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Lilmanmgf
- 13th January 2005, 02:06
I got a brand new 16F84A from jameco. I have an epic programmer and I am using picbasic pro. When I go to programmer the chip it says error not blank so I erase it but get the same error. It says the problem is in 0000-0001. When I look at the code on the chip in that section instead of having 0000 like all the others it has 3fff. Is there anything I can do to fix this or do I need to buy a new chip?

BobK
- 13th January 2005, 03:08
This may sound like a dumb question but do you have the programmer plugged into a power supply? What you describe is what I have encountered when I forgot the PS. Also have you checked all of your settings witin the program for the proper programmer?

BobK

Lilmanmgf
- 13th January 2005, 03:25
Yeah its the right power supply.

mister_e
- 13th January 2005, 14:14
how do program your PIC : directly in the EPIC socket or in-circuit?

NavMicroSystems
- 13th January 2005, 23:01
Sorry,

I cant't help with that question, but I have another question related to the initial one:

Why is that "old" 16F84 still that popular?

I have never used it because there are many other 18pin PICs with more features available at much lower prices.

regards

Ralph

mister_e
- 13th January 2005, 23:42
Ralph

Why is that "old" 16F84 still that popular?

IMO it's so popular because it's one of the first one. If you do a search on the web, you'll find more project with this PIC16F84. In the begining he made his popularity here in some *black box TV project* ;0)

AND, most free programmer (PONYPROG,ICPROG,EL CHEAPO... ) has been developed around this one. I still have those in stock. when i want to decrease my stock(about 300 remain as now), i use them in some simple tasks (still pain in the neck when you MUST use external oscillator... ) Like those 16C54 that i still have(about 200)... i must found something to use them :0)

BUT i heard that in some Country, this PIC16F84 is the less expensive one. Here in Montreal, if you want to experiment with PIC, local/public distributor (active, addisson, master-vox...) will hold only 16F84,16F877,12C508 and SOMETIMES at some place 16F628. This is why i do order from Digikey, Newark or else other.


Lilmanmgf

Seems like a bad PIC... i'm really not sure but. I still asking the same question. Do you program your PIC in-circuit or directly in the EPIC socket. CAse in-circuit, try to erase directly in the EPIC socket. Can you monitor the MCLR pin when you program it? Should be around 13Volts.

NavMicroSystems
- 14th January 2005, 00:36
Originally posted by mister_e

... Like those 16C54 that i still have(about 200)... i must found something to use them


If thay are DIP, you could use them as Pins on your PinBoard ;-)

regards Ralph

mister_e
- 14th January 2005, 00:41
LOL... yep they're close to that. The only *close intelligent* use i found for them is backpack lcd stuff or 7 Segment multiplexing display... still good enough for that... I really hate those OTP since they don't have all a FLASH version... still stoneage UV method.

Lilmanmgf
- 17th January 2005, 17:36
sry for taking so long. Its in the epic socket. I been using one at school for a while and I finally got one for myself. It never game me an error like this before. I guess I'll buy a new chip. Its annoying because I finally bought a programmer and I just test a simple program and...nothing.

mister_e
- 17th January 2005, 18:30
mmm, be sure of the voltage of the power supply first. Be sure you have the right one. Test MCLR when programming too. It's maybe only caused by a *close to be dead* power supply.

Lilmanmgf
- 17th January 2005, 21:22
I just bought it from JameCo so its brand new. I tested it with the epic programmer at school and it worked so I'm guessing its the chip.

Lilmanmgf
- 15th February 2005, 22:37
Okay I have no voltage over the mclr pin.

mister_e
- 15th February 2005, 23:18
:)

Lilmanmgf
- 16th February 2005, 01:43
i tried with fresh batteries as well and still no go. Time to get a new chip.

mister_e
- 16th February 2005, 04:24
You have no voltage on MCLR pin. What about the VDD?

If you don't have any voltage on MCLR pin but on VDD... PIC will never start. MCLR must be tie to vcc via resistor with PIC16F84