User manual

Page 20
Document No. 80-15151 Issue 6 HEBER LTD
6 MACHINE OPERATION
This section discusses how various standard amusement machine functions can be implemented.
6.1 Driving Reels
Up to six 12V Stepper Motor Reel Mechanisms may be connected to the “REEL” connector, P7. +12V
outputs are available for the motor common connection and GND/Vcc are available for the Opto
supply. A 6*6 subset of the Lamp Multiplex is configured so up to 6 lamps per reel may be
accommodated, in either “sinking” or “sourcing” mode (depending on the wiring of the Reel
Mechanism. 6 inputs, IP0-5, are provided for the Opto Inputs
When driving stepper motor reels, because the maximum (static) current load of each winding is
400mA (assuming 30Ω, 12V windings), it is important to connect the motors to distribute the load
evenly amongst the TPIC6259 driver chips.
The recommended method of connection is to wire the reel motors as follows:
Table 15. Recommended Reel Stepper Motor Drive Connections
REEL 1 OP0-3
REEL 2 OP4-7
REEL 3 OP8-11
REEL 4 OP12-15
REEL 5 OP16-19
REEL 6 OP20-23
This guarantees that a maximum of 3 motor windings are driven simultaneously by any one TPIC6259
device which is within the ratings of the device even under the worst case of a reel being stationary
and unchopped. Of course, when the motor is running or is being chopped the average current drops
significantly.
Extra reels could be connected via pins on the other connectors. Providing the software chops the
current to the reels when they are not spinning, an extra 2 reels can be wired to OP24-27 and
OP28-31 and should allow the TPIC6259s to remain within their ratings.
NB: The +12V outputs on P7 Pins 45-50 are fed directly from the +12V Input to the Pluto 5 Board on
P3, Pin 4. It does not go via Fuse F1 on the board.
6.2 Reading the DIL Switches
The state of the DIL Switches may be read at any time by reading the memory locations as described
in Section 5.12.
6.3 Reading the Switch Inputs
The 32 switch inputs may be read at any time by reading the memory locations as described in
Section 5.11 above.
In most applications, these inputs should be debounced in software. A typical debounce algorithm
might be to read the switches every 1mS, but only register a change of state on the input after it has
been stable for 3 consecutive readings.
It is possible to implement, say, a 256 multiplexed switch input array by using, 8 of the Open Drain
Outputs OP0-63 as strobes and 8 of the Inputs IP0-31. In this case, a diode would need to be
connected in series with each switch.