Define byte as array of bits
George99
Posts: 16
I think I've had too much COBOL!
I want to create an array of bits, i.e. bits VAR Bit(8), change bits as needed, then use the result as a byte.
This works:
' {$STAMP BS2}
' {$PBASIC 2.5}
bits VAR Bit(8)
bits(6)=1
bits(0)=1
debug B0 ' displays A
...but I really don't like using that B0 to reference the byte.
I tried all sorts of things with var aliases and modifiers but couldn't hit on anything that worked.
Is there a better way?
Post Edited (George99) : 7/22/2006 7:27:47 PM GMT
I want to create an array of bits, i.e. bits VAR Bit(8), change bits as needed, then use the result as a byte.
This works:
' {$STAMP BS2}
' {$PBASIC 2.5}
bits VAR Bit(8)
bits(6)=1
bits(0)=1
debug B0 ' displays A
...but I really don't like using that B0 to reference the byte.
I tried all sorts of things with var aliases and modifiers but couldn't hit on anything that worked.
Is there a better way?
Post Edited (George99) : 7/22/2006 7:27:47 PM GMT
Comments
"Thou shalt never have enough COBOL, until thy hand falls off from a repititive use injury"!
EXACTLY one of the reasons I switched from applications programming to systems programming many decades ago.
The "B0 restriction" is ONLY required on the PBASIC Stamp BS-1, The BS-2 series permits individual addressment, or group addressment. This example happens to use a WORD variable, but the same technique can be used with a BYTE variable:
switches VAR Word
sw0 VAR switches.bit0
sw1 VAR switches.bit1
sw2 VAR switches.bit2
sw3 VAR switches.bit3
sw4 VAR switches.bit4
sw5 VAR switches.bit5
sw6 VAR switches.bit6
sw7 VAR switches.bit7
sw8 VAR switches.bit8
sw9 VAR switches.bit9
sw10 VAR switches.bi10
sw11 VAR switches.bit11
sw12 VAR switches.bit12
sw13 VAR switches.bit13
sw14 VAR switches.bit14
sw15 VAR switches.bit15
Also remember that ANY PBASIC variable can be addressed as an array. An array (per se) isn't really a special declaration. An example is shown below:
datum VAR WORD
datum(0) = 5
Is a legitimate reference to the first BYTE of datum. Remeber too all arrays start with index = 0!
I hope that helps.
Regards,
Bruce Bates
Post Edited (Bruce Bates) : 7/22/2006 8:56:15 PM GMT
sw0 VAR switches.bit0
.
.
.
sw15 VAR switches.bit15
So in this example I could refer to sw0(5) to get at sw5?
Edited to say I just tried it and it works. Thanks.
Happy to hear that! Any further assistance, just shout.
Bruce
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I've always been interested in uC's but somehow stayed unaware of the Basic Stamp. I realize there must be more powerful controllers out there, but I thought the BS was a good starting place once I found the kit with book and Homework Board in Radio Shack.
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