Typcasting Variables inside of Arrays

[MOUNTAIN747]

Why is it that if I define variables by typcasting Variables inside of Arrays I can not use HighByte and LowByte on those variables? When I do, I get an error message that says "attempt to redefine (the variable)"?

[rsocor01]

This thread might help you

http://www.picbasic.co.uk/forum/show...ghlight=arrays

Robert

[MOUNTAIN747]

And there we have it!

Thanks Robert, It looks like I will be adding one more variable to the program.

[Darrel Taylor]

For more versatility, you might consider this ...

The EXT (external) modifier.

Typcasting Variables inside of Arrays
http://www.picbasic.co.uk/forum/show...php?t=3891#TYP

[MOUNTAIN747]

For more versatility, you might consider this ...

The EXT (external) modifier.

Typcasting Variables inside of Arrays
http://www.picbasic.co.uk/forum/show...php?t=3891#TYP

Darrel, EXT can't be that versatile. I'm using the EXT modifier, its your code example I'm using.

Serout2 TX_USB, 84,[" DSvolts is ",bin DSvolts.highbyte,bin DSvolts.lowbyte,13,10]
this won't compile. Should it? Or could I have a Bank problem?

    DSbuffer  VAR BYTE[9] BANK0
ASM          ;Typcasting Variables inside of Arrays
DSstat    = _DSbuffer      ; byte
DStemp    = _DSbuffer + 1  ; word
DSvolts   = _DSbuffer + 3  ; word
DScurrent = _DSbuffer + 5  ; word
DSthres   = _DSbuffer + 7  ; byte
DScrc     = _DSbuffer + 8  ; byte
ENDASM
    DSstat      VAR  BYTE  EXT ; Status/Configuration
    DStemp      VAR  WORD  EXT ; Temperature
    DSvolts     VAR  WORD  EXT ; Voltage
    DScurrent   VAR  WORD  EXT ; Current
    DSthres     VAR  BYTE  EXT ; Threshold
    DScrc       VAR  BYTE  EXT ; CRC

[Darrel Taylor]

PBP can't use HighByte and Lowbyte because it doesn't know where the variable is when PBP is compiling. The location isn't known until it's Assembled.

Try it like this, which specifies the High and Low bytes as EXT too.

    DSbuffer  VAR BYTE[9] BANK0
ASM          ;Typcasting Variables inside of Arrays
DSstat    = _DSbuffer      ; byte
DStemp    = _DSbuffer + 1  ; word
DSvolts   = _DSbuffer + 3  ; word
DSvoltsL  = _DSbuffer + 3  ; byte
DSvoltsH  = _DSbuffer + 4  ; byte
DScurrent = _DSbuffer + 5  ; word
DSthres   = _DSbuffer + 7  ; byte
DScrc     = _DSbuffer + 8  ; byte
ENDASM
    DSstat      VAR  BYTE  EXT ; Status/Configuration
    DStemp      VAR  WORD  EXT ; Temperature
    DSvolts     VAR  WORD  EXT ; Voltage
    DSvoltsH    VAR  BYTE  EXT
    DSvoltsL    VAR  BYTE  EXT
    DScurrent   VAR  WORD  EXT ; Current
    DSthres     VAR  BYTE  EXT ; Threshold
    DScrc       VAR  BYTE  EXT ; CRC


Serout2 TX_USB, 84,[" DSvolts is ",bin DSvoltsH,bin DSvoltsL,13,10]

[MOUNTAIN747]

Amazing!

Thanks Darrel.