My comments below on various replies.. > You COULD switch to assembler, of course... COULD but WONT! :-) > Add another 16F88 - or something smaller just to look after (eg) the > LCD dispay etc.? Already doing that as the LCD display and keypad is remote and it has it's own PIC16F88, with comms over an RS232 like interface. I send instructions like "put this string of characters on line 2". > If you can tweak the board how about adding an external serial memory > chip? The menus probably won't be accessed often so loading them over a > serial link may not be bad? Not keen on that (hardware wise), but could use on chip EEPROM to store some strings I guess, but really that would only be a saving of a few hundred bytes max. > you could try the 18F1320, no more instruction words but its 18 series > which should be able to do the same C code in less words (and since your > coding in C migration to the pic18 core shouldn't be too hard). Interesting idea... so I did a quick test to try it. Compiling for PIC16F88 --> 3669 words (89.6% of 4096 words). Compiling for PIC18F1320 --> 3511 words (85.7% of 4096 words). Used Hi-Tech PICC and PICC-18 Compilers. Commented out about a dowzen lines that wouldn;t compile without some tweaking. Not a huge difference in code size although it does at least tend to confirm that 18F programs can be more size efficient as one might expect. Other bit's and pieces... I'm not using floats, printf or any large data structures. My menu structure is not great but not obese either. The one thing that pushed me over the top was adding CRC checking for my 1 wire temperature sensors - needed it because I'm getting the occasional erroneous result. This adds about 300 program words. Having made some improvements and nips/tucks in other areas I think I will keep plodding along and get as much code as possible squeeezed in to my prototype(s) - gotta be working by the end of this week! After that I'll have to look at a bigger micro, new PCB, seems like there are a few possibilities. It's a shame I can't find anything about a PIC16F89. A couple of ICE vendors make pods described as being for PIC16F87/88/89 so perhaps this is something scheduled for the future, and just maybe the difference is it has larger Flash? Can't help the feeling that I've read about it somewhere. Thanks all for the tips. -- Brent Brown, Electronic Design Solutions 16 English Street, St Andrews, Hamilton 3200, New Zealand Ph: +64 7 849 0069 Fax: +64 7 849 0071 Cell: 027 433 4069 eMail: brent.brown@clear.net.nz -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist