PIC18F4520 support in latest CCS and "stable" CCS?

rwyoung · Joined: 12 Nov 2003 Posts: 563 Location: Lawrence, KS USA

I am looking to use the PIC18F4520 in an upcoming project. My support contract for CCS has expired so I will be purchasing a new subscription and upgrading to PCHW to add PIC18 support.

Key features of the F4520 (40MHz and 5.0V) I'm looking at are:

1) faster ADC (only using single input so no scanning, planning on driving input with op-amp due to level shift and gain requirements, also planning on supplying 4.096V as reference to Vref+ pin)- any issues in CCS generated code?

2) ICSP and debug - any known issues with ICDS-20 and PIC18s? I can upgrade to the ICDU-40 as part of project costs.

3) Large RAM & ROM size. Expecting to use most of RAM (75 to 80%) as sample storage buffer prior to download via USB (FT245 chip) - any known issues?

Not very concerned with power consumption or unit cost as this will be a small production run. Overspending a bit on the microcontroller is a non-issue to get the project finished in short order.

All of my previous PIC experience has been with the PIC16 family. I've used nearly all the entries in the 16F tree and with very good results.

I have no problem with work-arounds where I need to write my own code to support a perpherial or feature. Quite comfortable with C and PIC assembly language. Also very comfortable with mixed signal circuit design and low-noise microcontroller vs. analog issues.

Thanks for your time in reading this and making suggestions reguarding CCS code issues and work-arounds. Cool

_________________
Rob Young
The Screw-Up Fairy may just visit you but he has crashed on my couch for the last month!

future · Joined: 14 May 2004 Posts: 330

After a brief look at the errata sheet, I wouldnt build anything with these chips.

rwyoung · Joined: 12 Nov 2003 Posts: 563 Location: Lawrence, KS USA

ckielstra · Joined: 18 Mar 2004 Posts: 3680 Location: The Netherlands

The errata sheet was updated with 4 new issues just over a month ago, this really would make me feel nervous about this device. Also consider this is the first stepping of this device.
I do have slightly better feelings about the PIC18F4525 which is in it's A3 stepping right now and has only 10 versus 20 known errata's.

If you don't need any of the newer features like autobaud and larger selection of power down modes, then I would recommend to use the old and well known 18F452.