Commodore CBM - Secondary Address Codes

Table 4-2. Secondary Address Codes
Seeondary
Operation
Address Code
o(default)
Open for read
PET Tape
1
Open for
write
Cassette
2 Open for write and end-of-
Units
tape mark
(EOT) when file is closed
o(default)
Normal
print
1
Print under Format statement
control
2
Transfer data fram PET
to
PET Line
Format statement
Printer
3
Set variable lines per page
4
Use expanded diagnostic
messages
5
Byte data for programmable
character
PET IEEE o(default)
No secondary address code
488
sent
Deviees 1 through 31 Refer to device manual
File Names
The filename parameter in the OPEN statement specifies a program or data
file by name. If the
OPEN is for a write. this is the name that will be assigned to the
file being created. If the
OPEN is for a read. this is the name that was written when
the program was created.
For cassette 1/0. the filename parameter is optional. If omitted. the PET
defaults the file na me to a null string .... ; the null string will match the first file
name encountered on the tape. For other devices the file name may or may not be
optional. depending on the requirements of the device. Note that the logical file
nûmber
is separate and distinct from the file name. The logical file number (first
parameter in the
OPEN statement) is for internai PET use; the file name. for tape
cassettes.
is the name written in the tape header to identify a program or data fi le
stored on tape.
OPEN may be executed in immediate or program mode.
141