Hardware test program for Genesis Justifier, Menacer and\or ALG GAMEGUN?
- nintendo2600
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Hardware test program for Genesis Justifier, Menacer and\or ALG GAMEGUN?
Hello,
Does anyone here know of or have a test program to check the functionality of
Sega Genesis lightguns? I've looked around quickly on google but didn't
really find what I was looking for. Just something that can read what
is or isn't working on a lightgun be it the Menacer or Justifier flavor.
Specifically I'm going to be testing an American Laser Games GAMEGUN
which is both a Menacer and Justifier in one.
Thanks!
Does anyone here know of or have a test program to check the functionality of
Sega Genesis lightguns? I've looked around quickly on google but didn't
really find what I was looking for. Just something that can read what
is or isn't working on a lightgun be it the Menacer or Justifier flavor.
Specifically I'm going to be testing an American Laser Games GAMEGUN
which is both a Menacer and Justifier in one.
Thanks!
Re: Hardware test program for Genesis Justifier, Menacer and\or ALG GAMEGUN?
I couldn't trivially find any useful documentation about how the Justifier and Menacer worked, so had to look at BizHawk's source, where they say:
Menacer:
Down on normal pad ↔ back trigger (patent calls this "SW3")
Right on normal pad ↔ pause button (lower front trigger; "SW1")
Up? or Left? button on normal pad ↔ upper front trigger ("SW2")
Left? or Up? button on normal pad ↔ center front trigger ("SW4")
TH input ↔ low during instant Light
Usually uses hardware inside Genesis capture falling edge of TH to convert to coordinates
The 6-in-1 pack-in game has a calibration screen you could use for this.
Justifier:
Down button on normal pad ↔ trigger
Right on normal pad ↔ start button (side)
TH input ↔ becomes low when light
TR used as output to select between two guns
Not really clear why they're incompatible.
Menacer:
Down on normal pad ↔ back trigger (patent calls this "SW3")
Right on normal pad ↔ pause button (lower front trigger; "SW1")
Up? or Left? button on normal pad ↔ upper front trigger ("SW2")
Left? or Up? button on normal pad ↔ center front trigger ("SW4")
TH input ↔ low during instant Light
Usually uses hardware inside Genesis capture falling edge of TH to convert to coordinates
The 6-in-1 pack-in game has a calibration screen you could use for this.
Justifier:
Down button on normal pad ↔ trigger
Right on normal pad ↔ start button (side)
TH input ↔ becomes low when light
TR used as output to select between two guns
Not really clear why they're incompatible.
- nintendo2600
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Re: Hardware test program for Genesis Justifier, Menacer and\or ALG GAMEGUN?
I'm starting to think the gun itself is not working. Are you familiar with the ALG gamegun at all? I've opened it up
and I see a good amount of flux crust and possibly corrosion from the large resistor (or is this a color coded capasisitor?).
LE 1 and 2 only register the trigger in menu, neither game sees the sensor on screen or the start button. Menacer 6 in 1 doesn't register
the trigger or the start button and unless it moves the cursor on its own per chance, the photo diode isn't registering the aim on the screen
either. I'm using a CRT that I use for all my gun games and even cranked the brightness just to make sure it wasn't that and it
wasn't. I've checked the start button, trigger switch and the DB9 cord for continuity and they are each good. If I've attached pics of the PCB.
and I see a good amount of flux crust and possibly corrosion from the large resistor (or is this a color coded capasisitor?).
LE 1 and 2 only register the trigger in menu, neither game sees the sensor on screen or the start button. Menacer 6 in 1 doesn't register
the trigger or the start button and unless it moves the cursor on its own per chance, the photo diode isn't registering the aim on the screen
either. I'm using a CRT that I use for all my gun games and even cranked the brightness just to make sure it wasn't that and it
wasn't. I've checked the start button, trigger switch and the DB9 cord for continuity and they are each good. If I've attached pics of the PCB.
Re: Hardware test program for Genesis Justifier, Menacer and\or ALG GAMEGUN?
... I think I agree that that color of blue-green implies capacitor? But I'm really not confident.
There's nothing particularly complicated on that PCB. I think you're right that it's probably the phototransistor (metal can, letters "E" and "C" adjacent). What test tools, if any, do you have?
There's nothing particularly complicated on that PCB. I think you're right that it's probably the phototransistor (metal can, letters "E" and "C" adjacent). What test tools, if any, do you have?
- nintendo2600
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Re: Hardware test program for Genesis Justifier, Menacer and\or ALG GAMEGUN?
I have a digital multimeter but that is about it.
EDIT: The color code is Silver(grey?)\red\blue\green\Silver.
The photo transistor is a motorola MRD310 with the 3rd leg removed.
EDIT: The color code is Silver(grey?)\red\blue\green\Silver.
The photo transistor is a motorola MRD310 with the 3rd leg removed.
Last edited by nintendo2600 on Tue Mar 17, 2020 7:39 pm, edited 1 time in total.
Re: Hardware test program for Genesis Justifier, Menacer and\or ALG GAMEGUN?
Does your multimeter have a frequency test? If so, what does it say the frequency across the phototransistor is when you're pointing at a white screen?
- nintendo2600
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Re: Hardware test program for Genesis Justifier, Menacer and\or ALG GAMEGUN?
I'll have to check to see if it does. I've never used it to do something like that before but that is a pretty clever method of testing I have to say
- nintendo2600
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Re: Hardware test program for Genesis Justifier, Menacer and\or ALG GAMEGUN?
I hope there is some equal to the MRD310 if that does turn out to be the problem. I've googled it and digikey doesn't have them while amazon and ebay want at least $30 for 1! Some guy is selling a pack of 10 for $99. I'm so used to getting them 5 for a dollar with replacing the photo diodes\resistors on other systems like the Atari or Nintendo. I've not replaced one in one of these Sega Genesis guns like this before, never in this exact model for sure. I think I recall refurbing a Justifier years ago but I would have remembered if I paid out the wazzoo for the photo senor which I don't. That or I blocked it out on purpose
- nintendo2600
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Re: Hardware test program for Genesis Justifier, Menacer and\or ALG GAMEGUN?
I'll see about the test with the multimeter tomorrow and report my finding then. Thanks for your help in this matter.
Re: Hardware test program for Genesis Justifier, Menacer and\or ALG GAMEGUN?
MRD310 should be something you could replace with any phototransistor of comparable specs, i.e.
dark current around 5nA at room temperature - this is unusually low
3.5mA at 5mW/cm² 2870K blackbody
0.8mA at 0.5mw/cm² 940nm IR LED
2µs rise time
2.5µs fall time
Vishay's VEMT2500 series looks comparable - a little more IR centered (~830nm vs 800nm), although SMD.
dark current around 5nA at room temperature - this is unusually low
3.5mA at 5mW/cm² 2870K blackbody
0.8mA at 0.5mw/cm² 940nm IR LED
2µs rise time
2.5µs fall time
Vishay's VEMT2500 series looks comparable - a little more IR centered (~830nm vs 800nm), although SMD.
- nintendo2600
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Re: Hardware test program for Genesis Justifier, Menacer and\or ALG GAMEGUN?
I'd like to stay with a through hole if possible but I'm thankful to hear there is alternatives. Also, readinglidnariq wrote: ↑Tue Mar 17, 2020 8:03 pm MRD310 should be something you could replace with any phototransistor of comparable specs, i.e.
dark current around 5nA at room temperature - this is unusually low
3.5mA at 5mW/cm² 2870K blackbody
0.8mA at 0.5mw/cm² 940nm IR LED
2µs rise time
2.5µs fall time
Vishay's VEMT2500 series looks comparable - a little more IR centered (~830nm vs 800nm), although SMD.
this as a colored coded capacitor (I'm pretty sure it's a cap) it should be an 82 uF ±5% right? Just figuring
out what I'm gonna need just in case I repopulate the whole PCB as new.
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Re: Hardware test program for Genesis Justifier, Menacer and\or ALG GAMEGUN?
Usually green parts with such shape are inductors.
- nintendo2600
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Re: Hardware test program for Genesis Justifier, Menacer and\or ALG GAMEGUN?
Thanks for that info. Do you know where to buy them by chance? Ebay has nothing that matches.
The photo transistor is kinda interesting how it's set up. The emitter and collector are attached but the base isn't attached to anything.
My multimeter doesn't seem to be able to do feq testing. It's just a simple "tack life" unit that is only able to do resistance, continuity, voltage and diode testing.
EDIT: Using the ohm setting I was able to measure that the inductor is good. Also measured the photo transitor pointed at a light and then away from it and it does respond. On the 2k max setting it shows in the light to register varying from .100 to .125 and of course back to flat reading when in the dark. The inductor on the 200ohm max setting reads at 66.3 which I believe shows it's good if it actually is an inductor.
Last edited by nintendo2600 on Wed Mar 18, 2020 12:36 pm, edited 3 times in total.
Re: Hardware test program for Genesis Justifier, Menacer and\or ALG GAMEGUN?
That's typical for phototransistors. They're "real" transistors, with all three standard pins, but they're explicitly exposed to light instead of isolated. Photons landing on it produce a virtual base current, allow current to flow from collector to emitter.nintendo2600 wrote: ↑Wed Mar 18, 2020 11:20 am The photo transistor is kinda interesting how it's set up. The emitter and collector are attached but the base isn't attached to anything.
Some designs may bias the Base with a fixed voltage ahead of time to get different performance, but usually it doesn't matter.
In hindsight, a better plan is to power the gun, measure the voltage across the phototransistor, and shine a bright light into it. You should see the voltage drop when the light is present.My multimeter doesn't seem to be able to do freq testing.
- nintendo2600
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- Joined: Mon Mar 30, 2009 4:40 pm
Re: Hardware test program for Genesis Justifier, Menacer and\or ALG GAMEGUN?
I edited my post above while you where posting to add more info.lidnariq wrote: ↑Wed Mar 18, 2020 11:35 amThat's typical for phototransistors. They're "real" transistors, with all three standard pins, but they're explicitly exposed to light instead of isolated. Photons landing on it produce a virtual base current, allow current to flow from collector to emitter.nintendo2600 wrote: ↑Wed Mar 18, 2020 11:20 am The photo transistor is kinda interesting how it's set up. The emitter and collector are attached but the base isn't attached to anything.
Some designs may bias the Base with a fixed voltage ahead of time to get different performance, but usually it doesn't matter.
In hindsight, a better plan is to power the gun, measure the voltage across the phototransistor, and shine a bright light into it. You should see the voltage drop when the light is present.My multimeter doesn't seem to be able to do freq testing.