Author Topic: otp (Read 9815 times)

siliconmix · « **on:** January 31, 2012, 10:46:29 am »

i'm new to mcu's.how do i visual identify a opt chip .?

wkb · « **Reply #1 on:** January 31, 2012, 11:56:40 am »

By reading the datasheets?

siliconmix · « **Reply #2 on:** January 31, 2012, 11:59:56 am »

but what does it say on the chip ?

wkb · « **Reply #3 on:** January 31, 2012, 12:01:56 pm »

Quote from: siliconmix on January 31, 2012, 11:59:56 am

but what does it say on the chip ?

A partnumber. That part# you cross-check with the datasheet and you know what kind of part you have.

siliconmix · « **Reply #4 on:** January 31, 2012, 12:07:10 pm »

pic 16f84a-04/p

ejeffrey · « **Reply #5 on:** January 31, 2012, 12:27:27 pm »

http://lmgtfy.com/?q=pic+16f84a-04%2Fp&l=1

That is a flash device not a OTP chip.

deephaven · « **Reply #6 on:** January 31, 2012, 12:28:55 pm »

Quote from: siliconmix on January 31, 2012, 12:07:10 pm

pic 16f84a-04/p

The answer is just a couple of mouse clicks away. Cut and paste 16f84a-04/p into the FindChips window here on this forum and you will see who stocks it. Click on that link, say Farnell and you will see a description which says it's a flash part, not OTP.

siliconmix · « **Reply #7 on:** January 31, 2012, 12:41:45 pm »

i didn't know that otp and flash are two different types ty for help.good now i'm getting somewhere.

wkb · « **Reply #8 on:** January 31, 2012, 01:43:14 pm »

Quote from: siliconmix on January 31, 2012, 12:41:45 pm

i didn't know that otp and flash are two different types ty for help.good now i'm getting somewhere.

Flash is electrically erasable. OTP is one time programming. So in case you have made a mistake using an OTP device it is
ready for recycling.

siliconmix · « **Reply #9 on:** January 31, 2012, 02:40:05 pm »

right i built this programmer.it works.i wiped whatever was on there.my only programming experience is with a zx spectrum years ago.so which will be the easiest way for me to start ?

alm · « **Reply #10 on:** January 31, 2012, 02:44:26 pm »

Getting a PICkit 3 and a PIC designed in this century?

siliconmix · « **Reply #11 on:** January 31, 2012, 03:07:00 pm »

it's free or not for me...meh

ivan747 · « **Reply #12 on:** February 01, 2012, 11:10:21 pm »

I have never got that design to work, and also the PIC16F84A is expensive and crappy. A modern $2 microcontroller (that's the price for 1 unit) from Microchip will perform better than that. Look at this: http://www.finitesite.com/d3jsys/16F628.html

siliconmix · « **Reply #13 on:** February 02, 2012, 08:26:42 am »

the programmer works with "picpgm developement " i didn't pay anything for the 16f84 as it was a pull.as i said i'm new to mcu's so i'm not going to spend a lot in case i don't enjoy it.

ivan747 · « **Reply #14 on:** February 02, 2012, 10:00:51 am »

You're not going to enjoy guessing what's wrong when the PIC doesn't run your code, but let's see, we don't know if it's going to work in the first try.

siliconmix · « **Reply #15 on:** February 02, 2012, 10:03:02 am »

it does work.the only thing you have to do is run the program in wdoze 98 mode.

ivan747 · « **Reply #16 on:** February 03, 2012, 02:52:06 am »

Great! The next step is to get a better programmer. If you're looking for a cheap hardware serial port programmer for 5V PICs you can get one of these: http://www.sparkfun.com/products/8
It's a JDM based programmer. JDM programmers are the most used kind of dumb programmers out there. You can get a similar one on eBay or look for a distributor in Wales.

The other option is to get the PICKit 3. It works flawlessly as a programmer and can be used standalone too (i.e. not tied to Microchip's MPLAB IDE), end of story. I haven't figured out how to use it as a debugger because I have never found a solution to a bug with the debugger function.

siliconmix · « **Reply #17 on:** February 03, 2012, 08:21:19 am »

thanks but i'm not buying anything i can make myself.

caroper · « **Reply #18 on:** February 03, 2012, 08:53:02 am »

Quote from: alm on January 31, 2012, 02:44:26 pm

Getting a PICkit 3 and a PIC designed in this century?

Quote from: siliconmix on February 03, 2012, 08:21:19 am

thanks but i'm not buying anything i can make myself.

How about a compromise then, build a PicKit2 Clone. I found this one that looks good for your needs.

http://www.mcuhobby.com/articles.php?article_id=7

I have not built it myself as I already own a PicKit2, PicKit3 and ICD3.
But I still prefer the PicKit2 when working with PIC16F chips, and it has some great software available for simple Logic and Serial Protocol analyses work.
So it is a good programmer, has some software debugging capability and some hardware debugging capability.
It wont work with the newer PIC32 chips, but it will work with far more than the one you have already built.

Cheers
Chris

siliconmix · « **Reply #19 on:** February 03, 2012, 08:56:28 am »

nice clone.small too.thanks

westfw · « **Reply #20 on:** February 04, 2012, 01:40:47 am »

For PICs, the OTP parts are the xxCxxx, and the reprogrammables are xxFxxx. Unless the "C" part has a glass window, in which case it's UV-eraseable.

Quote

the PIC16F84A is expensive and crappy.
A modern ... [like] 16F628

Yes. Except that the 16F628 is now also getting old. Microchip has a nice (?) habit of introducing new and better chips at lower prices, while keeping the old ones around at higher prices. The latest recommendation I saw for a beginner PIC was the 16F1827; it has the new "enhanced" core that gets rid of some of the more annoying points of the old PIC architectures.

Others advocate skipping the 16f series entirely and going to 18f or 24f...

Microchip is historically very nice about sending free samples. I'm not sure about Wales, though...


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Author Topic: otp (Read 9815 times)

alm

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