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PIC 18F2550 programmer

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Andy G

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Jan 25, 2010
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Hi !
i am building the PicKit2 Lite hardware but first the PIC 18F2550 needs to be programmed with the hex file
Can anyone please let me know what hardware programmer will be best?
Can i use my JDM2 programmer hardware to load its hex file?
do i have to be careful about voltages?

Dear sanjubluerock3,
Can you clarify whether JDM programmer is a Low Voltage Programmer or a normal programmer?
LVP mode programming is not applicable for a PIC 18F2550 which is intended to be used for PicKit2. Pin 26 of the chip is used for the only switch in the PicKit2, which is normally pulled up. Chips programmed in LVP mode cannot use this pin anymore in the circuit as port, it must then be pulled down to avoid entering programming while running.
I am also facing similar problem - how to program the PIC 18F2550 with the PicKit2 firmware.
Please help, I am new to Pic micro, want to make a PicKit2.

do not worry about the voltages, the software will take care of the correct voltages when it is programming the PIC
Use the JDM serial programmer hardware and PicPgm software to load the hex file into the PIC18F2550
you may get the PicPgm software from here
**broken link removed**
To make the pickit2 clone the best circuit is by Palma, it has the zif socket on the pcb
**broken link removed**
you can easily translate into English the web site with
just paste the URL and select Spanish to English
good luck !!
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@tipu electronics
Thanks for your reply.
Not even now I started this project. Your post may help me a lot. I think you also have made your PicKit2 clone in above way. Today I decided to go the way you suggested.
I have already gathered components except the 680 micro-Henry inductance. I don't know where can I find this in Kolkata (Calcutta). Or should I make one over a ferrite dumble from a discarded IF Transformer and measure the inductance with a DMM that have Inductance measuring facility.
I shall write here as I proceed.

@tipu electronics

I have already gathered components except the 680 micro-Henry inductance.


The value is not that critical, mine runs fine on a 470uh.

if you have not yet made the JDM programmer then i would suggest site from where i got the circuit diagram, pcb layout etc
JDM2 based PIC Programmer
however in the circuit the emitter and collector of Q2 needs to be reversed
You do not need to buy 680uH coil, just make one your self
get a color TV IF coil(blue colored) and remove all the windings from it, then wind about 120 turns of 31 SWG enamelled copper wire on the ferrite core ,no need to measure the inductance, it works great !!

Thanks a lot tipu electronics and wp 100 for your prompt response. When It seems that the cause of headache have gone and nothing to worry to reach the end of a project a new cause of headache arises. My latest problem is my motherboard, though it has two com port - one at the back panel, and another inside the motherboard that can be connected with proper cable to the back panel, but I don't know whether it has the voltage capacity to run a JDM programmer. I used both for running other programmers for programming 8051 micro controllers; they have external power source and do not use the port as the power source. The motherboard I use is '5PKPL-AM/PS' by ASUS.
Do you know any method to measure the voltage in different pins of a com port.
Now I am looking JDM2based PIC Programmer @ site

your motherboard has the 9 pin serial port at the back
Just connect the JDM programmer with a serial cable to the computer and the PicPgm software will take care of the voltages

Dear, I know that you are a busy guy, thanks for taking interest in my project. I just measured the voltage between pin 3 and pin 5 of 9-pin D connector com port at the back panel of my PC at its idle condition (PC running, but no PIC programming software is running in the OS). It is 11.11V. Now I am confident about successfully making a JDM programmer around my existing PC.
I read the thread you suggested earlier and now again, but I found nothing regarding idle com port pin voltage. Though it is important for future while I make the JDM and debug it; it contains many active com port voltages and other information. I decided to construct the JDM on a breadboard or on a veroboard (don't want to make a pcb for a single use purpose!). Please suggest the right way. Please take care of my project in future as an experienced forerunner.
Thanks again.

I would suggest you to make a pickit2 clone that too on a pcb etched at home (I made one have a look at Pickit 2 clone in india), its a lot easy to fabricate and trouble shoot, however you do need a working programmer to program 18F2550 first time, If you insist on JDM, I would suggest Multi Pic Programmer Schematic and pcb voltage level you have measured is lot more than enough, I am getting only 6.2 volt from my laptop (JDM not working) and 8.95 Volt after serial port power booster (circuit I made to raise Voltage level, JDM is working with this circuit attached). Please have a look at this link for making a pcb **broken link removed**.
good luck
Happy to help :smile:

Thanks a lot aadhytam,
You have taken lot of interest in my project. I am in a dilemma - which JDM to build? There are many close versions of JDM in the web. One in the suggested by Tipu electronics is good. I found more JDM based programmer in the side column, while looking at the instructible he suggested. Feng3's version is also impressive including his serial port line conditioner required for low voltage com port. So it impressed me most. Above all he has dedicated this programmer for his INDIAn friends, modified this with spares available easily in INDIA. Earlier I once gathered parts to make this one for me, but at that time my motherboard burnt away and I forget about this project. Even 1 : 1 scale print out from my 1020 printer on a magazine paper was also ready. I studied this programmer again today. Find out my old pack of parts, - I shall try to make the pcb in a week, also try to finish the JDM Programmer as early as possible.

I normally make my PCBs in thick glossy magazine paper (glazed newsprint), a thin coat of dextrine glue makes the toner transfer easier. If you are interested I can inform you about the process I follow, but I think you also know this. I heartily welcome Your intention to enrich my project.

Please be patient till I make this project.



I know toner transfer using magazine paper but unable to find dextrose glue or glucose starch, would be grateful if you can provide its common Indian name, I am not expert, in fact I ran my first JDM yesterday, I had started learning PIC recently, Please visit again to get serial port power booster schematic and PCB to boost serial port voltage, I used it to get JDM working on my laptop. It uses 2 Max232 IC's along with 8 capacitors and 5Vdc supply from usb to boost RS232 voltage, I got its idea from Laptop Computer Serial Port Power Booster. What is serial port line conditioner, please provide a link.

Happy independence Day:-D

I know toner transfer using magazine paper but unable to find dextrose glue or glucose starch, would be grateful if you can provide its common Indian name, I am not expert,

Dear aadhyatm,
Do not use inkjet photo paper for printing pcb artwork, use magazine paper (glazed newsprint) that is not heavily printed with color photos, simple text will not make a problem. Try some different magazine sheets, usually above or near 50 gsm will do. You can try supplements that come with special issues of news paper, usually Saturday or, Sunday; try with its cover pages also.

Now prepare the glue. You can purchase Dextrine (gad) from grossery stores, soak it in little water over night. Boil it till it become like paper gum. Cool it. Spread with a paint brush on the magazine paper. Apply a very thin layer. Now dry the paper in bright sunlight till it is extremely dry. One more thing you can use to make the glue is Arraroot, it is also available in the grossery stores, but it is advantageous in that it dissolves radily in the water; boil it till lucidly sticky.

Caution: Don't forget to dry the paper extremely, otherwise it may damage your printer roller, drum or may create paper jam even permanently damage your printer.

I think you know the following steps to make the pcb

You may follow these steps in

Read these attached documents carefully, they helped me a lot.

Hope your success.

Thanks. p55xp

again: I don't know how to post - " Did you find this post helpful? Click: Yes" in my post. Please guide. p55xp


  • Toner transfer paper and pcb.rar
    4.1 MB · Views: 140
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Thanks a lot, Will try this method as soon i get time. Did you find this post helpful? message is automatically added, however one cannot see that in own post.

Today I finished making my Multi Pic Programmer 5V2 PCB in the same procedure I mentioned above.
Thanks, p55xp.

Here it is! from it's component side that is printed too.
Multi PIC Programmer.jpg
Thanks. p55xp

Hallo everyone,
I today build the hardware - WinPic800 detected it as 'unknown' programmer, and PICPgm Programmer auto detected it as JDM Programmer !! LED lights up at the time of detecting it. Up to this it seems that all is correct. I decided to use ICSP connections from the programmer and connect these lines to the pic18f2550 in a breadboard as I have no spare ZIF40 . But what programming software should I use and with what software settings?
Again what to do with Vdd first and Vpp first switch, what this settings actually do in side PIC's programming? Where should I keep the switch while programming pic18f2550. Please suggest, I am very new to pic micro-controller, and want to have a USB programmer (PicKit2) before hand for being actually into it!
Thanks, p55xp.

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