A little help needed with arrays in PicBasicPro please

B

bigal_scorpio

Active Member

• Apr 5, 2011

• #1

Hi to all,

I am still learning Pic Basic Pro and have come up with a problem in understanding Arrays!

From the manual I understand how to define the Arrays name and size eg. sharks VAR BYTE [10] gives an Array with 10 elements and I think I understand how to access the elements. BUT what I am baffled about is the method of loading the data I want into the array?

I mean to say, continuing the manuals shark theme, if I wanted the array to consist of tiger, great white, lemon, nurse etc, what is the actual syntax I would use to make the array and where would this line/s be placed? IE inside the main, before main or after main?

Any example would be most welcome.

Thanks for looking...........Al

 

Ian Rogers

User Extraordinaire

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Most Helpful Member

• Apr 5, 2011

• #2

I'm not sure that PBP allows multidimensional arrays! An array of strings has usually two dimensions ie. names[10][string length] . To do this you will need to make n' arrays of fixed length ( longest text ) and initialize them individually (laborious) The easiest way for you to do this is with the lookup command

Code:

        For B = 0 to 5			        ' Count from 0 to 5
		LOOKUP B,[“Hello!”],B1	' Get character number B from string to variable B1
		array[B] = B1	                ' Send character in B1 to array
	Next B				        ' Do next character

This is the example from the manual

Cheers Ian

 

Last edited: Apr 5, 2011

B

bigal_scorpio

Active Member

• Apr 6, 2011

• #3

Hi Ian,

Still baffled mate. The following code compiles and burns with no errors but does nothing at all.

I have leds connected to PortB and ground and expected them to light as the program stepped through the lookup.

I am obviously not getting something about the lookup!

Any help please.......Al

Code:

 MAIN:
 
 FOR N = 0 TO 7
 
 LOOKUP N ,[1,2,4,8,16,32,64,128], RESULT
 
 NEXT N
 
 PAUSE 1000
 
 PORTB = RESULT
 
 GOTO MAIN
 
 END

 

ericgibbs

Well-Known Member

Most Helpful Member

• Apr 6, 2011

• #4

hi Al,
The PORTB=RESULT should be in the FOR NEXT LOOP....

 

Ian Rogers

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• Apr 6, 2011

• #5

And the Pause 1000! or you won't see anything.

Cheers Ian

 

B

bigal_scorpio

Active Member

• Apr 6, 2011

• #6

Hi Eric,

Changed the code as you pointed out but still no joy at all. Doh!

Al

 

Ian Rogers

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• Apr 6, 2011

• #7

Have you set PORTB as an output? What size limiting resistors are in place.

Cheers Ian

 

ericgibbs

Well-Known Member

Most Helpful Member

• Apr 6, 2011

• #8

bigal_scorpio said:

Hi Eric,

Changed the code as you pointed out but still no joy at all. Doh!

Al

Click to expand...

Did you do Ian's PAUSE change, most important.

 

B

bigal_scorpio

Active Member

• Apr 6, 2011

• #9

Hi Eric and Ian,

Yes I did Ians too but didn't see his post until after I had posted your reply.

Here is the new code but still not working as expected, not a flicker!

PS fuses set to MCLR off, WDT off, PWR on BOD off

Al

Code:

 MAIN:
 
 FOR N = 0 TO 7
 
 LOOKUP N ,[1,2,4,8,16,32,64,128], RESULT
 
 PAUSE 1000
 
 PORTB = RESULT
 
 NEXT N
 
 GOTO MAIN
 
 END

 

Ian Rogers

User Extraordinaire

Forum Supporter

Most Helpful Member

• Apr 6, 2011

• #10

I hate to ask this (watching fingers) are the LED's the right way round?

Cheers Ian

 

ericgibbs

Well-Known Member

Most Helpful Member

• Apr 6, 2011

• #11

hi Al,
This runs in Oshonsoft, had to make a few changes.

Code:

AllDigital

Dim n As Byte
Dim result As Byte

TRISB = 0

main:

For n = 0 To 7

result = LookUp(1, 2, 4, 8, 16, 32, 64, 128), n

'PAUSE 1000

PORTB = [B][COLOR=Red]RESULT[/COLOR][/B]

Next n

Goto main

End

Woops, corrected an error in my listing...

 

Last edited: Apr 6, 2011

Mike_2545

Super Moderator

• Apr 6, 2011

• #12

What are you attempting to do on PORTB? This

PORTB = RESULT

Click to expand...

really makes no sense to me...

 

ericgibbs

Well-Known Member

Most Helpful Member

• Apr 6, 2011

• #13

Mike2545 said:

What are you attempting to do on PORTB? This really makes no sense to me...

Click to expand...

hi Mke,
It will light LEDs PORTB.0 thru PORTB.7 on/off sequentially

 

Mike_2545

Super Moderator

• Apr 6, 2011

• #14

Hi Eric....Thanks I will have to try that out, just never addressed an entire port like that.

 

Ian Rogers

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• Apr 6, 2011

• #15

Just as an after thought What processor are you using?

Ian

 

ericgibbs

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Most Helpful Member

• Apr 6, 2011

• #16

Ian Rogers said:

Just as an after thought What processor are you using?

Ian

Click to expand...

For Ref, I used a 16F628A.

 

Ian Rogers

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• Apr 6, 2011

• #17

I mean't the originator's processor, I don't know PBP but the larger processors use LATCB.

Ian

 

ericgibbs

Well-Known Member

Most Helpful Member

• Apr 6, 2011

• #18

Ian Rogers said:

I mean't the originator's processor, I don't know PBP but the larger processors use LATCB.

Ian

Click to expand...

I realised you meant Al's PIC, I posted the type I used as Ref, mainly for Al's guidance..

 

B

bigal_scorpio

Active Member

• Apr 6, 2011

• #19

Ian Rogers said:

I hate to ask this (watching fingers) are the LED's the right way round?

Cheers Ian

Click to expand...

Hi mate,

Yes, they are on my EasyPic5 dev board.

Al

 

B

bigal_scorpio

Active Member

• Apr 6, 2011

• #20

Hi Eric and Ian and Mike,

I am using a PIC16F873A, it was handy at the time.

And still no joy.

Al