Acorn Computers Limited PLUS 1, User Manual

Page: 10 / 30

4 Setting up
one way up. Turn the Electron on again and the joysticks or games paddles are now ready for
use with suitable games or can be read from BASIC — see chapter 3 for further details.
Using cartridges
To use a cartridge produced by Acorn for the Plus 1, you must first plug it into either of the two
shuttered slots in the top of the Plus 1. Insert the cartridge with its label towards you (ie facing
the keyboard), pushing it into the slot so that the right-hand end makes contact first, then
pressing it home until you hear it click into place. The cartridges are designed so that it is very
difficult to insert them the wrong way round.
With a cartridge inserted correctly, either press
BREAK
(if the Electron was turned on) or
turn the Electron on. Instructions in the use of the cartridges vary; full details will be supplied
with any cartridge you purchase.
Using tape cassettes with the Plus 1
Whenever you use
LOAD, SAVE, CHAIN, *LOAD, *RUN
or *
EXEC,
the Plus 1 printer port and
analogue interface are automatically disabled for the duration of that command. If you are
using the
BPUT#, BGET#, INPUT#
or
PRINT#
commands in a program, you should use the *
F
X163,128,1
command to explicitly disable the printer port and analogue interface before using
the tape, and re-enable them afterwards using *
F X163,128,0.
Disconnecting the Plus 1
If you should need to disconnect the Plus 1 for any reason, be careful to turn off the Electron
first, then reverse the sequence of actions used to attach it. Note that the Plus 1 should not be
disconnected and reconnected repeatedly, as this will cause wear of the expansion connector
contacts.