CHANGE.FILE V01 RP AUTOMATION INC 11JAN89

DESCRIPTION

The programs in this file allow changes to be made to files on

a floppy diskette.

The file to be changed could be either an ASCII file (regular

VAL file containing .PROGRAM's, .LOCATIONS, and .REALS), or a

binary file (CALIBRATION OVERLAY, POTCAL, or diagnostic file).

PREPARATION

Load the CHANGE.FILE file into memory.

PROGRAM EXECUTION

After the "change.file" program has been executed, the normal

steps that this program follows are:

1. Wait for correct diskette to be in disk drive

before continuing. Press <ENTER> when diskette

is ready.

2. Ask for the name of the file to be changed. If

no name is entered, then the program ends.

3. Ask whether this is an ASCII file, or a BINARY

file. All files that get LOAD'd into a VAL-II

system are ASCII files. Any files that need

a different method (OVE or DIAG) are BINARY

files.

4. Ask for name of the file to be created. This

file will contain all of the changes. Again,

it is possible to EXIT the program by entering

a NULL name (just press the <ENTER> key).

5. The two files are then opened on the diskette

and reading and writing commences.

6. Each block of data that is read from the first

file is displayed on the CRT screen (256 bytes

per block). The option is given to make any

changes to that block of data. The new data is

then written out to the diskette as a block of

data for the new file. This process continues

until the entire file has been read, modified,

and written.

PROGRAM EXECUTION (continued)

7. When the file is finished, the program PROMPTs

for another filename to be changed. This will

continue until all files to be changed have

been done. The program will EXIT when no name

is given as the response to the filename query.

NOTES

Because of the way that the data is read from the diskette (in

blocks of 256 bytes), it is likely that parts of one line will

be in one block, while the rest of that line will be in the

next block.

When changing the data, make sure that the address is an even

octal number. Also, make sure that both bytes are entered as

the data that is to be changed. This is because everything in

this system works on 16-bit values and this data is only 8-bit

values.

MESSAGES

*** Floppy error nn ***

If a floppy error occurs during the program, then this message

will get displayed, where 'nn' is a number which corresponds to

the internal floppy disk drive error code. The codes are:

2 = File already exists (creating new file with same name)

3 = File does not exist (opening file for reading)

4 = Communications error between VAL & floppy

5 = Disk full (writing to disk)

6 = Communications error between VAL & floppy

7 = Communications error between VAL & floppy

10 = Communications error between VAL & floppy

11 = Communications error between VAL & floppy

12 = Floppy not ready

13 = Floppy read error (diskette may be bad)

14 = Communications error between VAL & floppy

41 = No STX received during block transfer

42 = Incorrect checksum received during block transfer

*** ILLEGAL ADDRESS ***

If an incorrect value is entered for the address to change data

at, then this message will get displayed.

*** ILLEGAL 16-bit octal number ***

If an incorrect value is entered for an octal number, then this

message will get displayed.

*** All Done ***

When program has finished this message gets displayed.