Check the config bits, you might have uploaded something wrong.

Think, if you can program the PIC, it is not fryed !!! LOL You must have done something wrong, check it, its the only way to learn, oh, you might check the cable and the pcb, this programmer is very basic and unstable, try an ICD2 clone ou the Junebug from Blueroom's.

This is my point of view, i could be wrong...

thank u for reply
my configuration word is
__config=0x2128
2128h=10000100101000
bit 13 = 1 ==> CP!=1 ==> code protection off
bit 12 - 9 =0 ==> as per the data sheet
bit 8 = 1 ==> CPD!=1 ==> data memory code protection off
bit 7 = 0 ==> LVP =0 ==> disable low voltage programming
bit 6 = 0 ==> BOREN=0 ==> brownout reset disable
bit 5 = 1 ==> MCLR =1 ==> MCLR use for programing
bit 3 = 1 ==> PWRTE! =1 ==> power on reset off
bit 2 = 0 ==> WDTE=0 ==> watch dog timer off
bit 4,1,0= 0,0,0 ==> FOSC=000 ==> LP crystal oscillator on
what is the wrong with my configuration word
yes this programmer is very basic but i thought it is good to start with it

btw what is meaning of unstable programmer

don't do that if you have anything connected in those pins...

read the datasheet, page 14 says everything you need about the Vss pins, they are the ground reference for logic and i/o pins, as in digital ground, it means that all logic and i/o pins need all the Vss pins conected to ground so they can output "ground" or Low levels... one advice, if you have some Vss pins conected and the uC ON, it will not do much good hot disconecting the Vss... all internal logical gates need the Vss tied to the ground, so untieing the Vss pin 5 will cause an malfunction ! If you do this kinds of things it is possible that you may have allready burnt some internal gate or something like that...

If the uC internal gate design only needed 1 pin for Vss they would have done that to simplify costumers designs, they might be there because they can't connect them inside too...

Remember that PICs may be cheaper than the other uCs but they still cost money LOL

One thing i've learned all this years is to read the manual or datasheet first (Try to give a look in all config words and pin specs first, then go reading slowlly) !



Get another = PIC and try the same program,
oh, i allmost forgot, your config work seems ok.

Also to start, the best thing to do is getting an Pickit 2 Debug Express kit, it comes with examples, PIC and programmer debugger, this is the best option to start. Cheap and easy !

Have fun !

No problem

Check this post here :
Inchworm ICD2 review

the inchwork is somewhat like Lothar's ICD2 Clone, or try posting another Thread with this subject : "Lothar's ICD2 Clone - Who uses it ?"


Have fun.

Situations like this is I completely satisfy with my "code" & hardware I'll more concentrate on the config word.I'll try to change the OSC type ex:change to XT, or EXT RC & see how it goes.

Because I have met many PICs that they don't support some type of OSC.

Recently I found that INT RC is working but XT mode is not working.
Another PIC XT is working & INT RC is not working.

Its also an PIC 16F628A.

Lothars ICD2 is a classic design, it's been copied (yes even by me) countless times. Not even sure if it's the original.
Now I'd build a PICkit2 over an ICD2, you can simplify the PICkit2 design (see my Junebug schematic) with even less parts than the Inchworm and it's a better programmer to boot. USB support, fast, simple, reliable, lots of extras like the Logic Analyzer & USB tool.

many thanx for your replies
as Mr. gayan said i try with different osc types XT, ceramic resonators ,RC intenal osc
but non of them succeed