Seymour,
this citation is about what ED does with left and right nibbles, but it
does not contradict what I cited (or said)
I say it again in my words:
left nibbles must be numeric- right can be anything.
This is true for all bytes subject to EDiting
Martin
Am 24.02.26 um 22:07 schrieb Seymour J Metz:
"At the time the left digit of a source byte is examined,
the rightmost four bits are checked for the existence
of a sign code. When a sign code is encountered in
the rightmost four bit positions, these bits are not
treated as a decimal-digit code, and a new source
byte is fetched from storage when the next pattern
byte calls for a source-digit examination."
--
Shmuel (Seymour J.) Metz
http://mason.gmu.edu/~smetz3
עַם יִשְׂרָאֵל חַי
נֵ֣צַח יִשְׂרָאֵ֔ל לֹ֥א יְשַׁקֵּ֖ר
________________________________________
From: IBM Mainframe Discussion List<[email protected]> on behalf of Martin
Trübner<[email protected]>
Sent: Tuesday, February 24, 2026 12:25 PM
To:[email protected] <[email protected]>
Subject: Re: ED fail to generate 0C7
External Message: Use Caution
Seymour,
this is what it says:
The leftmost four bits of each source byte must specify a decimal-digit
code (0000-1001); a sign code (1010-1111) is recog-
nized as a general-operand data exception. The
rightmost four bits may specify either a sign code or a
decimal-digit code.
Martin
Am 24.02.26 um 16:38 schrieb Seymour J Metz:
No, that's not what Pops says. The left nybble must be a valid digit and the
second nybble gives different results depending on whether it is a digit or a
sign.
--
Shmuel (Seymour J.) Metz
http://mason.gmu.edu/~smetz3
עַם יִשְׂרָאֵל חַי
נֵ֣צַח יִשְׂרָאֵ֔ל לֹ֥א יְשַׁקֵּ֖ר
________________________________________
From: IBM Mainframe Discussion List<[email protected]> on behalf of Martin
Trübner<[email protected]>
Sent: Tuesday, February 24, 2026 4:17 AM
To:[email protected] <[email protected]>
Subject: Re: ED fail to generate 0C7
External Message: Use Caution
Second attempt- maybe this time readable
ED checks all left nibbles for num, the right nibble is not checked, but
interpreted (digit select, field separator , etc).... see POP.
so 12 3A 56 7B as 4 char packed field is valid (ED does not care for single
field or multiple fields).
12 A3 45 67 is not valid because the second left nibble is not numeric
Martin
Am 23.02.26 um 20:48 schrieb martin:
ED checks all left nibbles for num, the right nibble is not checked, but
interpreted (digit select, field separator , etc).... see POP.MartinFrom a
mobile, you can keep tpyos
-------- Ursprüngliche Nachricht
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send [email protected] with the message: INFO IBM-MAIN
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send [email protected] with the message: INFO IBM-MAIN
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email [email protected] with the message: INFO IBM-MAIN
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email [email protected] with the message: INFO IBM-MAIN
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to [email protected] with the message: INFO IBM-MAIN
