How much C source code can I fit in 4K or 8K-words?

[mk3]

MCU choice

I've used in the past Motorola HCx11, HCx05, and Rabbit R2000 to control
some product projects of mine.

Now for a number of reasons I need to use some other MCU, and I was looking at PICs. I'm oriented towards 16F87x group, and I can get CCS PCWH C compiler. My question is: in 4 or 8K-words how much C source code can I fit? :?: I haven't the necessary MCU experience to make my mind. The project is a medium complexyty one, with not too much control code, but more in the user interface section... I won't begin writing my app. and then discover that it can't be made to fit the MCU mem size

Every suggestion is very welcome :wink: , also of using other MCUs (18F?)

 

[C-Man]

Re: MCU choice

I have an application for a PIC 16F877 of about 5000 lines c-code which fills this processor to the limit.

The same application fills a PIC 18F452 to abou 52%

I am using Hi-Tech Compilers for both as this one is able to pack about 10 to 20 percent more code into a pic as the CCS but on the other side it is no as easy to handle as the CCS.

You should also look at Atmels AVR series very nice processors with a lot of peripherals, speed and codespace from 8 to 128k.

Maybe you could also use 8051 derivates the 89C51RD2 for example has 64K codespace.

best regards

 

[ME]

I think you should have a look at The Atmel AVR family, it is very similar to the PIC, but have a more modern arcitecture. It is more optimised for C code, than the PIC and much faster, the generated code from an AVR compiler is smaller than the code from a PIC compiler.
Atmel makes a very good and cheap programmer/develompment board for the AVR, it is called STK500.
If you want to use assembler, I think the AVR is easier to use than the PIC too.

You could also consider the Texas MSP430 family and the PIC18F family.

All the above mentioned MCUs are with flash program memory.

Pic or Avr ?: **broken link removed**

PIC or AVR how to decide: **broken link removed**

 

[mk3]

Re: MCU choice

Thank you for answers and trhead links. I must check PIC vs. AVR quantity prices too... :? and I'm already looking to the TI prods. for other work in the future.

 

[eltonjohn]

Re: MCU choice

Hi Just one word ..
I have worked with PICS, AVR and lately wit TI's MSP430F . And i find that these last ones being 16 bits CPU are not as efficient in CODING as AVR or pics ..

Just a word i said!

 

[ME]

Another thing to consider is that you can get good quality C compilers at a lower price for AVR than for PIC because of the simpler MCU arcitecture.
You can even get the free GCC compiler for AVR.
Personally I use the Codevision AVR compiler, which is very nice and easy to use. It has built in codewizard, similar to the CCS PCWH compiler codewizard for PIC.

 

[talenat]

Re: MCU choice

Hi,
AVR are MCU to go with.
You are newbie and www.avrfreak.net is a must for you.
I don't think PIC have anything like that ( I mean support ).
I have switched from PIC to AVR and never looked back.