I'm still wrestling with this problem, but think I have found the cause 
(although not the solution).  To recap:

We have a Tally T6212 impact line printer (emulating an HP2564C).  On 
our HP3000/A500 MPE 7.5 it worked fine with the NPCONFIG entry:

> 6 (network_address = 192.168.126.2
>    pjl_supported = FALSE
>    setup_file = NOTHING.HPENV.SYS
>    serial_printer_simulation = TRUE
>    jam_recovery = FALSE)

On our new HP3000/N4000 MPE 7.5, it does not.  The following behavior is 
different:

* A hard reset is being sent to the printer at the beginning of every 
print job.  This resets any changes the operator makes for forms (e.g., 
6LPI/8LPI).

* The system sends PJL setup sequences to the printer at the beginning 
of every print job:

> @PJL
> @PJL RESET
> @PJL ENTER LANGUAGE=PCL 

I've tried 'snmp_supported = FALSE' and even the new 'pcl_enabled = 
FALSE' to no avail.  The latter is tied to MPEMXU1 (see 
http://jazz.external.hp.com/papers/Communicator/7.5/NWPrinting.html) and 
therein lies the problem, I believe, as the A500 does not have this patch.

The A500 has:

> ACCOUNT=  SYS         GROUP=  PUB     
>
> FILENAME  CODE  ------------LOGICAL RECORD-----------  ----SPACE----
>                   SIZE  TYP        EOF      LIMIT R/B  SECTORS #X MX
>
> OUTSPTJ * NMPRG   128W  FB        1283       1283   1     1296  6  *

while the N4000 has:

> ACCOUNT=  SYS         GROUP=  PUB     
>
> FILENAME  CODE  ------------LOGICAL RECORD-----------  ----SPACE----
>                   SIZE  TYP        EOF      LIMIT R/B  SECTORS #X MX
>
> OUTSPTJ * NMPRG   128W  FB        1299       1299   1     1312  6  *

I tried copying the A500's version over as OUTSPTJO and including 
"program_file = OUTSPTJO.PUB.SYS" in NPCONFIG, but the spooler complains 
that the "program file must be OUTSPTJ.PUB.SYS or /SYS/PUB/OUTSPTJ", so 
there's no trying that workaround.

Is there a clever way to "unpatch" MPEMXU1 ?  Will simply replacing the 
program file via an UPDATE do it, or were there related system segments 
involved as well?

Or am I barking up the wrong tree altogether?

Jeff

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