PSOC4 Programming Different Target

[dh-eaton]

I recently posted this question that was answered by Gautami_12, however, the answer was not clear and the site will not allow me to post a reply.  Gautami_12 shared the following images from the datasheet that shows  CY8C4248LTQ-L485 is an alternate part to CY8C4247LTQ-M475.  What I don't know is if the code has to be recompiled.  Currently the PSOC creator project is targeting CY8C4247LTQ-M475.  Will the object code compiled targeting CY8C4247LTQ-M475 work on CY8C4248LTQ-L485, or does the project need to be updated to target CY8C4248LTQ-L485 and the code recompiled?  Because the code is in production, recompiling the code presents configuration control challenges.  We likely do not want to purchase these alternate chips if the code will need to be compiled again to target the new chip.   

The originally posted question:

We have object code that is built targeting CY8C4247LTQ-M475 and everything works fine.  With shortages of chips we found availability of CY8C4248LTQ-L485.  Does anyone know if our object code will work on the CY8C4248LTQ-L485 without rebuilding it targeting the new chip?   From what I can tell the M series seems to be a scaled down version of the L series.

[BiBi_1928986 · Accepted solution]

Hello.

This question comes up all the time.  And, the answer is always the same.
No, you can not program the object code from one family of PSoC's into another family of PSoC's.  In fact, you can't even do that within the same family of PSoC's.

There are several reasons (details of which are found in the forum) why this does not work and is not reliable.  The highlights are:
1) FLASH programmer software checks device ID's against the object code and if they don't match, the programmer software won't program the device.
2) Different devices have different internal timing constraints which are optimized/flagged during the Build process.
3) Different temperature tolerances vs timing vs environment
4) Different memory sizes.  And this is further complicated when a Bootloader is involved.

It's not good news for you, but better to have a reliable product and keep the customers happy.