Printer Interfacing - AMSTRAD CPC464 User Manual

A special function is available to inspect the joysticks directly. This is JOY(0), for the first joystick,
and JOY(1) for the second. The function returns a bit-significant result which indicates the state of
the joystick switches at the last keyboard scan. As there are 50 keyboard scans per second the result
is virtually the instantaneous state of the joystick switches.
The joysticks return values as follows where KEY is the value to use in an INKEY function and
MIRROR is the equivalent keyboard key:
First Joystick JOY(O)
Up Bit 0
Down Bit 1
Left Bit 2
Right Bit 3
Fire 2 Bit 4
Fire 1 Bit 5
Note that when the second joystick is interrogated the CPC464 cannot tell the difference between
the joystick and the indicated keyboard keys. In practice it is most unlikely that a conflict of
interpretation will exist. Indeed the keyboard could be used as a substitute for the second joystick.
When using the AMSOFT JY1, the second joystick is identical to the first, and plugs into the socket
on the side of the first joystick. No special wiring is required to allow use of the second joystick.
The 9 pin socket marked
personal computers, athough these do not allow a second joystick to be fitted unless a special adaptor
is used. However, you should not attempt to use one of these joysticks as a second joystick to be
plugged into the side of the AMSOFT JY1 joystick.
Software writers may consider providing an option at the start of their programs to enable the user
to select either joystick operation or cursor key operation (Where the [COPY] key or some other
nominated key could be used as a fire button).

7.2 Printer interfacing

The AMSTRAD CPC464 allows the connection and use of an industry standard ' CENTRONICS' style
interface printer.
The printer cable is simply constructed as a one-to-one connection between the
parallel printer connector. Note that there are two less ' fingers' on the computer' s printed circuit
board than on the printer connector; permitting use of a standard printed circuit board edge
connector.
The actual interface details are illustrated in Appendix V.
KEY Second Joystick
72 Up
73 Down
74 Left
75 Right
76 Fire 2
77 Fire 1
USER PORTS (I/O)
will accept standard joysticks that work with other
JOY(1) KEY MIRROR
Bit 0 48 6
Bit 1 49 5
Bit 2 50 R
Bit 3 51 T
Bit 4 52 G
Bit 5 53 F
PRINTER
port and