RE: Biton/Bitoff

["Shoaf, Jack" <jshoaf@xxxxxxxxxxxxxx>]

Each Byte consists of 8 bits identified reletive to Zero from left to
right.  Therefore bit one of a byte is Bit 0, Bit two is identified as
BIT 1 etc.   The Biton and Bitoff commands simply turn the bit
identified in the Factor two field on or off (depending on which command
you use) of the Byte idenfiled in the Result field, thereby changing the
value of the Result field.  

C               Bitoff  '01234567'      SS1   will turn all the 8 bits
off resulting in SS1 = Hex 00 or Binary=00000000
then if the line is executed w/ *IN 60 on :
C       60      Biton '0'               SS1  will = Hex 80 or Binary
1000000
then if the line is executed w/ *IN 61 on :
C       61      Biton '1'               SS1  will = Hex C0 or Binary
1100000

Setting bits on/off can be useful but you really need to have a chart to
cross-reference the binary values to hex or EDCDIC  representation to
know what your changing it to. I don't know what your program is trying
to acheive from your example but hope this helps. 

One use I had found for Biton/Bitoff commands in earlier versions of RPG
was to issue BITON '1' for each Byte in an alpha field which would
result in switching any letter in the field to uppercase. BITOFF'1'
would conversely change them to lowercase. There are better ways to do
this now however.   



> +++++++++++++++++++++++++++
> 
> Jack Shoaf
> Director of MIS
> The Echo Design Group, Inc
> 1050 Valley Brook Avenue
> Lyndhurst, NJ 07071
> 
> Phone: 201-842-0088
> Fax     : 212-686-5017
> E-mail : Jshoaf@echodesign.com
> 
> -----Original Message-----
> From: Scott Swaim [SMTP:scott71@hpnc.com]
> Sent: Friday, March 20, 1998 4:14 PM
> To:   MIDRANGE-L@midrange.com
> Subject:      Biton/Bitoff
> 
>         Never having programmed the to opcodes, What are they?  That
> do they do?
>  
> Please explain what is happening with this code.
>  
>  
> C                                 BITOFF     '01234567'         SS1   
> 1
> C           60                 BITON       '0'                        
> SS1
> C           61                 BITON       '1'                        
> SS1
>   
>  
>  
>  
> TIS
>  
>  
>  
> Scott Swaim
> scott71@hpnc.com <mailto:scott71@hpnc.com> 
> http://www.qualitycorps.com 
>  
+---
| This is the Midrange System Mailing List!
| To submit a new message, send your mail to MIDRANGE-L@midrange.com.
| To unsubscribe from this list send email to MIDRANGE-L-UNSUB@midrange.com.
| Questions should be directed to the list owner/operator: david@midrange.com
+---