Build Your Own Arcade Controls Forum
Arcade Collecting => Miscellaneous Arcade Talk => Topic started by: vanwatson on December 05, 2014, 11:23:25 pm
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What is the coin size battery used for in arcade games? it's for the settings and to keep
the EPROM chips turned on when the power is off.
The Battery goes to the watch dog circuit?
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It all depends upon the particular game machine in question.
Some modern (expensive) machines use desktop computers inside them so there could be two different sizes of coin cell batteries that might be used. This would depend also on the particular motherboard installed inside the computer.
Some machines (like Atari/Midway) use a couple of different size coin cell batteries on the game board for cmos settings.
Some older games use a soldered-in rechargeable 3.6 volt ni-cad battery (which leaks badly and corrodes the board). Really old Megatouch countertop games used a 3.6 volt "1/2 AA" Lithium cell with axial leads (not rechargeable) soldered to the board
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But what is the battery for? to power what? it is used for what purpose?
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But what is the battery for? to power what? it is used for what purpose?
to save the CMOS settings. like difficulty, game play cost, lives, etc
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But what is the battery for? to power what? it is used for what purpose?
Saving high scores, memory backup, programmable settings, etc.
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Saving high scores, memory backup, programmable settings, etc.
to save the CMOS settings. like difficulty, game play cost, lives, etc
Not all Arcade games use a battery? or NVram , so how did they save the high score, memory back up, cmos settings, level difficulty, game play cost , etc.
Mostly the Cmos setting was stored in a ROM chip but other games Cmos settings was stored in a NVRAM
What are the CMOS settings? it is the bios or something different
The Journey Arcade game will not boot up or start with no battery . I needs the batteries 5 volts to start the watchdog circuit, reset circuit, boot up
The watchdog has some kind of voltage sensing , maybe take a look at the schematic of Journey Arcade game in the early 80's to know why it needs the battery to boot up
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on your board should be a switch/and or jumper point to reset the board
this is called fourced reset >hard< not soft
remove batt and try it,if it dose not hard reset,chk the shockey diode for open or short
>common problem<
ed
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Is the shockey diode in the reset circuit?
What are some common reset circuits?
1.) 555 timer is a reset circuit
2.) Decoder is a reset circuit
3.) what other circuits can be a reset circuits in arcade games?
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yes it is right with either the switch or jumper >high side< not grounf side.,
555 is a 1 shot timer,which need's to be reset every xx depending on it's r/c constant.,and for wdt decorder chip's,gate's/nor/_or/exulsive or/nor/decade counter's,it run's the gamment,it all depend's on the board and complexity of the down stream circuit's and there demand's..,some may have different timming issuie's
or different _ce/_cw/clk/reset/_reset,and most of all there call in the micro proseser
"register stack",which by nature is rom controlled >game rom<.
so basicly as i have been trying to explain to u
when the wdt fire's u have a down stream problem,this is where u need to know what line's
should be doing at >xx< and what they are not to be doing,the wdt is a good starting point,as it will by it's control line's tell u where u need to be to repair the game board in question
ed
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So the Watch dog circuit ONLY detects/watches the logic stages of the control lines? not the address lines or data lines?
The watch dog circuit gets triggered/fired on only when the control lines are stuck high or low? not the address lines or data lines?
The Bios is on the control lines?
The Cmos settings is on the control lines?
The boot up is on the control lines?
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as a rule control line's olny
there is other circuit's that watch for data/address line's
ed
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Do you know why the watch dog circuit only watches the control lines only and not the address lines and data lines? why are the control lines so important
there is other circuit's that watch for data/address line's
What circuits are these called? are they watch dog circuits also?
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this may help u understand alot more clearer
ed
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Yes the watchdog timer circuits have a Watched time interval , if the control lines don't have data during the watched time interval the watch dog timer will pulse a time out signal to the Reset circuit
The Watched time interval is either in milliseconds or microseconds
The Control line data must be toggling logic high low signals constantly?
If the control line data is stuck low or stuck high , the watchdog timer circuit will pulse a time out signal that is sent to the Reset circuit
The Reset circuit is mostly a 555 timer, Pin#2 is the trigger input on a 555 timer
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now that u have the theroy,u should understand u can and should diable the wdt well
servicing the board in question,with that said today's game set board's
as a rule do not use a single 555 but rather a gpi take's over the roll
like the golden tee golf green or red board the wdt is truly in a pga style chip
it's name is house keeper,no word of lie on that name,i even took a double take
when i read it off on the schematic
ed
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,u should understand u can and should diable the wdt well
servicing the board in question,
When servicing troubleshooting a board:
1.) Ok I unsolder the watch dog circuit to disable it
2.) Do I jumper wire the reset pin to ground on the CPU to hard wire a reset to ground while I'm troubleshooting the board?
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the wdt is controlling olny 1 line to the cpu
so there is where u would bisable it >open it<,
and yes i use a switch from reset to ground >momtery<
so when i want a hard reset i just push and count to 3 or 5
ed
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Ok thanks for the help