Hi everyone !

I spent hours on this bootloader and didn't understand anything.
My hardware :
-pic16f877a quartz=8MHz.
-development card with a FTDI USB-serial interface.
-2 programmers (LVP and HVP respectively Schaer and JDM type)
-2 computers... what else ?

Software :
-picbootplus
-icprog
-mplab (of course)
-bootloader 2.81

What I'm doing : I modified the bootloader code to fit my hardware
configuration : frequency and baud rate adjusted.
I loaded the bootloader in the PIC, start picbootplus, load a hex
file, click on Write and reset the PIC... nothing happened !!

I saw it working for some hours, but since it doesn't work I changed
PIC, programmer, PC, verified serial communication : all OK !
What's wrong ??

Please help me.
Romain