DOS 3.3 6502 Editor Assembler: PR slot command

There is a .PR# slot# command in the DOS 3.3 6502 editor assembler of the DOS tool kit. If you use this command you get not a file listing, but a dump of the buffer that starts with data entered by the user or LOADed from a text file.

After this part of the buffer has been printed, the dump continues with the garbage in the buffer beyond the last intelligible character to the end of the allowable buffer. This produces numerous @ signs or other characters depending on the contents of buffer memory after power-up and is a normal part of a Print or List of the assembly program to a printer using .PR# slot# from the editor.
Try it yourself.

1. Boot the DOS 3.3 6502 editor/assembler
2. LOAD a large source code file
3. List it to see what it looks like
4. Type NEW to clear the buffer
5. LOAD a smaller source code file
6. Type .PR#1 to send the DOS command to activate the printer
7. Type L to list the buffer to the printer

Notice that the last part of the first file follows the last line of the second file. Also notice that such a listing does not match the screen output when using the List or Print commands but instead follows the input format.

To obtain a listing with the same format as displayed on the screen using Print or List commands you must append ',@' to the ASM command. This assembles the file without generating an OBJect code file (see page 56 of the editor/assembler manual). To speed this process when using an Imagewriter and Super Serial Card on an Apple II+ or Apple IIe, do the following.

1. Set the Imagewriter print style to ultracondensed (17cpi)
2. Set the baud rate of printer and card to 9600
3. Send the output of the assembly to the printer using PR#

Notice that there is no period (.) preceeding the PR# command in this case. This is because you are not using the DOS command version but rather the editor/assembler PR# command. See the editor/assembler manual for the format of the PR# command on page 60 and a discussion on pages 60 and 61.

With an Imagewriter at 9600 baud, the above three steps reduce the listing time by 41% when comparing the default type style to the ultracondensed style.
Published Date: Feb 18, 2012