Quick question on PIC

[bigal_scorpio]

Hello to all,

Just built a circuit that uses the PIC16F628, and then realised that the one I have is a 628A.

Is the code from the older chip ok to use on the "A" version and do I need to use an "A" include file as opposed to the original one?

I am led to believe that the pins are exact on each version so I think the migration should work circuit wise at least?

Thanks.......Al

 

[dknguyen]

Use the A version of the include file. A means it's a silicon revision, but it's the same chip. So the software should still work (like you said the pinouts are the same). But the internal memory mapping might be different from the silicon revision, so use the A version of the include file.

 

[bigal_scorpio]

Includes

Use the A version of the include file. A means it's a silicon revision, but it's the same chip. So the software should still work (like you said the pinouts are the same). But the internal memory mapping might be different from the silicon revision, so use the A version of the include file.

Hi dknguyen,

Thanks for the swift reply, one more question though, since I am just beginning with PICs, where do these elusive Include files come from?

Thanks again........Al

 

[picbits]

I thought the A version had comparators while the older version didn't.

You might want to check how the ports are initialised if this is the case.

 

[kchriste]

where do these elusive Include files come from?

From MicroChip.
They are on your computer if you installed MPLAB in the default config:
C:\Program Files\Microchip\MPASM Suite
You can also read the migration DOC from Microchip do find out all the differences between the A and non-A versions:
https://www.electro-tech-online.com/custompdfs/2008/05/40048a.pdf

 

[bananasiong]

I thought the A version had comparators while the older version didn't.

You might want to check how the ports are initialised if this is the case.

I think the non A version has comparators too for 628.
87x family has no comparator for non A version.