pic24 beginner

[mackrackit]

PicBasic compiles the basic code into assembly language.
If you are using an 18F chip MPASM then converts the assembly into HEX.
This is all done automatically when you compile your basic code. MPASM is free, it is part of MPLAB. When you purchase PBP a compatibe version of MPASM come with it.

Now you need a way to "squirt" the hex into the PIC. That is where the PicKit2 comes into play. There are other programmers out there. If you do not go with the PicKit2 MeLabs has some good ones. Beware of the clones though. Nothing but trouble. The last I flecked the PicKit2 war around $50 US.

So it boils down to needind PBP and a PicKit2 and a bread board or two and you should be good go.

[robertpeach]

ok thank you! you wouldnt believe how much thats helped!

also just wondering for what ive described to you, is it important to buy the picbasic pro, or is the picbasic sufficient enough for my needs? or are there other programs i could use that would do the same thing at a lesser price?

[mackrackit]

To be honest, PB Pro is all I have ever used from MeLabs.

Other programs... Folks around here seem to like PBP
a few years ago before I purchased PBP I tried the demos from some of the others. And here I am. I think most would agree that PBP is the most stable one out there and the support from MeLabs if needed is great.

Once you purchase PBP upgrades are only $25.

[Bruce]

I will 2nd what Dave says. PBP is the only way to go. 90% of everyone that's ever
purchased PBC from us over the years has returned within around 30 days to upgrade
to PBP. It's the best out there.

For your particular application, have a look at the 18F2431. The motion feedback module
has a capture option specifically for frequency measurements, and makes it incredibly
simple. It automatically captures the 16-bit timer5 value on every rising-edge.

It also has 10-bit A/D with up to 200K samples-per-second, with simultaneous 2-channel
sampling.

[robertpeach]

thanks for the feedback

to bruce, you say the 18f2431 is specifically for frequency measurements. would that mean I would no longer need to attempt to code my program to measure the 0 points and then measure the frequency from the timings between the zero points? also you say it does two simultaneously? i have 3 phases from my analogue signal, which are split into 3 different signals, all of which i need to measure the frequency of and get an average. is this still possible with this pic?

and would using the 18f2431 be alot easier than using a schmitt trigger and just measuring the frequency of 3 square waves using interupts? would there be 3 places on the pic i could make these inputs aswell?

thanks

[robertpeach]

ive decided after looking through the specifications in high detail, i think the 18f2431 is probably best suited for my needs, since i noticed it does have 3 digital inputs for my 3 signals that need their frequency measured, and it has the schmitt trigger integrated into its inputs.

im going to purchase the picbasic pro aswell, but im still dubious on the programmer... the pickit2, is a good site to purchase it from? and is the basic pickit2 good enough or is the pickit2 debug express something that is more suited for my needs?
(i notice the pickit2 startup kit doesnt have enough pin slots for the 18f2431)

thanks!

[robertpeach]

ok another reply by me...

basically i was wondering if i bought a picbasic pro, usb programmer with a zif adapter, and pic18f2431 would work?

additionally would purchasing a development board be something that would be needed? or anything of that such...

thanks sorry for so many replys ive been pretty active at this, and im trying to learn basic without a program to even write it in yet!

[Bruce]

you say the 18f2431 is specifically for frequency measurements

The PIC is not specifically for measuring frequencies. It just has a capture module
that makes it much easier to do since it will capture the value of Timer5 on every
rising edge - which is the period of the square wave.

also you say it does two simultaneously?

It can take 2 A/D readings simultaneously.

i have 3 phases from my analogue signal, which are split into 3 different signals, all of which i need to measure the frequency of and get an average. is this still possible with this pic?

Yes.

and would using the 18f2431 be alot easier than using a schmitt trigger and just measuring the frequency of 3 square waves using interupts? would there be 3 places on the pic i could make these inputs aswell?

Yes it has 3 capture inputs, and using built-in hardware to measure frequency is a good
deal easier than interrupts. All 3 capture inputs just happen to be Schmitt Triggers inputs
too.

If you do need to use interrupts, then I definitely recommend you take a look at Darrel
Taylors' Instant Interrupt routines. He's done some awesome work on these.

[Ioannis]

If you intent to use the programmer for serious work forget pickit and look for something solid and fast one.

I use for years the Pikprog2 that is discontinued and replaced by other newer models. The site is www.elnec.com and can program with ICSP or with a ZIF socket, PIC controllers, HCSxxx devices and EEPROMS too. New chips added every two months at no cost.

There are others of course in the net.

Ioannis