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1.1 root 1: '\" t
2: .TH EM3280 8 DLBA 1.5
3: \" @(#)em3280.8 1.5
4: .SH NAME
5: em3280 \- IBM 328X Printer Emulation
6: .SH SYNOPSIS
7: .nf
8: .I
9: /usr/bin/em3280
10: .I
11: /usr/lib/bsc/bsclog
12: .I
13: /usr/lib/bsc/bscmon
14: .I
15: /usr/lib/bsc/bsctrace
16: .fi
17:
18: .SH DESCRIPTION
19: Em3280 is the communal name for the collection of programs and a file
20: organization that allows a computer system to communicate emulating an IBM
21: 328x printer. Together with a Bisync communications facility,
22: .I em3280
23: can emulate an IBM 3284, 3286, 3287, or 3288 printer.
24: The communications facility itself emulates the functions of the IBM 3271
25: communications control unit to which the 328x printer is usually attached.
26: .P
27: The Binary Synchronous protocol, commonly called BISYNC, is a byte-oriented,
28: half-duplex protocol, although full-duplex communications facilities
29: are sometimes used in order to reduce the time required to turn the
30: transmission direction around. A set of control characters are used
31: to provide framing and data transparency; data containing imbedded
32: control characters may be transmitted in a "transparent" mode to
33: avoid conflicts with the protocol control characters.
34: (The IBM 328x printer does not use the "transparent" mode.)
35: Communications may be point-to-point, in which case a contention
36: method is used to control the line; communications may also be multi-point,
37: in which case one node is designated the controlling node and polls
38: and/or selects the other nodes in order to control communications. The
39: IBM 328x printer is commonly used only in conjunction with multi-point
40: BISYNC communications facilities.
41: .P
42: In the em3280 system, the administrator designates a collection of
43: one or more hosts to which the computer connects emulating an
44: IBM 328x printer. For each of these hosts, the administrator provides
45: a set of parameters pertaining to that host connection and the specific
46: printer parameters for emulation.
47: .P
48: Users may direct em3280 output to stdout, directly to a file or device
49: (e.g. /dev/lp), or to a program (e.g. lpr).
50: Four print formats are supported: fixed at 40, 64, or 80 characters per line,
51: and variable-length, the data having newlines and other
52: format effectors imbedded in it.
53: .P
54: An audit trail can optionally be kept which records all em3280
55: activity. The audit trail logs host, user, and time for various messages
56: about connection and disconnection,
57: various statistics and all errors, temporary or permanent.
58: Once started, the audit trail file grows indefinitely; the administrator
59: is responsible for trimming it back when necessary.
60: .P
61: The following diagram shows the relationships between various files
62: and programs used in the 328X emulation process.
63: .TS
64: box,center;
65: c|c|c.
66: DESIRED USER LINK
67: FUNCTION LEVEL LEVEL
68: _
69: Emulate 328x em3280 /dev/bsc*
70: _ _ _
71: Check status bsclog <dir>/AUDIT
72: _
73: Monitor bscmon, /dev/bsctr*
74: Activity bsctrace
75: .TE
76: .P
77: The
78: .I <dir>
79: designator refers to the host's spool directory. This name is a combination of
80: the directory prefix "/usr/spool/bscbatch/"
81: followed by the <hostname> directory into which the AUDIT file
82: pertaining to this host will be placed.
83: .P
84: At the beginning of a session (user invokes
85: .I em3280)
86: the utility will read the host parameter file to determine the communications
87: line characteristics \- device to use, terminal identification, ...
88: and the printer parameter file to determine printer characteristics \-
89: output type (file or program), printer type (3284, 3286, ...),
90: ....
91: The communications line will be opened and the printer's characteristics
92: noted. As files are received from the host, they will be formatted according
93: to those characteristics and the output sent to either a user-specified
94: destination (file, device, or program), or stdout if no destination was
95: specified.
96: .P
97: When receive timeout is detected, the printer output device or file will be
98: closed, then re-opened to flush whatever output has been spooled so far.
99: .P
100: The session is terminated when the daemon detects that the host has dropped
101: the data set ready signal. At that point, connection with the host has been
102: terminated. The installation may provide an exit routine to be invoked at this
103: time (immediately after termination of connection) to take care of
104: any necessary cleanup.
105: .P
106: A trace facility can be invoked which records communications events
107: and the time they occur,
108: and optionally records actual data, transmitted and received. The
109: trace information can be placed into a file for immediate or later
110: analysis by another program.
111: The general intent is to provide enough information for communications
112: debugging that a data link analyzer is not necessary.
113: .P
114: The
115: .I bsctrace
116: program interprets trace information provided to
117: .I bscmon
118: by /dev/bsc*tr. A state diagram provided with the
119: .I bscmon(8)
120: document shows the communication
121: states and flow which makes up the BISYNC protocol; state transition
122: information is provided to
123: .I bscmon,
124: which records
125: it and optionally the transmitted and received data, in a file.
126: .I Bsctrace
127: is used to display this data in a readable format.
128: .SH ADMINISTRATION
129: .SS Installation.
130: The em3280 tape is used in the installation process for the em3280
131: facility. To install em3280, do the following:
132: .RS
133: .IP 1.
134: Make a directory to contain the installation files, e.g.,
135: /tmp/em3280, then change to that directory. Use
136: .I tar xov0
137: to copy the files from tape to the directory.
138: The following files should be extracted:
139: .TS
140: center;
141: c c c.
142: em3280 em3280.x empr.h
143: 3280 3280inst inst3280.c
144: .TE
145: .IP 2.
146: Prepare installation exit subroutines, if necessary.
147: File inst3280.c contains default
148: subroutines for the installation exits, as described below. They
149: may be modified or completely replaced, but must exist.
150: .RS
151: .P
152: .I
153: connect (host, dev)
154: .br
155: .I
156: char *host, *dev;
157: .P
158: is called when
159: .I em3280
160: is ready to make a connection to
161: .I host
162: via device
163: .I devname.
164: The connection will be made only if
165: .I connect
166: returns a zero value; if a non-zero value is returned, a note will be placed
167: in the AUDIT file (if one exists), and
168: .I em3280
169: will terminate.
170: .P
171: This routine may perform operator communication
172: necessary for connection. The default (supplied) routine merely
173: returns a zero value immediately.
174: .P
175: .I
176: disconnect (host, devname)
177: .br
178: .I
179: char *host, *devname;
180: .P
181: is called when
182: .I em3280
183: has just disconnected from the given host and device.
184: This routine may perform any cleanup necessary
185: at this time. The default (supplied) routine merely returns.
186: .P
187: .I
188: audit (message)
189: .br
190: .I
191: char *message;
192: .P
193: is a routine which may be called by any of the installation-supplied
194: routines which need to place information into the AUDIT file. The
195: single parameter will be written into the AUDIT file along with a
196: time stamp and the current host's name.
197: .RE
198: .IP 3.
199: Install all files. "3280inst" is a shell command file which will
200: link the em3280 command object file with inst3280.c and
201: install all commands and files into the appropriate directories.
202: .RE
203: .SS "Set Up Host Configurations."
204: For each separate host, a file must be created in /usr/lib/bscbatch
205: which supplies the control and administrative information used by
206: em3280. The file may be created via the text editor.
207: Sample configurations appear in file 3280, extracted in step 1 above.
208: Any of the following parameters may be specified in the configuration
209: file, one parameter per line. The default will be taken for any unspecified
210: parameters.
211: .TP
212: CODE=ASCII|EBCDIC.
213: This specifies the transmission code
214: to be used in the protocol, and what translation is to be performed
215: on transmitted or received data.
216: Default: EBCDIC.
217: .TP
218: DEVICE=/dev/bsc*.
219: The device to be used for BISYNC operations must be specified here.
220: Default: /dev/bsc.
221: .TP
222: DUPLEX=HALF|FULL.
223: Specify FULL for a full-duplex modem, HALF for a half-duplex modem.
224: Default: HALF.
225: .TP
226: LINESPERPAGE=lines
227: Specify the number of lines to be printed on a page.
228: Default: 60.
229: .TP
230: MAIL=userid.
231: .I Em3280
232: will send mail to the system administrator (name given by
233: .I userid)
234: for any significant problems requiring attention.
235: These include incorrect parameters in this file,
236: inability to connect to host, and host id check failures.
237: Default: messages sent to /dev/console.
238: .TP
239: MPTADDR=aa.
240: .I Aa
241: is the address of the emulated printer if this is a multipoint network.
242: If this is point-to-point, this parameter must not be specified.
243: .I Aa
244: consists of two alphabetic characters. The first is the polling address,
245: the second the select address.
246: Default: poll address=0x40, select address=0x60.
247: .TP
248: NBID=nn.
249: .I Nn
250: is the number of initial handshakes,
251: or "line bids" which will be made when there is no host response.
252: In a multipoint or other leased line arrangement, this value should
253: be zero, which means retry forever.
254: Maximum value for
255: .I nn:
256: 255.
257: Default: 0 (no limit).
258: .TP
259: NNAK=nn.
260: .I Nn
261: specifies the number of NAK's (negative
262: acknowledgement to text block due to CRC error) that the driver should
263: give before terminating communications via sending EOT instead of
264: NAK. This parameter prevents endless transmissions for cases where
265: the text block was actually built incorrectly.
266: Maximum value for
267: .I nn:
268: 255.
269: Default: 16.
270: .TP
271: NRETRY=nn.
272: .I Nn
273: is the number of retries which will
274: be made during transmission where a text block has been NAK'd (received
275: with incorrect CRC, or check characters) or where a text block has
276: had no response from the host (timeout).
277: Maximum value for
278: .I nn:
279: 255.
280: Default: 15.
281: .TP
282: NTTD=nn.
283: .I Nn
284: is the number of TTD's (temporary
285: text delays from host) that the driver should receive and NAK before
286: terminating the receive operation via sending EOT. This parameter
287: may be used to prevent prolonged delays from tying up a communications
288: line. A value of zero will force the driver to always NAK a TTD.
289: Maximum value for
290: .I nn:
291: 255.
292: Default: 150.
293: .TP
294: NWACK=nn.
295: .I Nn
296: is the maximum number of WACK's (wait
297: acknowledgements) the driver will accept while attempting to transmit
298: before terminating transmission via sending EOT. This parameter may
299: be used to prevent prolonged delays while the host computer is unable
300: to accept the next data block due to delays.
301: A value of zero will force the driver to always accept a WACK.
302: Maximum value for
303: .I nn:
304: 255.
305: Default: 150.
306: .TP
307: OUTPUT=P|F,destination
308: Specify whether output will be written to a file (F), or piped to a program (P),
309: and the name of the file or pipe.
310: Default: P,lpr.
311: .TP
312: PTYPE=4|6|7|8|9
313: Specify the type of IBM 328x printer being emulated; 4=3284, 6=3286, etc.
314: Default: 4.
315: .TP
316: TIMEOUT=nnn
317: If there are no files to be sent to the current host, and there is no
318: activity from the host (no files being received from the host) for
319: .I nnn
320: seconds,
321: .I bscd
322: will disconnect.
323: Default: 30.
324: .TP
325: TPRINT=YES|NO.
326: Specifiy whether the IBM text print option, available only on 3288 printers,
327: will be used.
328: Default: NO.
329: .SS "Set Up Host SPOOL Area."
330: For each host, make a directory /usr/spool/bscbatch/<hostname>.
331: If an audit trail is to be kept on this host, create an empty file
332: in that directory called AUDIT.
333: .SS "Regular Maintenance."
334: .P
335: Some minimal maintenance of the host spool areas is required.
336: The administrator's mailbox should be inspected and cleaned out regularly.
337: The audit trail file (/usr/spool/bscbatch/<hostname>/AUDIT) should be truncated
338: via the
339: .I bsclog
340: utility regularly.
341: Most convenient is an entry in crontab \- once per day,
342: .I
343: bsclog -purge=3
344: could be run to discard all but
345: AUDIT information for the last three days (see
346: .I bsclog(8)).
347: .SH "SEE ALSO"
348: .br
349: em328x(1C) - 328x printer emulator
350: .br
351: bsclog(8) - batch audit trail utility
352: .br
353: bscmon(8) - bsc monitor/trace utilities
354: .br
355: .I
356: Setting Up UNIX
357: .br
358: .I
359: General Information - Binary Synchronous Communications,
360: IBM document GA27-3004.
361: .br
362: .I
363: 3270 Component Description,
364: IBM document GA27-2749.
365: .SH "SYSTEM REQUIREMENTS"
366: .SS Modems.
367: If two identical modems (same manufacturer, same options)
368: are used at each end of the communications line, most any synchronous
369: RS-232-C interface modem will function correctly. The following modems
370: are definitely supported:
371: .P
372: .nf
373: Bell 201A3 (2000 bits per second)
374: Bell 201C (2400 bits per second)
375: Bell 208B (4800 bits per second)
376: Bell 209A (9600 bits per second)
377: .fi
378: .SS Hardware.
379: This software is supported when used with the following:
380: .P
381: .nf
382: UNIX Version 7, System 3, or System 5 operating system
383: MODEM port jumpered for external clocking
384: MODEM port jumpered as Data Terminal Equipment
385: .fi
386: .SH DIAGNOSTICS
387: .P
388: em3280 <host>: can't open <confdir> configuration directory.
389: .IP
390: The configuration directory for this host couldn't be opened.
391: Check the modes. Processing was aborted.
392: .P
393: em3280 <host>: <devname> cannot be opened for communications.
394: .IP
395: The communications device <devname> for the specified
396: host could not be opened. Either the mode is set wrong, or some other
397: process has the device open. Processing was aborted.
398: .P
399: em3280 <host>: unrecognized keyword, line <l> in <filename>.
400: .IP
401: While reading the host configuration file <filename>,
402: an unrecognized keyword was found on line <l>. Probably a typographical
403: error. Processing was aborted.
404: .P
405: em3280 <host>: invalid parameter for keyword <k> in <filename>.
406: .IP
407: While reading the host configuration file <filename>,
408: keyword <k> was found to have an invalid parameter. Probably a typographical
409: error, but it is also possible that the given parameter was out of
410: range. Processing was aborted.
411: .P
412: em3280 <host>: device <devname> reports modem failure.
413: .IP
414: The named device reported a transmit timeout error. The usual reason
415: for this is that the device did not get a transmit clock signal from
416: the modem. This could be due to improper modem option specification,
417: improper cable to the modem from the computer system, or to not having
418: jumpered the MODEM port for external timing. Transmission is
419: aborted for this host.
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