I'm here again I've been reading a lot so I have more information now.

But I Tried this first I downlodea FLIP ok I have my cable with MAX233A so my TXD and RXD of th uc are connected to the serial port of the PC also I have PSEN to a grounded switch sso I can Connected and disconnected from ground, I still missing something..

This is what I did first power to the PCB second I press my manual reset while holding the reset I switched PSEN to ground (have to be disconnected at power up)then I released the reset ( holded for 2 seconds there is not an specific time on the data sheet from ATMEL)after that, I disconnect PSEN from ground, on a second try I repeated all but left PSEN connected to ground my PCB has a display I show my software version there at power up to know if a get reprogram a load a diferent version number.

So my uc has been parallel program before I'm trying to reprogram with the UART.

Now after the procedure I described the uc should be at the bootloader.
I'm forcing by hardware this condition but when I try FLIP I get this error TIMEOUT ERROR

I tried all diferent baud rates and the same happens I'm working with 11.059 crystal so it should be good for 9600 or 19.2k baud
So what I'm missing?