Saving space - close to 128k

Hi guys,
i need to find more code space as a result this requires some " clean up " of existing working code

i have recovered 10k in space so far , by changing any thing with an " and " to 2 x 1f statements instead. but this is not the only answer ( this saves about 60 bytes per " and" statement - yes i have a lot of compares for data matching

is there some other common way to change code to save compile space ?

looking at Lookups and anything with a string seems to be the next targets

any further advise

regards


Dheldon

Without seeing or knowing anything about the code it's not easy to say but here are two general things to try:

* Obviously, pretty much anything that you're doing more than once thru out the code AND is more than two or three instructions should be made into a subroutine and called with a GOSUB. Ie, it's not worth putting something like PortB.0 = 1 as the single instruction in a subroutine but as soon as there's a couple of instructions it gets worth it. Easy enough to try and see the effect.

* Use multiple IF's instead of SELECT CASE.

Post a specific section of code, wait and see what comes back.

/Henrik.

hi hendrick,

there are some 25 major sections with over 60,000 lines of code in the main program structure and the 3 support code programs for sub structures that load the flash , with graphic fonts , symbols , menus , search tables , option dephalts tables , banners , strings for serial and xls file constructs codes , serial code tables etc before the main program can be run flash is full with about 1mb of data , so posting a specific section would not seem like it would help a lot just yet

so general approach to clean seems the best starting point.,

the code for the main is now at 115k , it was at 126k before the first sweep of clean which took me 12 hours to get to , i am hoping to still find about 15k , to allow the other sections to be be written and still fit into the 128k

the code has been growing slowly over the last 3 months , but i am faced with a clean that has to yield real space , now i want to get the next sections done . such secure bootloader , and search routines etc ,

i would love a larger chip but that just not an option using pbp after 128k and puting more chips on which may have to be a real option , is not one i want to do, if i can avoid ;(

options
1. longs - droping and modifying code that use longs so longs are not needed - save about 3k up front
2. search option for data , - i think i need to look how i maybe best to do this as " multi "and" and match statements are killing me on space
3. be a better programmer - still working on that one

Hello,

Have you consider a serial eeprom? A 256k could hold your font tables and images etc, freeing up a lot space
on your main processor.

yes , i have already put 64mb a flash chip , for fonts , etc

what i think i need to do is look at how to search / format of the record table better handled in pbp ,

currently the methode is

if value 1 AND value 2 and value 3 then
if value 4 or value 5 = 1 then

get those records

each value may have upto 20 indexed varables attached to it so so although searching can take a few moments the amount of " and" statements to do search parameters needs to be addressed


i removed all long varables for the 2 main routines that use them , and changed the code to use 2 word values , which gave me back a massive 5k

i like pbp , but now i am is hitting the wall cos of lack of support for larger chips



each record has a
bout the tables are 50bytes per record stored in flash as data is accumulated , some recor

There are a few threads that talk about this. I started one thread a few years ago asking on how to optimize the program and save programing space.

Try to use a lot of LOOKUPs. Avoid using WORD variables whenever is possible. If the same code is repeated a few times, then create subroutines and use GOSUB.

Saving your fonts and data in an external EEPROM memory is not a bad idea.

yes i would recommend an external flash / eeprom for most projects , flash is so cheep ( 64mbit = $0.14c usd / per 100 ) and when designing boards , the extra design allows for alot of options for future expansion where a change of chip may be avoided due to code space issues.

putting EVERY serial string external to the PIC has saved me a lot of valuable program space , i have started to construct a library of common words , and phrases need for the project and is loaded into the flash