CICS terminal interface
Overview
The CICS (Customer Information Control System) interface causes a CICS terminal to appear to be a Model 204 terminal. Using the CICS interface introduces changes to the usual responses and mode of operation of a CICS-owned terminal. These changes vary according to the type of terminal and the type of CICS interface.
This topic summarizes terminal operation particulars for the CICS interface end user.
Terminals supported
The CICS interface supports the use of:
- IBM 3270 and compatible terminals
- Teletypes and Teletype-compatible terminals
Each of these terminals provides slightly different capabilities, responses, and default parameter settings. The information supplied for these terminals in Using SNA Communications Server terminals does not necessarily apply when the terminals are used through CICS.
Host language applications
Some host language application programs that communicate with Model 204 through the IFAM interface can be run as CICS transactions. Refer to the Rocket Model 204 Host Language Interface Reference Manual and the CICS system documentation for information about using host language application programs.
Selection of terminal support mode
Two modes of CICS support are available to Model 204 users of IBM 3270 terminals: full-screen and line-at-a-time. Full-screen terminals allow the entire screen to be formatted and displayed as a single entity while line-at-a-time terminals print all screen inputs and outputs on a line-by-line basis.
To select the desired mode for an installation, your system manager must do the following:
- Assemble, link-edit, and install the appropriate CICS transactions.
- Set the IODEV parameter on the user's parameter line for the terminal, specifying 11 for full-screen CICS usage and 29 for line-at-a-time.
For more information about these system manager actions, see the Rocket Model 204 installation instructions for your operating system. See also Defining the user environment (CCAIN).
Much of the information in this topic is presented according to terminal IODEV setting. IODEV 11 terminals are full-screen and IODEV 29 terminals are line-at-a-time. For the general features of full-screen and line-by-line terminal processing, see Terminal processing.
Note: If CICS cannot establish a connection for full-screen usage, the interface attempts to establish a line-at-a-time (sequential) connection, as described in When full-screen login fails. The decision whether or not to attempt a line-at-a-time connection depends on the configuration of the full-screen interface. For more information about this configuration, see your system manager.
Additional print capabilities
In addition to print capabilities described in this topic, the DEFINE PRINTER and USE PRINTER commands also can be used to direct output to CICS 328x- and TTY/TWX-type printers.
Invoking and disconnecting from the CICS interface
The steps required for logging in to Model 204 through the CICS interface and for disconnecting from the CICS interface are described in this section.
Getting online
To connect to Model 204 using a CICS system interface, first log in to CICS. Check with your system manager for the login procedures defined at your site.
Invoke the Model 204 CICS interface by entering one of the following commands, according to your terminal mode:
- For line-at-a-time mode, enter:
transid channelid
Where:
transid Identifies the CICS transaction for M204CIUL. Check with your system manager for the name of the transaction ID for your installation. L204is the default.channelid The CRAM channel to be used for the connection. The default channel name is M204PROD. - For full-screen mode, enter:
transid [[CHANNEL] channelid] [DATA input1; input2; ...]
Where:
transid The name of the CICS transaction for M204PSFS. Contact your supervisor for the name of the transaction ID for your installation. M204is the default.CHANNEL A keyword that must be specified if the channel ID is one of the following values: CHANNEL, TERMOFF, TERMON, or DATA. channelid The name of the CRAM channel to be used for the connection. The default channel name is M204FULL.DATA Specifies that input follows. The input is a series of input stream items that are passed to Model 204 after the connection is made. These items, separated by a semicolon, are processed by Model 204 as though each were an individual line of input from the terminal.
For example:
M204 TESTCHNL DATA LOGON userid;password;O USERFILE;I USERMENU
The terminal output that results from the transmission of the input stream items to Model 204 is not displayed. That is, the Model 204 output messages resulting from the logon, the password prompt, and the file open sequence are not displayed. The terminal output resulting from the last input stream item (that is, input) is always displayed.
When full-screen login fails
If a 3270 user attempts to log in to CICS with a full-screen connection and none is available, the user might be prompted to use the line-at-a-time interface. Whether or not this prompt is issued depends on the configuration of the full-screen interface. If so prompted, the user can also select an alternate channel name for the line-at-a-time interface.
If the interface responds with any other message, control automatically returns to CICS. Refer to the Rocket Model 204 messages documentation for a detailed description of CICS interface messages.
Disconnecting
To disconnect from the CICS interface, follow these steps:
-
Log out of Model 204 in the usual way by entering either:
LOGOUT
or:
LOGOFF
Model 204 closes any open files and displays the user ID, account, date, and time. - If full-screen 3270 CICS support is available, control automatically returns to CICS. Otherwise, to end the CICS transaction, enter:
*DISCONNECT
The interface releases the connection and displays the message:
MODEL 204 CONNECTION TERMINATED M204 TRANSACTION ENDING; RETURNING TO CICS
Control then returns to CICS.
IBM 3270 terminals (IODEV=11)
This section summarizes the information needed to use IBM 3270s (and compatible terminals) operating in full-screen mode under CICS.
Input lines
CICS users can use the full-screen input features, described in Full-screen formatting, which allow the entire screen to be formatted and displayed as a single entity. The user normally responds to prompts that are displayed on the screen. When the entire screen has been filled in, the user presses the ENTER key and the data is transmitted from the terminal to Model 204 for processing.
Program Function (PF) keys are supported by Model 204 only when you access a screen formatted through the SOUL full-screen formatting feature. Otherwise, PF keys are not supported and cannot be used to enter data. Any line entered by means of a PF key is considered null, and any data entered is lost.
Attention key
The PA1 key serves as the attention key on IBM 3270 terminals, unless you have reassigned the attention key through the FSATTN parameter.
Screen-formatting parameters
The screen-formatting parameters listed in the following table apply to IBM 3270 terminals being used through CICS.
The PGSEP parameter is not listed because it is not used with IBM 3270 terminals.
| Parameter | Meaning |
|---|---|
| INMRL | Maximum input line length for terminal |
| INCCC | Input continuation column |
| LOUTPB | Length of output page buffer |
| OUTMRL | Maximum output line length for terminal |
| OUTCCC | Output continuation column |
| OUTLPP | Number of lines per page, including headers and trailers |
| MODEL | Array of screen size parameters for the particular 3270 model |
| HDRCTL | Page formatting options |
The values of the first five parameters, which determine the size of the screen, are established by the value of the MODEL parameter, which corresponds to the terminal model within the 3270 family. Model 204 automatically sets MODEL to the appropriate value for SNA Communications Server (formerly VTAM) 3270s used through CICS, but the user also can reset it.
Terminal model options
The following table shows the valid settings for MODEL, the corresponding terminal type, and the corresponding default values for the screen size parameters. The user can reset INCCC and OUTCCC to override the default values established by the MODEL parameter.
| MODEL | INMRL | INCCC | OUTMRL | OUTCCC | 3270 terminal type |
|---|---|---|---|---|---|
| 1 | 78 | 78 | 80 | 80 | Model 1 |
| 2 | 78 | 78 | 80 | 80 | Model 2 |
| 3 | 78 | 78 | 80 | 80 | Model 3 |
| 4 | 78 | 78 | 80 | 80 | Model 4 |
| 5 | 130 | 130 | 132 | 132 | Model 5 |
Output page buffer settings
The MODEL parameter is reset only if the size of the output page buffer (LOUTPB) is large enough to hold the new screen size.
The minimum LOUTPB settings are shown in the following table.
| MODEL | LOUTPB |
|---|---|
| 0 | 1170 |
| 1 | 1170 |
| 2 | 2130 |
| 3 | 2770 |
| 4 | 3650 |
| 5 | 3774 |
Page header formats
HDRCTL consists of a series of switches that control the formatting of pages transmitted to the terminal. Each switch can be set independently of the others.
HDRCTL is not usually reset, but it can be reset to the following values for 3270 terminals:
| 0 | Normal headers (system header showing date, time, and page number) |
|---|---|
| 1 | Suppress header 0 (system header showing date, time, and page number) |
| 2 | Suppress the blank line that normally follows header 0 for nonrequest output |
Pausing and canceling output
At the end of each page of output, Model 204 pauses to allow the user to read the contents of the screen or to cancel the current request if too much output is being received. A prompting greater than sign (>) is displayed, indented 25 spaces on the last line of the screen.
Valid user responses are:
- Press Enter. The terminal goes on to the next page.
- Press the attention key or enter *CANCEL, C (cancel), or K (kill), followed by Enter. Unless an ON ATTENTION statement is in effect (see Attention interrupt feature), the current output and request are canceled.
- Enter a backpage request. (See Backpaging.)
- Enter the next input line, which cannot exceed 53 characters. The cursor moves as the user keys, to indicate the number of spaces used.
As discussed in Pausing, be aware that only one line of anticipatory input can be entered at this time. Also, if the terminal reaches the end-of-page pause for the next page of output, the saved input line is lost.
Canceling the current request
You can cancel the evaluation of the current Model 204 SOUL request by pressing the attention key in the following instances:
- If the terminal is waiting for input
- If Model 204 is waiting for input from the terminal or is actively displaying output on the terminal
Note: If Model 204 is compiling or executing a command, you cannot cancel the operation by pressing the attention key.
CICS printer
The contents of a 3270 screen can be routed to a printer in the CICS network by pressing the PA2 key.
If you press PA2, Model 204 prompts with:
COPY SCREEN (Y/N)? Y WITH PRINTER ID = xxxx
You must enter the 4-character terminal identifier that has been assigned to the selected printer. If you enter an invalid printer ID or enter three consecutive null responses (press Enter three times without keying any data), the interface displays:
PRINTER ID INVALID - RE-ENTER COPY SCREEN (Y/N)? Y WITH PRINTER ID = xxx
PRINTER ID INVALID - RE-ENTER COPY SCREEN (Y/N)? Y WITH PRINTER ID = xxx
If you answer Y, the interface prompts again for the printer ID. If you answer N, the interface continues to the next page, ignoring the previous print request.
IBM 3270 terminals (IODEV=29)
This section summarizes the information needed to use IBM 3270s (and compatible terminals) operating in line-at-a-time mode under CICS.
Output parameters
As soon as the Model 204 connection is made, the CICS interface sets the following output parameters to the default values shown in the following table.
| Parameter | Meaning | Default |
|---|---|---|
| OUTMRL | Maximum output line length for terminal | 72 |
| OUTCCC | Output continuation column | 72 |
| OUTLPP | Number of lines per page, including headers and trailers | 56 |
Pausing and canceling output
At the end of each page of output or after 23 lines have been displayed, the CICS interface pauses to allow you to interrupt Model 204 or to cancel the current request if too much output is being received. The CICS interface indicates that it is in pause mode by displaying the greater-than sign (>) prompt in the 25th column of the 24th line on the display screen.
Valid user responses are:
- Press the PA1 key. The current request or operation is canceled, the screen is erased, and the cursor is positioned at the beginning of the first line. Model 204 is then ready to accept terminal input from the user.
- Press the PA2 key. The current screen image is printed on a 3284 or 3286 hard-copy printer, as described in the section CICS printer.
- Press Enter or enter any other character (except C or P). The interface goes on to the next page.
CICS printer
The contents of the current 3270 screen can be routed to a printer in the CICS network by pressing the PA2 key.
If you press PA2, Model 204 prompts with:
COPY SCREEN (Y/N)? Y WITH PRINTER ID = xxxx
You must enter the 4-character terminal identifier that has been assigned to the selected printer. If you enter an invalid printer ID or enter three consecutive null responses (press Enter three times without keying any data), the interface displays:
PRINTER ID INVALID - RE-ENTER COPY SCREEN (Y/N)? Y WITH PRINTER ID = xxx
If you answer Y, the interface prompts again for the printer ID. If N, the interface continues to the next page, ignoring the previous print request.
Teletypes (IODEV=29)
This section summarizes the information needed to use Teletypes and compatible terminals operating under CICS.
Output parameters
As soon as the Model 204 connection is made, certain output conventions are established for Teletypes, and compatible terminals. The CICS interface sets the parameters in the following table to the default values shown.
| Parameter | Meaning | Default |
|---|---|---|
| OUTMRL | Maximum output line length for terminal | 72 |
| OUTCCC | Output continuation column | 72 |
| OUTLPP | Number of lines per page, including headers and trailers | 56 |
Pausing and canceling output
At the end of each page of output, the CICS interface pauses to allow you to interrupt Model 204 or to cancel the current request if too much output is being received. The CICS interface indicates that it is in pause mode by displaying the question mark (?) prompt in the first five positions of the next line on the terminal.
Valid user responses are:
-
Enter
C(cancel), followed by a carriage return. The current request or operation is canceled, and Model 204 is then ready to accept terminal input from the user. -
Enter a carriage return or any other character (except
C). The interface goes on to the next page.
Because the pause and cancel capability is activated at the end of a page, be sure not to set the OUTLPP (number of lines per page) parameter to zero unless you want suppressed pausing and production of a header on the new page. If OUTLPP=0, there is no logical end-of-page, and the interface never executes the pause.
The attention key facility is not available on Teletypes for the CICS interface. Pause mode is the only way to control requests that provide more output than desired.