s the price in $US. Thanks,

Check your reset wiring - looks like your switch grounds the output of your regulator. The switch should go to pin 1, and pin1 should a resister going to +5V. See any arduino schematic in the hardware section, if you access to DTR than wire that in with a 100nf (0.1uF) capacitor for autoreset as retrolefty says.

The LED flashing faster & faster, that's usually a sign your bootloader is loaded and running a simple sketch. Odd that it only runs 1 time tho - the proloaded ICs I bought last winter would just start the slow blinking again after a couple of seconds.

CrossRoads: Check your reset wiring - looks like your switch grounds the output of your regulator. The switch should go to pin 1, and pin1 should a resister going to +5V. See any arduino schematic in the hardware section, if you access to DTR than wire that in with a 100nf (0.1uF) capacitor for autoreset as retrolefty says.

The LED flashing faster & faster, that's usually a sign your bootloader is loaded and running a simple sketch. Odd that it only runs 1 time tho - the proloaded ICs I bought last winter would just start the slow blinking again after a couple of seconds.

On the standalone schematic, he has a 7404 driver on RxD. Is that correct?

No, the 7404 is not needed at all with the MAX232. Rx & Tx connect to the MAX232. The MAX232 IO then goes to the connecter, with GND on DB9 Pin 5.

PB5 should only be resister to LED to GND.