Can the problem be that i'm using atmega1284 instead of atmega1284p?
If you're ....
a. 100% certain the bootloader was installed properly, which isn't always obvious
to have occurred, and
b. your comms h.w. is 100%, and
c. you properly tapped into the DTR signal on the comm link [???] to reset the
d. you properly changed the signature back and forth between burning the
bootloader and uploading sketches, and
e. your board is well designed with good v.regs and lots of bypass caps,
Then, maybe it's related to the 1284 vs 1284P chips. What lefty mentioned
should fix the 1284P RXD/crystal sensitivity problem, but some people had to
put low-pass filters on the RXD line, eg 1-5K series-R and 100 pF to gnd at
You should only need a pullup on RXD if the pin is floating in operation, such as
FTDI cable or MAX232 being disconnected.
Re item c, how is one certain that the MAX232 circuit DTR pin will properly
trigger the Arduino Reset? Probably best to measure it. From what I measured,
DTR at the 0.1 uF cap goes low [5V -> 0V] for the duration of sketch uploading.