Radio Shack TRS-80 Model II Reference Manual page 210

Model II TRSDOS
PRLINE
Print Line (function code 19)
This routine sends a line to the Printer. The line can include control characters as
well as printable data. See
PRCHAR
for a list of intercepted codes.
See
PRCHAR
for addition notes on serial output and on special character handling.
Entry Conditions
(HL)
=
Start of text buffer containing data and controls to send to Printer
B
=
Length of buffer (number of characters to send)
C
=
Control Character (any character) to send after last character in
buffer
A
=
19
Exit Conditions
NZ
=
Error
A
=
Error Code
PRCTRL
Control Printer Operations (function code 95)
This routine lets you select various printer options and check the status of
printer-related functions.
Note: If you are using the spooler's capture function, the captured data is sent
directly to the capture-file-regardless of what control settings are selected. If you
are using the spooler's print function, the printed data will be interpreted according
to the currently selected control settings. See
SPOOL
for details.
Entry Conditions
A =95
C
=
Used with certain options (see option list below)
B
=
Option code:
246