Device-dependent output information

Using certain options for outputting information can make the application program device-dependent. Some options allow the application program to control certain features of devices receiving output. Descriptions of the effects of various output options follow.

System Control Area (SCA)

An option of the MFS Language utility allows the creation of an SCA field in the first segment of a message or, if LPAGEs are defined, in the first segment of any or all LPAGEs. This field allows application program control of specific device features when the features apply to the device for which the message is destined. The first 2 bytes of the SCA field are defined as shown in these tables:

Usage notes follow both tables.

Table 1. Valid bytes and bits for TYPE=3270, SLU 2, DPM-An, or DPM-Bn
Byte	Bit	Description
0	0-7	Should be 0.
1	0	Should be 1.
	1	Force format write (erase device buffer and write all required data).
	2	Erase unprotected fields before write.
	3	Sound device alarm.
	4	Copy output to candidate printer.
	5	B'0'—For 3270, protect the screen when output is sent. For DPM, demand paging can be performed.
		B'1'—For 3270, do not protect the screen when output is sent. For DPM-B, autopaging can be performed.
	6	For the partition formatted 3290: B'0'—do not erase existing partitions. B'1'—erase all partitions before sending message. For others, should be 0.
	7	Should be 0.
Notes: For the 3290 in partition format mode, the DOF on the current message is checked to see if it is the same DOF used last. If it is, bit 6 in the SCA and DSCA operands is checked for the erase/do not erase partitions option before the output message is sent. The default for bit 6 is B'0', do not erase. If this bit is not specified, the output is sent according to the partition paging option specified, and partitions that do not receive output remain unchanged. If bit 6 is set to B'1', then existing partitions will be erased and the output is sent according to the partition paging option specified. The SCA bit settings are OR'd to the DSCA bit settings. For example, if byte 1 bit 5 in the DSCA for DPM-B is set to B'0' in the DSCA for DPM-B, the application program can request autopaged output by setting the SCA value to B'1'. (This request is honored only if present in the first segment of the first LPAGE of the output message.) SCA information is sent to the remote program or ISC subsystem in a DFLD identified by the parameter SCA. Any invalid bits for the device type are reset. The valid bits are used.

Table 2. Valid bytes and bits for TYPE=FIDS, FIDS3, FIDS4, FIDS7, FIJP, FIPB, or FIFP
Byte	Bit	Description
0	0-7	Should be 0.
1	0	Should be 1.
	1-2	Not applicable for FIN output devices.
	3	Set device alarm in output message header.
	4	Not applicable for FIN output devices.
	5-7	Should be 0.
Notes: Bits 1, 2, and 4 function only for 3270 and are not applicable to finance workstations. If set on by the program, and the message is edited for a finance workstation, they are ignored. For TYPE=SCS1, or SCS2, the SCA parameter is ignored. For TYPE=3270P, all bits except set device alarm are ignored.

Cursor location

An application program can set the cursor location on the screen either by setting a cursor attribute for a field or by using a special cursor positioning field in the output message.

Recommendation: Use the cursor attribute method because the application program does not need to know the position of fields on a device.

Using an option of the MFS Language utility, you can define a field in an output segment to allow the application program to request cursor positioning to a specific line and column on the device. Depending on the device output format used, there can be one or more such fields per LPAGE. If the field contains an invalid number it is ignored and the cursor is positioned as requested in the device output format.

The cursor field should contain two 2-byte binary numbers (no alignment required), the first containing the line number, the second containing the column number. The minimum value for the line or column is 1. For 3270-An device types, the maximum value for the line is the first parameter of the SIZE= operand; the maximum value for the column is the second parameter of the SIZE= operand. The following table lists the valid line and column values.

Table 3. Maximum line and column values for MFS device types
	Maximum Value
MFS Device Type	Line	Column
FIDS (240 characters)	6	40
FIDS3 (480 characters)	12	40
FIDS4 (1024 characters)	16	64
FIDS7 (1920 characters)	24	80
3270,1 (480 characters)	12	40
3270,2 (1920 characters)	24	80
3270-An
SIZE=(12,40) (480 characters)	12	40
SIZE=(12,80) (960 characters)	12	80
SIZE=(24,80) (1920 characters)	24	80
SIZE=(32,80) (2560 characters)	32	80
SIZE=(43,80) (3440 characters)	43	80
SIZE=(27,132) (3564 characters)	27	132
SIZE=(62,160) (9920 characters)	62	160