BARR/RJE with PRINT370 can replace the Xerox 871 Communications Module (871-CM) for printing to Xerox Laser Printing System (LPS) devices. The 871-CM functions like an IBM 3777 remote workstation.
BARR/RJE with PRINT370 supports features that are not available with the 871-CM. Use the chart below to compare the features of the two printing solutions. In particular, note that PRINT370 supports printers with an S/390 channel interface, while the 871-CM supports only printers with the non-channel, Offline interface used with the Xerox Host Interface Processor (HIP) software.
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BARR/RJE with PRINT370 |
Xerox 871-CM |
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Printer requires Online (S/390 channel) printer interface |
Printer requires Offline (HIP) printer interface |
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Uses Barr S/390 or ASCII file format |
Uses ASCII file format |
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Supports Printer Carriage Control (PCC) or channel stops |
Converts PCC to carriage return (CR), line feed (LF), and form feed (FF) |
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Drives up to six printers |
Drives a single printer |
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Supports communications line speeds up to T1 (1.536 Mbps) or E1 (2.048 Mbps) |
Supports communication line speeds up to 56 kbps |
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Supports DATMODE=FULL or DATMODE=HALF |
Uses DATMODE=HALF |
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Supports MAXDATA of up to 1033 bytes |
Supports MAXDATA of up to 521 bytes |
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Simultaneously prints and receives data |
Cannot receive data while printing |
When you replace an 871-CM with a PC, BARR/RJE, and PRINT370 software, you must make a few adjustments to the printer and the mainframe.
The Xerox printer representative must make the following changes to the Xerox printer:
Replace the Offline interface and HIP used with the 871-CM with an Online (or S/390 channel) interface.
Change the Job Source Library (JSL) to work with the Online interface.
You must place the Xerox printer in Online mode to print data received on the S/390 channel interface. For example, you must use the channel interface when the printer is directly attached to the mainframe or attached to a PC running PRINT370.
Because the 871-CM and PRINT370 use different interfaces, they also require different JSLs in the printer. JSLs contain the text source statements to describe how the printer will input print data and output the image on paper. The Print Description Language (PDL) compiler converts the JSL into a Job Descriptor Library (JDL), which the printer references at receive and print time. The JSL varies depending on the printer’s features. For example, PCC commands are valid for Offline mode but invalid for Online mode.
Xerox normally supplies the file ONLINE.JSL with the Online printer interface. You can customize this file to suit your needs or you can modify a JSL you used with the 871-CM to work with the Online interface.
If you modify an existing JSL, you might need to adjust some position-dependent statements. These statements are affected by the different ways the 871-CM and the Barr software handle channel commands. The 871-CM sends a channel command and data to the printer as a single record. The PRINT370 software sends the channel command first, and then sends the data record, so data records appear to be one column shorter than they would be on the 871-CM. (The PRINT370 method more closely mimics mainframe-attached printing.) As a result, you must reduce the column position by one in commands such as the DATA statement, IDEN prefix, FONTINDEX, and any commands that use the CRITERIA statement. You also must change the HOST and PCC statements. Consult your Xerox printer representative for guidance.
BARR/RJE with PRINT370 and the Xerox 871-CM both support print data streams and punch data streams. However, for most RJE systems, you should use Barr software with print streams. Print streams can transport records longer than the default punch width of 80 bytes. Many print output files contain 132-character records and thus require the longer data stream. Print streams also can compress and compact data, which improves data throughput.
Refer to the systems documentation for your host RJE system or consult your mainframe systems programmer to determine if you should use a print stream or punch stream.
VSE/POWER: The VSE/POWER job entry system does not support transparency on the print stream. Use the punch stream if you print non-text data, such as Xerox Metacode.
Jobs at the mainframe usually are tailored to work with the 871-CM, which supports only ASA and machine carriage control. Because the Barr software and the 871-CM handle carriage control differently, you might need to adjust format information at the mainframe or in the Barr software when you replace the 871-CM.
You have two choices for handling data you previously printed with an 871-CM. Which method you use depends on the format of the mainframe data.
For mainframe jobs with machine carriage control, you do not need to change format information at the mainframe. Use the 871-CM’s JCL format, which specifies no carriage control, and set the Barr software Carriage control option to Machine (discards SCS carriage control).
For mainframe jobs with ASA carriage control, you must change the format information at the mainframe. Change the JCL format to specify the correct carriage control and set the Barr software Carriage control option to normal (converts SCS carriage control to machine carriage control). Barr PRINT370 does not support ASA carriage control.
If you receive some files with machine carriage control and other files with ASA carriage control, you must use a different print stream for each carriage control type because the Barr software requires different carriage control settings for each type.
If you are not familiar with the JCL format of the files at the mainframe, try receiving a file from the mainframe with Carriage control set to normal. If the file does not print correctly, try printing it with Carriage control set to Machine. For more information about these methods, see the rest of this section.
For this discussion, keep in mind the factors that affect data format when a file is transferred from the mainframe to the PC.
Mainframe format – Files at the mainframe usually have a machine or ASA carriage control byte as the first character of each record.
JCL format – JCL statements specify the record format of the file to be sent to the remote. For example, RECFM=FBM indicates the file contains fixed-length records with machine carriage control.
JES format – The job entry system (JES) determines the file format from the JCL. Then, it converts machine or ASA carriage control to equivalent SCS carriage control characters and transfers the data to the remote. For files that do not have carriage control, JES simply inserts record separators.
Barr format – The Carriage control option for the S/370 Channel receive mode controls whether the software converts the SCS carriage control to machine carriage control (Carriage control: normal) or discards the SCS carriage control (Carriage control: Machine).
Remote job entry systems, such as JES, convert ASA and machine carriage control to SCS carriage control when they transfer data to a remote printing system. But the 871-CM cannot process SCS carriage control, so a method was devised to preserve the ASA and machine carriage control for the 871-CM. To prevent JES from converting the ASA and machine carriage control, you must specify an incorrect record format in the JCL. For example, you would specify that data with machine carriage control does not have carriage control. As a result, JES treats the machine carriage control as another data byte and does not convert the carriage control to SCS. The embedded machine carriage control byte is transferred to the remote with the data (see Figures 6-1 and 6-2).
Figure 6-1. A mainframe job with machine carriage control (M) is routed to the 871-CM. Because the JCL record format specifies no carriage control, JES adds an SCS record separator (S) and treats the machine carriage control as data. The 871-CM discards the SCS byte and uses the machine carriage control.
Figure 6-2. A mainframe job with ASA carriage control (A) is routed to the 871-CM. Because the JCL record format specifies no carriage control, JES adds an SCS record separator (S) and treats the ASA carriage control as data. The 871-CM discards the SCS byte and uses the ASA carriage control.
Data in this format is not what BARR/RJE with PRINT370 usually expects, but you can set up the Barr software to accept the embedded machine carriage control. For ASA carriage control, however, you must make other adjustments.
Machine Carriage Control – For machine carriage control, you can set up the PRINT370 software to use the 871-CM data format without making JCL changes at the main-frame. On the Assign Devices screen, select S/370 Channel receive mode and set Carriage control to Machine. This tells the software that the data contains embedded machine carriage control. The software discards the SCS carriage control and recognizes the first data byte as machine carriage control.
Figure 6-3. For a mainframe job with machine carriage control (M), set carriage control to machine in the Barr software to discard the SCS carriage control (S) and use the embedded machine carriage control (M).
ASA Carriage Control – PRINT370 does not support ASA carriage control, so you cannot use the incorrect JCL to embed the ASA carriage control as data. Instead, you must change the JCL format at the mainframe to correctly reflect the mainframe data format. Also, on the Assign Devices screen, select S/390 Channel receive mode and set Carriage control to normal. JES converts the ASA carriage control to SCS carriage control, and the Barr software converts the SCS carriage control to machine carriage control.
Figure 6-4. For a mainframe job with ASA carriage control (A), set the JCL to the correct format at the mainframe and set carriage control to normal in the Barr software. Barr software converts SCS carriage control (S) to machine carriage control (M).