MIcrochip: Date Code to Silicon Revision - Page 1
Forum section: electronics / general

author: jpanhalt
author_rank: Super Contributor
timestamp: April 23, 2022, 10:54:13 am
content: I bought some Microchip PIC16F1xxx MCU's and know how to find the silicon revision code once the chip is connected to a programmer, but these are TQFP44 chips and ZIF-like adapters are expensive.I assume Microchip can correlate the date code for a chip with silicon revision, but I cannot find that data. Does anyone know where to get it?The option of buying directly from Microchip and specifying the revision number was not practical.EDIT: The date code in question is 2119CR8, which I read as: year 2021, week 19. The latest errata revision is October, 2014. Is it safe to assume the silicon revision is the latest version?

author: woofy
author_rank: Frequent Contributor
timestamp: April 23, 2022, 12:43:08 pm
content: I would not normally trust a date code to rev correlation, but 2014 to 2021 is a big leap. Its likely the errata of concern has been fixed.If they are from a trusted source and you are happy the devices are from the same batch, it would be reasonable to assume they are all the same rev.Try building one and read the rev code.

author: jpanhalt
author_rank: Super Contributor
timestamp: April 23, 2022, 01:37:33 pm
content: Thanks. I wish Microchip would be so responsive.Here's more detail. The code was developed with a 16F1783 on a soldered breadboard. The first prototype board was designed for a 16F1789 in a TQFP44 package for space reasons and additional inputs (switches). That chip has been a nightmare, and others have had the same experience using ICD3/MPLAB 8.92. Last episode caused "locking" MPLAB in an error mode, err 0086, which isn't even shown in the ICD3's user manual.* Both MPLAB and ICD3 functioned normally with the 16F1783 chip. An earlier version (8.89) running on an XP PC was then tried and worked with both the 16F1783 and 16F1789 board. I removed and reinstalled 8.92 on my main PC, but used the earlier .jam file from version 8.89. (A problem with the latest .jam file was mentioned in the other user's experience.) So far, that is working again. A problem report was made to Microchip on Monday. There has been no substantive response.Searching Mouser and Digikey for available chips, I found the 16F1784 and 16F1717, which were ordered and arrived late yesterday. The 16F1717 has a bunch of peripherals that I don't need. The 16F1784 has the attached silicon errata. EDIT: The latest version is not affected. I use bra and brw instructions freely and have two interrupts active plus WDT.Changing that chip will be a PITA, so I want to do it only once and would prefer the simplicity of the 16F1784, if that issue has been resolved. Are you willing to bet your life on what seems like a rational assumption?If a few others come to the same conclusion, then I will follow it too.Regards, John*The first happened in March with basically the same symptoms but was easily fixed by changing the chip to a 10F202 in configure, reloading the ICD3, then changing back to the 16F1789 and reloading.

author: fchk
author_rank: Frequent Contributor
timestamp: April 23, 2022, 03:13:51 pm
content: MPLAB is quite old and has been out of support for a long time. You are supposed to use MPLABX now.fchk

author: NorthGuy
author_rank: Super Contributor
timestamp: April 23, 2022, 04:32:55 pm
content: Microchipdirect has some stock of PIC16F1784 in MV package, so you can buy them. You can inquiry, or even request the specific silicon revision. Anyway, the chances of this BRA bug being still there are slim to none.

author: jpanhalt
author_rank: Super Contributor
timestamp: April 23, 2022, 04:50:39 pm
content: Thanks, NorthGuy.If I get moved to change the chip (i.e., one more freeze up), I think I will go with the 16F1784.Yes, I know you can specify silicon revision at Microchip. I wanted something that shipped fast and without having to pay the large FedEx charges.@fchk"MPLAB is quite old..." I am almost 80. Birds of a feather flock together.I considered switching twice in the past. First time was right after MPLabX came out. Second was a few years later. Both times were a disaster Once burned, twice shy. Twice burned, shame on me.I can only code in Assembly and have heard that current MPLabX isn't that bad. I guess you have to go to relocatable code, but that is not such a big deal if you start the project that way. Maybe I will give it a try, but definitely not at the end of a project I have been working on during the past 2 or 3 Winters.

author: Tomorokoshi
author_rank: Super Contributor
timestamp: April 24, 2022, 04:11:22 pm
content: I moved a project from MPLAB 8 to MPLAB X. It used the CCS compiler. I always ran the compiler from the command line. It was impossible to make it work from MPLAB X because when CCS was queried, it would display a window with version numbers. This would happen all the time. It was difficult to turn off because MPLAB X would "helpfully" search for compilers every time it was started, which would cause CCS to display the version window. Eventually I was able to make MPLAB X to stop searching for compilers. So I still compile from the command line, and MPLAB X is only used for editing.I used the project import tool. It's marginally useful, so I deleted the project and tried again a couple time before the project structure worked properly.