reg TESTB

[john]

Hi

Can anyone shed some light on TESTB. Wt for it is used..........


thanks

[jamief]

Re: reg TESTB

Testb (test bit Pattern) = compares the bits specified in factor 2 to the result field.
There are eight bits in a byte in EBCDIC.
Bits can be equal to either on ('1') or off ('0')

ex. if only bits 5 and 7 are on then the byte = X'05' (hex) and
B'00000101' and numeric value of 5

I have attached a PDF with some examples just open and search for testb.

[GLS400]

Re: reg TESTB

Hi John:

Back in the days of old I have used the testb combined with biton/bitoff to convert upper/lower case letters.

bit 1 on = upper case
bit 1 off = lower case

I have also used it to save user switches prior to calling an external program which may re-set the switches.


C bitoff '01234567' bit
C u1 biton '0' bit
C u2 biton '1' bit
etc.
C SETOFF U1U2U3
C SETOFF U4U5U6
C SETOFF U7U8 C call 'otherpgm'
C SETOFF U1U2U3
C SETOFF U4U5U6
C SETOFF U7U8
C TESTB '0' BIT U1
C TESTB '1' BIT U2
C TESTB '2' BIT U3
C TESTB '3' BIT U4
C TESTB '4' BIT U5
C TESTB '5' BIT U6
C TESTB '6' BIT U7
C TESTB '7' BIT U8


I think all will agree this is really old school and I haven't seen this type of coding in recent years