GB2095451A

GB2095451A - Control circuitry for a gaming machine

Info

Publication number: GB2095451A
Application number: GB8208295A
Authority: GB
Original assignee: PANELWIRE CONTROLS Ltd
Current assignee: PANELWIRE CONTROLS Ltd
Priority date: 1981-03-21
Filing date: 1982-03-22
Publication date: 1982-09-29
Also published as: GB2095451B

Abstract

Control circuitry for a gaming machine includes a plurality of lights for indicating play functions and other facilities connected to electrical supply wires which are arranged in a multi- plexing system. A switch in each wire is controlled by the presence of a pulse in the wire and is read at a predetermined time with respect to the edge of a pulse to avoid pulses of induced current. A central processing unit controls the multiplexing and the reading function.

Description

SPECIFICATION Improvements in or relating to control circuitry for gaming machines This invention is concerned with improvements in or relating to control circuitry for gaming machines i.e.

machines for playing games of chance. One commonly known type of gaming machine is a fruit machine.

According to the present invention there is provided control circuitry for a gaming machine, said circuitry including a plurality of indicators with electrical supply lines arranged in a multiplexing system, means responsive to the presence of current pulses in each of the supply lines, and a central processing unit for controlling the reading of the current responsive means in the respective supply lines only at predetermined times, during pulse periods so as to avoid being responsive to pulses of induced current.

Preferably there is provided a pair of synchronized central processing units arranged to control between them three functions comprising the multiplexing, the reading of the current responsive means in the respective supply lines only at predetermined times during pulse periods so as to avoid being responsive to pulses of induced current, and the game programme, the central processing units sharing peripheral equipment of the control circuitry.

Advantageously, a first of the central processing units controls the multiplexing and the reading of the current responsive means, and the second of the units controls the game programme.

An embodiment of the present invention will now be described by way of example only.

In a fruit machine, there are generally provided a considerble number of lights which may have different functions in the machine. For example, certain of the lights when lit may indicate play functions which are available to the player, others are used to illustrate, when lit, the result of a gamble which may have been taken by the player, or the achieving of a winning combination of symbols, while others may be provided simply for decorative effect. It is extremely convenient, because of the number of lights involved, to connect the lights to electrical supply lines or wires which are arranged in a multiplexing system, whereby the number of wires necessary to control the switching of the indicators can be considerably reduce.In a multiplexing system, however, the wires are located so close to one another that when a current is passed through one wire there tends to be a current induced in an adjacent wire, and this of course causes problems when it is desird to know what wires are live at any one time.

This problem is avoided by arranging for a switch controlled by the presence of a pulse in each wire to be read at a pedetermined time during the period of a current pulse in the wire, preferably just prior to the trailing edge of the pulse. In this way any induced current pulse will have died away prior to the switch being read and therefore a pulse will be sensed in only a line to which it has been applied.

The control circuitry of the machine normally includes a central processing unit (CPU) for controlling the lights and also the game programme of the machine. However, when a multiplexing system is used, with a switch reading as described above, it may be desired to reduce the work which the CPU has to do in the time provided, when it also has the game programme to control. The use of a separate integrated circuit for the multiplexing system has been considered but is not feasible, because there would be no synchronism between the integrated cicuit and the CPU and such synchronism is required when the reading function is such as described above.

In a modified circuitry, there can therefore be provided a second CPU which is arranged to control the multiplexing and the reading function, thus enabling the first mentioned CPU to control the game programme. The CPUs are synchronized and can use the same peripheral equipment of the control circuitry on a time sharing basis as such peripheral equipment is not continuously in use.

There is thus provided control circuitry which provides a simple and effective arrangement for making use of multiplexing. The arrangement provided is further useful in that the CPUs are capable of carrying out the desired functions, but also have the facilities for carrying out additional functions if so desired Various modifications may be made without departing from the invention. For example it will be appreciated that the specific functions described above can be carried out by the CPUs in different combinations, such as one CPU controlling the multiplexing and the game programme and the other controlling the reading function. It will also be appreciated that the control circuitry may be utilised in gaming machines other than fruit machines and indeed may be used in other applications.

1. Control circuitry for a gaming machine, said circuitry including a plurality of indicators with electrical supply lines arranged in a multiplexing system, means responsive to the presence of current pulses in each of the supply lines, and at least one central processing unit for controlling the reading of the current responsive means in the respective supply lines only at predetermined times, during pulse periods so as to avoid being responsive to pulses of induced current.

2. Control circuitry according to claim 1,wherein there is provided a pair of synchronized central processing units arranged to control between them three functions comprising the multiplexing, the reading of the current responsive means in the respective supply lines only a predetermined times during pulse periods so as to avoid being responsive to pulses of induced current, and the game programme, the central processing units sharing peripheral equipment of the control circuitry.

3. Control circuitry according to claim 2, wherein a first of the central processing units controls the multiplexing and the reading of the current respon

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Improvements in or relating to control circuitry for gaming machines This invention is concerned with improvements in or relating to control circuitry for gaming machines i.e. machines for playing games of chance. One commonly known type of gaming machine is a fruit machine. According to the present invention there is provided control circuitry for a gaming machine, said circuitry including a plurality of indicators with electrical supply lines arranged in a multiplexing system, means responsive to the presence of current pulses in each of the supply lines, and a central processing unit for controlling the reading of the current responsive means in the respective supply lines only at predetermined times, during pulse periods so as to avoid being responsive to pulses of induced current. Preferably there is provided a pair of synchronized central processing units arranged to control between them three functions comprising the multiplexing, the reading of the current responsive means in the respective supply lines only at predetermined times during pulse periods so as to avoid being responsive to pulses of induced current, and the game programme, the central processing units sharing peripheral equipment of the control circuitry. Advantageously, a first of the central processing units controls the multiplexing and the reading of the current responsive means, and the second of the units controls the game programme. An embodiment of the present invention will now be described by way of example only. In a fruit machine, there are generally provided a considerble number of lights which may have different functions in the machine. For example, certain of the lights when lit may indicate play functions which are available to the player, others are used to illustrate, when lit, the result of a gamble which may have been taken by the player, or the achieving of a winning combination of symbols, while others may be provided simply for decorative effect. It is extremely convenient, because of the number of lights involved, to connect the lights to electrical supply lines or wires which are arranged in a multiplexing system, whereby the number of wires necessary to control the switching of the indicators can be considerably reduce.In a multiplexing system, however, the wires are located so close to one another that when a current is passed through one wire there tends to be a current induced in an adjacent wire, and this of course causes problems when it is desird to know what wires are live at any one time. This problem is avoided by arranging for a switch controlled by the presence of a pulse in each wire to be read at a pedetermined time during the period of a current pulse in the wire, preferably just prior to the trailing edge of the pulse. In this way any induced current pulse will have died away prior to the switch being read and therefore a pulse will be sensed in only a line to which it has been applied. The control circuitry of the machine normally includes a central processing unit (CPU) for controlling the lights and also the game programme of the machine. However, when a multiplexing system is used, with a switch reading as described above, it may be desired to reduce the work which the CPU has to do in the time provided, when it also has the game programme to control. The use of a separate integrated circuit for the multiplexing system has been considered but is not feasible, because there would be no synchronism between the integrated cicuit and the CPU and such synchronism is required when the reading function is such as described above. In a modified circuitry, there can therefore be provided a second CPU which is arranged to control the multiplexing and the reading function, thus enabling the first mentioned CPU to control the game programme. The CPUs are synchronized and can use the same peripheral equipment of the control circuitry on a time sharing basis as such peripheral equipment is not continuously in use. There is thus provided control circuitry which provides a simple and effective arrangement for making use of multiplexing. The arrangement provided is further useful in that the CPUs are capable of carrying out the desired functions, but also have the facilities for carrying out additional functions if so desired Various modifications may be made without departing from the invention. For example it will be appreciated that the specific functions described above can be carried out by the CPUs in different combinations, such as one CPU controlling the multiplexing and the game programme and the other controlling the reading function. It will also be appreciated that the control circuitry may be utilised in gaming machines other than fruit machines and indeed may be used in other applications. CLAIMS

3. Control circuitry according to claim 2, wherein a first of the central processing units controls the multiplexing and the reading of the current respon sive means, and the second of the units controls the game programme.

4. Control circuitry according to any of the preceding claims, wherein each of the current responsive means comprises a switch the condition of which is read immediately prior to the trailing edge of a current pulse.

5. Control circuitry for a gaming machine substantially as hereinbefore described.

6. A gaming machine having control circuitry according to any of the preceding claims.