Building statements?

[curt2go]

I am looking at hooking up to a computer(That part is done) and build statements inside the code that are executed.These will be executed after compile time. Like building some if statements or more insticate. I am not really sure where to start. I have not used pointers much and not sure if it can be built from a string with a pointer. Let me know if you guys have any ideas. I have done a search but not much yet.. Thanx in advance.. TTY

[curt2go]

Here is an example if it helps..

Statement1 :

taken from user: if input 1 is high then make output 4 low.

if(input(pin_a2))
output_low(pin_d4);

Statement 2:

Taken form user : if input2 is low or input 4 is greater than 3 then output 7 high and 4 low.


if((input(pin_a1) || (a2d_value > 3))
{
output_high(pin_c6);
output_low(pin_c3);
}

Keep in mind these are all fictional I just threw in some pin number.. Thanx.. TTY

[curt2go]

Bump....
Is this just really hard or is it so simple that I am missing so no one will respond? Let me know.. TTY

Just looking for some ideas.. Thanx

[Ttelmah]

I don't think anyone has the faintest idea of what you are actually asking....

Best Wishes

[curt2go]

I will try to articulate.

I have 8 inputs and 8 outputs. I am taking information from the PC to let the pic know what to do.

I am looking for input from the user to build if statements from the input from the user.

So lets say the user inputs that he wants the output 9 to go high when inputs 4 and 5 are set high. I need to build that statement inside my code.

So the pic is running and it get an input for a new instruction.(Above) so now it must impliment the above statement in the code. So it must be able to execute the user defined staement somehow. I know I could do it with 1000 if and cases but I am looking to optomize it somewhat..

The user has the option or or's and's < > = and such..

I hope that spells it out a little better.. Basically building a staement from a string.. Thanx

[SET]

I think the poster is looking for a command interpreter? Where the command (string) can contain conditional execution statements. Create a syntax for your commands, then the code will follow from that..

[curt2go]

Exactly... Sort of a query builder type thing but the code is exectued while running.. Thanx

[curt2go]

Would it be easier to do this part in assembly rather than in C?

[SET]

Well.. I would do it in C..

The complication as I see it is what happens if you assign conflicting conditions, say

[curt2go]

Yeh it would be no problem if there was on a small number of possibilities but there is 8 inputs and 8 outputs and the use of < = > or and make the number of possibilities almost endless. That is where the problem is.

Thanx so far.. TTY

[Neutone]

You could look at it from the other direction. Each output could be assigned a conditional evaluation. When dealing with logic use logic operators. "< = >" are not logic operators.

Output1 = Input1 || (!Input2 && Input3);

This is inherently consistent. I think it's easier to read than an if statement. The only problem is how to encode, store, decode and evaluate the conditional statements.

[curt2go]

Sure that is fne but still stuck on how to build the statement.. TTY

[SET]

[curt2go]

I still agree but that is the easy part. How do you build that equasion or statement whille the pic is running? Without using 10,000 if's.

TTY

[ckielstra]

As was mentioned before what you want to build is called an interpreter. This is not related to the CCS compiler or PIC processor and from the minimal response you receive here it looks like the expertise you are looking for is not available in this forum.
My suggestion is to use Google and look for a better place to post your question.