Envoy ACP/XF Application Programming Manual

Normal Response Mode (NRM) Protocols

EnvoyACP/XF Application Programming Manual–132179

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Pseudocode Examples

The examples in this subsection show the basic logic behind initializing a NRM link.

These are not actual code examples.

SDLC Point-to-Point Primary Station

This example shows how to initiate an SDLC link for a point-to-point primary station

that performs two-way alternate communication over half-duplex, nonswitched line

facilities.

In this example, the line name is $SDLC0.

!Open the line "SDLC0"

OPEN SDLC0,%36

If <> do error handling

!When using nonextended control mode

!you can open the line for exclusive read or write access and

!for nowait I/O with a maximum of 14 concurrent outstanding

!requests.

!The flags parameter %36 specifies all of those characteristics.

!The OPEN procedure assigns a unique line number to this

!particular opening of the line $SDLC0 and returns it to the

!application process by way of the line^fnum integer variable

!Get the current line setting.

SETMODE fnum,16,,,current_value !two words

If <> do error handling

!Set the line to point-to-point primary,

!half-duplex,nonswitched

!REJ supervisory frames not allowed

!RS-232C line interface

SETMODE fnum,16,%4

If <> do error handling

!Send SNRM

CONTROL fnum,13,0

If <> do error handling

AWAITIO fnum

If <> do error handling

If the point-to-point primary station is to perform two-way, simultaneous

communication over full-duplex, nonswitched line facilities, use the preceding sequence,

but modify the parameters in the SETMODE call as follows:

SETMODE fnum,16,%414