I want to program the PIC directly from the serial port.

[RobertD]

Hi there folks. I'm having problem with my firefly/junebug combo, and I need to program my 16F88, so I'm thinking of using the serial port with four wires to the chip. I have read that you can do in circuit programming. I just want to know which pins to use for that. Off hand, I'd say Vdd,Vss,RB3/PGM, and RB2/DT.

I also use MPLab, there is a port selection so I can use the serial output of my computer to program my chip.

Can anyone help me with that...?

 

[blueroomelectronics]

Try this first, it'll bypass the BS250 and should work fine.
**broken link removed**

PS if you bring your unit to Creatron next time you're in Toronto contact me first and I'll repair it on the spot.

 

[RobertD]

Thanks, I did put the jumper, and got life from the firefly. Even programmed my 16F88 once successfully. But I tried to change the pinout prog, and that didn't work, so I tried another programmer, the MPlab PM3, and it started writing stuff on the screen, so I shut down MPlab with the task manager, and now I don't get power to the firefly, nor does pickit read the chip anymore, it seems like I killed the app... :~(

I just found out my pic change worked, so I changed programmer for nothing, it was working fine, and caused myself trouble for nothing. Now I still don't get power to the firefly, probably because MPlab PM3 did some damage when I shut it off while it was running.

 

[blueroomelectronics]

If the Junebugs Target LED (two circles) is OFF that means external VDD is powered. Of course the jumper solution above makes the BS250 moot.
You can use the PICKit2 2.51 software to erase PICs and control VDD if MPLAB is unhappy about the target PIC (this can happen if you program an alien .hex file to a PIC it can render it's ID data useless)