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B15HOP
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Joined: 11/09/2015
Location: Australia
Posts: 15

Posted: 09:02pm 16 Sep 2015

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I'm back again. Now with a 2nd problem.

My little Pic32 micromite is doing well. I seem to be having more trouble programming in MMBasic than I would in C.

The issue is that I need to take input pins using SetPin xx, din, pulldown and write a function that takes say 5 pins and turns it into a number. ie

SetPin 15, din, pulldown
SetPin 16, din, pulldown
SetPin 17, din, pulldown
SetPin 18, din, pulldown

SetPin 21, din, pulldown
SetPin 22, din, pulldown
SetPin 23, din, pulldown
SetPin 24, din, pulldown

The pins all collect either a 1 for on or 0 for off. How would I make it so that it makes a number with the binary inputs. Say I have switch 24, 23, and 22 on... and 18 on. So effectively that would be 00010111 ie binary for 23 in decimal. Then set it as a variable. I'm not sure how to convert strings or pins into a number.

Do I just do it manually. Ie pin 24 adds 1, pin 23 adds 2, pin 22 adds 4, pin 21 adds 8 etc...? Or is there a more simple way?

Cheers.

matherp
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Joined: 11/12/2012
Location: United Kingdom
Posts: 10406

Posted: 09:05pm 16 Sep 2015

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Do I just do it manually. Ie pin 24 adds 1, pin 23 adds 2, pin 22 adds 4, pin 21 adds 8 etc...? Or is there a more simple way?

The PORT function will do exactly what you want

B15HOP
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Joined: 11/09/2015
Location: Australia
Posts: 15

Posted: 09:15pm 16 Sep 2015

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I'm using the port function already funny enough. But it's for writing dout to a 7seg.

Does it read pins in as well? I'm just reading pins from two banks of 4x switches.

WhiteWizzard
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Joined: 05/04/2013
Location: United Kingdom
Posts: 2948

Posted: 09:22pm 16 Sep 2015

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Many ways to do it. Using PORT is good if pins are in 'blocks' of sequential pins. If not then another way is (using your pin numbers):

xx=pin(15)*128
xx=xx+pin(16)*64
xx=xx+pin(17)*32
xx=xx+pin(18)*16
xx=xx+pin(21)*8
xx=xx+pin(22)*4
xx=xx+pin(23)*2
xx=xx+pin(24)

WW

matherp
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Location: United Kingdom
Posts: 10406

Posted: 09:23pm 16 Sep 2015

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Quote Does it read pins in as well? I'm just reading pins from two banks of 4x switches.

These is a PORT command (output) and a PORT function (input). Look in the function section of the manual for details of the input version

B15HOP
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Joined: 11/09/2015
Location: Australia
Posts: 15

Posted: 09:32pm 16 Sep 2015

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I did read that part in the manual but didn't quite understand it.

[code]
DIM INTEGER Init_Number = port(24,-4,18,-4)
[/code]

Bunching commands together doesn't always seem to work. Or doesn't it take negitive numbers?

WhiteWizzard said Many ways to do it. Using PORT is good if pins are in 'blocks' of sequential pins. If not then another way is (using your pin numbers):

xx=pin(15)*128
xx=xx+pin(16)*64
xx=xx+pin(17)*32
xx=xx+pin(18)*16
xx=xx+pin(21)*8
xx=xx+pin(22)*4
xx=xx+pin(23)*2
xx=xx+pin(24)

WW

That will work, but I thought maybe there was a way to do it on one line of code. :)Edited by B15HOP 2015-09-18

Grogster

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Joined: 31/12/2012
Location: New Zealand
Posts: 9643

Posted: 09:42pm 16 Sep 2015

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I just use N=PORT(1,4) or N=PORT(1,4,61,4)(for the 64-pin MM+)

The first example will read pin1,pin2,pin3 and pin4, and save the binary value of the combined pins in variable N, and the 2nd version will read an 8-bit binary number on pins 1-4 and pins 61-64 on the MM+, and save the value in N.

You make reference to -4, which is illegal I think?

EDIT:

SetPin 15, din, pulldown
SetPin 16, din, pulldown
SetPin 17, din, pulldown
SetPin 18, din, pulldown

SetPin 21, din, pulldown
SetPin 22, din, pulldown
SetPin 23, din, pulldown
SetPin 24, din, pulldown

...in your case would become:

N=PORT(15,4,21,4)

Variable 'N' will contain the value of all 8-bits of your two switch banks.

Edited by Grogster 2015-09-18

Smoke makes things work. When the smoke gets out, it stops!

matherp
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Joined: 11/12/2012
Location: United Kingdom
Posts: 10406

Posted: 09:45pm 16 Sep 2015

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Quote DIM INTEGER Init_Number = port(24,-4,18,-4)

Try:
DIM INTEGER Init_Number = port(21,4,15,4)

B15HOP
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Joined: 11/09/2015
Location: Australia
Posts: 15

Posted: 09:50pm 16 Sep 2015

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Grogster said I just use N=PORT(1,4) or N=PORT(1,4,61,4)(for the 64-pin MM+)

The first example will read pin1,pin2,pin3 and pin4, and save the binary value of the combined pins in variable N, and the 2nd version will read an 8-bit binary number on pins 1-4 and pins 61-64 on the MM+, and save the value in N.

You make reference to -4, which is illegal I think?

EDIT:

SetPin 15, din, pulldown
SetPin 16, din, pulldown
SetPin 17, din, pulldown
SetPin 18, din, pulldown

SetPin 21, din, pulldown
SetPin 22, din, pulldown
SetPin 23, din, pulldown
SetPin 24, din, pulldown

...in your case would become:

N=PORT(15,4,21,4)

Variable 'N' will contain the value of all 8-bits of your two switch banks.

matherp said

Quote DIM INTEGER Init_Number = port(24,-4,18,-4)

Try:
DIM INTEGER Init_Number = port(21,4,15,4)

Yeah I just thought it could read the ports backwards but I guess not. Guess it doesn't matter if I flip the breadboard around to read them upside down. :)

Grogster

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Location: New Zealand
Posts: 9643

Posted: 09:53pm 16 Sep 2015

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Ahhhhh - I see what you mean by the -4 now. No, pins must be numbered consecutively to use the PORT function. I will watch this thread, and see if anyone comes up with a brilliant solution - someone usually does.

Smoke makes things work. When the smoke gets out, it stops!

B15HOP
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Joined: 11/09/2015
Location: Australia
Posts: 15

Posted: 10:03pm 16 Sep 2015

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Grogster said Ahhhhh - I see what you mean by the -4 now. No, pins must be numbered consecutively to use the PORT function. I will watch this thread, and see if anyone comes up with a brilliant solution - someone usually does.

Both techniques definitely work. The function just can't take negitive values so Mr Wizzard's option is the solution for now. But I really do like having just one line of code. :)

matherp
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Location: United Kingdom
Posts: 10406

Posted: 10:22pm 16 Sep 2015

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You can go:

DIM INTEGER Init_Number = port(24,1,23,1,22,1,18,1,17,1,16,1,15,1)

or any other order to get what you want

WhiteWizzard
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Joined: 05/04/2013
Location: United Kingdom
Posts: 2948

Posted: 10:25pm 16 Sep 2015

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B15HOP said . . so Mr Wizzard's option is the solution for now. But I really do like having just one line of code. :)

xx=pin(15)*128 +pin(16)*64+pin(17)*32+pin(18)*16+pin(21)*8+pin(22)*4+pin(23)*2+pin(24)

B15HOP
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Joined: 11/09/2015
Location: Australia
Posts: 15

Posted: 06:23am 03 Oct 2015

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Cheers for your help guys. Appreciate it a lot. :)

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