Counter for an old Chinese game GO

Presented device is an useful counter for players of an old Chinese game GO. To make the counter more universal, a possibility to set any time of the game and the movement of the player. This allows you to use the device while playing on a smaller board (13x13) and Atari GO. The device can be used for other games such as chess. It has three different systems of counting, which are described below.

Electronic system:
Main element of the electronic system is microcontroller Atmega8515. Because of a large number of IO ports, this type of AVR microprocessor is suitable for this system.
This microcontroller controls two four-digits LED displays, supports 7 buttons and a buzzer. PA and PB separately support cathodes of the diodes on the displays, while all anodes of both displays are connected in parallel and plugged sequentially by emitter repeaters to PC0-3. Colons of the displays are controlled by PC4-5. Both displays are separately multiplex controlled.
PA works in configuration of input pulled up to VCC and supports six buttons. Additionally, one of those buttons shorts the RESET pin to the mass through the capacitor. While normal operation, transistor Q5 pulls up the RESET pin to VCC. This solution allows you to use function POWER DOWN of the microprocessor to switch off the device. Pressing S7 wakes up the microprocessor and starts normal operation.
In addition, the end of turn buttons have external exits. 3,5 jack sockets (in the counter with prominent displays) and 2,5 jack (the counter with smoky glass panes) allow you to connect external large and strong buttons for each player.
Buzzer was based on hardware counter. Emitting MIDI sound is made by writing the data into OC1A and OC1B registers (frequency), and zeroing them (length of sound lasting). Both registers were engaged because of hardware reset of the counter TCNT1.
The device is powered by four accumulators R3. The system consumes from 40mA to 160mA, depending on the brightness of displays, which is adjustable using buttons.
Another device with smoky glass pane is powered by three accumulators, the system was simplified.

How it works:
After starting, the system is ready to start the game (the time of game is set to 30 minutes, while the time of byo-yomi is set to 30 seconds). Buttons S4, S6 are used to brighten and darken the displays. Pressing S3, S5 causes changing the moode of conversion, in turn:

• minutes of basic time – player #1
• seconds of basic time – player #1
• minutes of basic time – player #2
• seconds of basic time – player #2
• time of byo-yomi – player #1
• time of byo-yomi – player #2
• number of allowed mistakes – player #1
• number of allowed mistakes – player #2 (number of allowed exceedings of the movement time)
• game mode (1 – game with basic time with limited time of turn, 2 – game with basic time from 00:00, then byo-yomi is started, 3 – game only with byo-yomi time)

You can go into game from zero mode by pressing the central button S7. Then the game is paused, the following pressing activates it, then pauses etc. Each player has their own button: S1 and S2. Moreover, you can connect the external ones to mini-jack sockets. Pressing S1 and S2 finish the movement, then byo-yomi time is written off and the remaining time of the game displayed. Remaining 5, 4, 3, 2, 1 seconds are indicated by beeping with an increasing tone to beep constantly when byo-yomi reaches 0 seconds. Byo-yomi time can not be greater than the remaining time of the game. When the remaining time of the game is less than the initial set value of byo-yomi, it decreases with each new turn to zero second.
In the first mode, by pressing buttons S3 or S5, players can check the remaining time of the opponent, and when it is equal to zero or only the game with byo-yomi is active, players have a preview of the number of possible mistakes that the opponent can do. After crossing the range of possible mistakes, the game is ended with a short squeal and displaying inscription FAIL on the display of the loser player.
On and off are accompanied by various three-tone sounds, delicate treble three-tone squeaks are heard when the buttons are used.

Housing:
It was to be the smallest possible. Two planks and laminates in the trapezoidal shape painted on the sides were used. The prominent displays do not look very well, so another version of the device as made.

Pictures:



Schemes (two first pictures are schemes of the first version of the device, the following – the second version):




Link to original thread (useful attachment) – Licznik do starochińskiej gry GO