Writing Data Onto Clipped (Protected) Cards; Reading Data From Cards - HP 82104A Owner's Handbook Manual

Card Reader Operations 23
You can terminate any data read or write session at any time by pressing
or ( = 3 -
Using (wota). The (write data) function is a simplified version of
(wotax]. You have little control over the registers written using (wbTa).
When is executed, the calculator prompts for cards until all of the
data registers in the calculator have been written to cards, or until you
terminate the write session.
begins writing with data storage register Ry,.
Labeling Data Cards. It is a good idea to label your data cards so that
you don't lose track of the information. Write **DATA"' on the card, and
if the data 1s associated with a specific program, write the program name
as well as the version number or date.
Writing Data Onto Clipped (Protected) Cards
After a data card has been written using or (WDTA], you can
protect the information by clipping the corner off of the card (refer to
page 10).
In the event that you decide to use the protected card again, you can
simply set the Overwrite Flag (flag 14), execute or (wota), and
insert the card.
Attempting to write on a protected track (one with the corner clipped) will
result in a special message:
PROTECTED
The card will pass through the card reader and is not written. The display
will prompt for another card with DY kk OF nn.
Flag 14 is automatically cleared each time you turn the HP-41C on and
when any read or write operation is completed or terminated.
Reading Data From Cards
There are two data reading functions that are similar to the write func-
tions: (read data as directed by X) and (read data). In
addition, there is a third procedure used to read data cards without using
either or (RDTAJ.