RECALL LINE utility RP AUTOMATION INC. DEC 1988

Preliminary Documentation

1.0 Introduction

The programs contained in this file are used to enable a feature

whereby the last lines that have been typed into the system can

be recalled back onto the CRT screen, and re-entered again as the

same or different commands. When this feature is enabled, typing

<CONTROL>-B will cause the previously typed line to appear on the

screen.

2.0 Subroutine Description

The following subroutines are provided in this package:

Name Description

rp..recall.line This program is EXECUTE'd to obtain the

feature of having a <CONTROL-B> keypress

cause the last line typed to reappear on

the screen. This line can be edited or

used without change by typing <RETURN>.

Less recent lines can be recalled by

multiple <CONTROL-B> keypresses.

rp..add.arg These programs are used in order to

rp..check.br provide the RECALL LINE function,

rp..check.hw.addr but they should not be EXECUTE'd by

rp..check.instr.type the user.

rp..decode.data

rp..get.dest

rp..get.numb4

rp..get.source

3.0 Software Installation

The software is installed using the following procedure:

1) Use the ZALLOCATE command to get the data area necessary

for this function to execute. This is done by typing:

ZALLOCATE n

where 'n' is an integer between 1 and 12, inclusive.

2) LOAD the file RP._RECALL.LINE by typing:

LOAD RP._RECALL.LINE

4.0 Software Execution

1) Execute the RP..RECALL.LINE program by typing:

EXECUTE RP..RECALL.LINE

Executing this program will cause the VAL II system to

react every time a <CONTROL>-B is seen from the keyboard.

The last line that had been typed will automatically get

re-entered as if it was re-typed on the keyboard. This

combination of keys is accomplished by holding down the

<CONTROL> key, while at the same time typing the 'B' key.

2) Subsequent <CONTROL>-B keypresses will result in lines

that were previously typed. At some point, the buffer

that contains all of the typed data will wrap around and

the data will start to repeat.

5.0 Other considerations

1) This feature is invoked as soon as the program completes

and tells the user that it is active. Since this program

make use of the ZALLOCATE'd area in VAL, no other program

which uses this area can be running at the same time. If

this warning is not heeded, then FATAL CPU ERRORs can occur.

2) If the system is shut down, and then restarted, the RECALL

LINE feature does not automatically get restarted. The

RP..RECALL.LINE program needs to be EXECUTE'd again to

restart this feature.

6.0 Variable names used

The following list of real variable names are used within this

set of programs:

rp..beg.addr rp..br.ind rp..br.save[]

rp..changed[] rp..chg.ind rp..data.zpoke[]

rp..flag rp..i rp..instr

rp..instr.parms rp..instr.type rp..instr1

rp..instr2 rp..instr3 rp..instr4

rp..instr5 rp..instr6 rp..instr7

rp..instr8 rp..orig.zi rp..rec.int[]

rp..rec.int.addr rp..z.i