You can only program a pic via serial if you load a bootloader....
To program a pic you need to use PGC, PGD, MCLR Vdd and Vss.... Via a pickit2/3 or home made hardware.... Using software to suit the design..
The MCLR is HVP ( high voltage programming pin) this is the one that needs 12.5v+ whilst programming... Look at the circuit I showed you.
The other option is to use Nigel's hardware ( in my tutorial ). I don't think Nigel's maintains the software anymore but I'm pretty sure it does the pic16f877a
in nigel's P16Pro40 what kind of connector that he use? Sub-D 9 pin or USB type A?
for the link that u give i cant find that transistor model number in my country BC557, IC that look like comparator( i do not know the model ), 74LS06 and 4013 cant find either...
what i prefer is 1 usb to power the PIC and can also program... i make RS232 programmer board because i thought it the basic but it harder than what i think...