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Are game port joystick button circuits more than plain switches? Is this one just faulty?
Can I build a working(ish) vacuum tube byte?How to create a switchless multi-system 2 button Atari joystick?The almost-was Atari IBM PCConnecting Panasonic “Penwriter” RK-P400C to modern PC using USB to serial cableWhy are C64 games inconsistent with which joystick port they use?
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I'm building a custom interface unit for a game port joystick. To use/test it, I have a CH Products Mach III. (This is the IBM PC version, not the Apple version.) I purchased the joystick for this purpose and have not tested it with an original computer.
I found that the second button was registering as always-pressed. On investigation, there is a resistance of about 60 Ω between "button 2" pin 7 and "ground" pin 4 (pin 5 is absent from the plug) when the button is not pressed, <1 Ω when the button is pressed, and no connection between pin 7 and any other pin. Button 1 behaves more as expected, an open circuit when the button is not pressed.
Is this a special signaling mechanism of some sort, or does it merely indicate that the switch is dirty? (It is not clear how to open the joystick to inspect the circuit, or I would have done this first. Perhaps I'll ask a separate question about that.)
I would ideally like to design the interface unit to be broadly compatible with different models of joysticks (including, possibly, Apple-style joysticks with an alternate socket), so I am preferably looking for expectations on button interfacing, perhaps with recommended (or historical) detection thresholds, not just information about this specific joystick.
ibm-pc joystick old-hardware-adaptation
asked 20 hours ago
Kevin ReidKevin Reid
1286 bronze badges
New contributor
Kevin Reid is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
|
show 3 more comments
I'm building a custom interface unit for a game port joystick. To use/test it, I have a CH Products Mach III. (This is the IBM PC version, not the Apple version.) I purchased the joystick for this purpose and have not tested it with an original computer.
I found that the second button was registering as always-pressed. On investigation, there is a resistance of about 60 Ω between "button 2" pin 7 and "ground" pin 4 (pin 5 is absent from the plug) when the button is not pressed, <1 Ω when the button is pressed, and no connection between pin 7 and any other pin. Button 1 behaves more as expected, an open circuit when the button is not pressed.
Is this a special signaling mechanism of some sort, or does it merely indicate that the switch is dirty? (It is not clear how to open the joystick to inspect the circuit, or I would have done this first. Perhaps I'll ask a separate question about that.)
I would ideally like to design the interface unit to be broadly compatible with different models of joysticks (including, possibly, Apple-style joysticks with an alternate socket), so I am preferably looking for expectations on button interfacing, perhaps with recommended (or historical) detection thresholds, not just information about this specific joystick.
ibm-pc joystick old-hardware-adaptation
asked 20 hours ago
Kevin ReidKevin Reid
1286 bronze badges
New contributor
Kevin Reid is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
As an aside (or, in response to your aside), I feel like I've opened a Mach III (or one of the earlier versions) at some point, and my memory is that there are screws hidden under one or more decals on the underside of the joystick. I could be misremembering, but it's certainly a common enough construction pattern that it's pretty likely. The "slide a screwdriver around on the label and see where it gives" method of detecting the hidden screwholes should probably work just fine.
– FeRD
9 hours ago
Oh, I was close: The screwholes are hidden under the rubber feet.
– FeRD
9 hours ago
The title makes it sound overly broad, as "ever" sets up a quite large frame, especially when it's about computers, isn't it? Mind to cut it down to the issue in question?
– Raffzahn
9 hours ago
@Raffzahn I dunno, your answer demonstrated that it's not really that broad at all. I suppose it could be phrased as "Are game port button input signals ever more than simple high/low..." instead, to exclude Spektre's complex joystick-button constructions.
– FeRD
9 hours ago
@FeRD Well, even sophisticated constructions are still using 'high/low' after all, that's the only output a 244 enforces. So this won't defuse the "ever" part. We should let it up to the OP to turn the title in a more (long time) helpful version, shouldn't we?
– Raffzahn
9 hours ago
|
show 3 more comments
I'm building a custom interface unit for a game port joystick. To use/test it, I have a CH Products Mach III. (This is the IBM PC version, not the Apple version.) I purchased the joystick for this purpose and have not tested it with an original computer.
I found that the second button was registering as always-pressed. On investigation, there is a resistance of about 60 Ω between "button 2" pin 7 and "ground" pin 4 (pin 5 is absent from the plug) when the button is not pressed, <1 Ω when the button is pressed, and no connection between pin 7 and any other pin. Button 1 behaves more as expected, an open circuit when the button is not pressed.
Is this a special signaling mechanism of some sort, or does it merely indicate that the switch is dirty? (It is not clear how to open the joystick to inspect the circuit, or I would have done this first. Perhaps I'll ask a separate question about that.)
I would ideally like to design the interface unit to be broadly compatible with different models of joysticks (including, possibly, Apple-style joysticks with an alternate socket), so I am preferably looking for expectations on button interfacing, perhaps with recommended (or historical) detection thresholds, not just information about this specific joystick.
ibm-pc joystick old-hardware-adaptation
asked 20 hours ago
Kevin ReidKevin Reid
1286 bronze badges
New contributor
Kevin Reid is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
I'm building a custom interface unit for a game port joystick. To use/test it, I have a CH Products Mach III. (This is the IBM PC version, not the Apple version.) I purchased the joystick for this purpose and have not tested it with an original computer.
I found that the second button was registering as always-pressed. On investigation, there is a resistance of about 60 Ω between "button 2" pin 7 and "ground" pin 4 (pin 5 is absent from the plug) when the button is not pressed, <1 Ω when the button is pressed, and no connection between pin 7 and any other pin. Button 1 behaves more as expected, an open circuit when the button is not pressed.
Is this a special signaling mechanism of some sort, or does it merely indicate that the switch is dirty? (It is not clear how to open the joystick to inspect the circuit, or I would have done this first. Perhaps I'll ask a separate question about that.)
I would ideally like to design the interface unit to be broadly compatible with different models of joysticks (including, possibly, Apple-style joysticks with an alternate socket), so I am preferably looking for expectations on button interfacing, perhaps with recommended (or historical) detection thresholds, not just information about this specific joystick.
ibm-pc joystick old-hardware-adaptation
ibm-pc joystick old-hardware-adaptation
asked 20 hours ago
Kevin ReidKevin Reid
1286 bronze badges
New contributor
Kevin Reid is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 20 hours ago
Kevin ReidKevin Reid
1286 bronze badges
New contributor
Kevin Reid is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
edited 23 mins ago
Kevin Reid
asked 20 hours ago
Kevin ReidKevin Reid
1286 bronze badges
New contributor
Kevin Reid is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 20 hours ago
Kevin ReidKevin Reid
1286 bronze badges
asked 20 hours ago
Kevin ReidKevin Reid
1286 bronze badges
1286 bronze badges
New contributor
Kevin Reid is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Kevin Reid is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
As an aside (or, in response to your aside), I feel like I've opened a Mach III (or one of the earlier versions) at some point, and my memory is that there are screws hidden under one or more decals on the underside of the joystick. I could be misremembering, but it's certainly a common enough construction pattern that it's pretty likely. The "slide a screwdriver around on the label and see where it gives" method of detecting the hidden screwholes should probably work just fine.
– FeRD
9 hours ago
Oh, I was close: The screwholes are hidden under the rubber feet.
– FeRD
9 hours ago
The title makes it sound overly broad, as "ever" sets up a quite large frame, especially when it's about computers, isn't it? Mind to cut it down to the issue in question?
– Raffzahn
9 hours ago
@Raffzahn I dunno, your answer demonstrated that it's not really that broad at all. I suppose it could be phrased as "Are game port button input signals ever more than simple high/low..." instead, to exclude Spektre's complex joystick-button constructions.
– FeRD
9 hours ago
@FeRD Well, even sophisticated constructions are still using 'high/low' after all, that's the only output a 244 enforces. So this won't defuse the "ever" part. We should let it up to the OP to turn the title in a more (long time) helpful version, shouldn't we?
– Raffzahn
9 hours ago
|
show 3 more comments
As an aside (or, in response to your aside), I feel like I've opened a Mach III (or one of the earlier versions) at some point, and my memory is that there are screws hidden under one or more decals on the underside of the joystick. I could be misremembering, but it's certainly a common enough construction pattern that it's pretty likely. The "slide a screwdriver around on the label and see where it gives" method of detecting the hidden screwholes should probably work just fine.
– FeRD
9 hours ago
Oh, I was close: The screwholes are hidden under the rubber feet.
– FeRD
9 hours ago
The title makes it sound overly broad, as "ever" sets up a quite large frame, especially when it's about computers, isn't it? Mind to cut it down to the issue in question?
– Raffzahn
9 hours ago
@Raffzahn I dunno, your answer demonstrated that it's not really that broad at all. I suppose it could be phrased as "Are game port button input signals ever more than simple high/low..." instead, to exclude Spektre's complex joystick-button constructions.
– FeRD
9 hours ago
@FeRD Well, even sophisticated constructions are still using 'high/low' after all, that's the only output a 244 enforces. So this won't defuse the "ever" part. We should let it up to the OP to turn the title in a more (long time) helpful version, shouldn't we?
– Raffzahn
9 hours ago
As an aside (or, in response to your aside), I feel like I've opened a Mach III (or one of the earlier versions) at some point, and my memory is that there are screws hidden under one or more decals on the underside of the joystick. I could be misremembering, but it's certainly a common enough construction pattern that it's pretty likely. The "slide a screwdriver around on the label and see where it gives" method of detecting the hidden screwholes should probably work just fine.
– FeRD
9 hours ago
As an aside (or, in response to your aside), I feel like I've opened a Mach III (or one of the earlier versions) at some point, and my memory is that there are screws hidden under one or more decals on the underside of the joystick. I could be misremembering, but it's certainly a common enough construction pattern that it's pretty likely. The "slide a screwdriver around on the label and see where it gives" method of detecting the hidden screwholes should probably work just fine.
– FeRD
9 hours ago
Oh, I was close: The screwholes are hidden under the rubber feet.
– FeRD
9 hours ago
Oh, I was close: The screwholes are hidden under the rubber feet.
– FeRD
9 hours ago
The title makes it sound overly broad, as "ever" sets up a quite large frame, especially when it's about computers, isn't it? Mind to cut it down to the issue in question?
– Raffzahn
9 hours ago
The title makes it sound overly broad, as "ever" sets up a quite large frame, especially when it's about computers, isn't it? Mind to cut it down to the issue in question?
– Raffzahn
9 hours ago
@Raffzahn I dunno, your answer demonstrated that it's not really that broad at all. I suppose it could be phrased as "Are game port button input signals ever more than simple high/low..." instead, to exclude Spektre's complex joystick-button constructions.
– FeRD
9 hours ago
@Raffzahn I dunno, your answer demonstrated that it's not really that broad at all. I suppose it could be phrased as "Are game port button input signals ever more than simple high/low..." instead, to exclude Spektre's complex joystick-button constructions.
– FeRD
9 hours ago
@FeRD Well, even sophisticated constructions are still using 'high/low' after all, that's the only output a 244 enforces. So this won't defuse the "ever" part. We should let it up to the OP to turn the title in a more (long time) helpful version, shouldn't we?
– Raffzahn
9 hours ago
@FeRD Well, even sophisticated constructions are still using 'high/low' after all, that's the only output a 244 enforces. So this won't defuse the "ever" part. We should let it up to the OP to turn the title in a more (long time) helpful version, shouldn't we?
– Raffzahn
9 hours ago
|
show 3 more comments
1 Answer
1
active
oldest
votes
Is this a special signaling mechanism of some sort,
No. Buttons are always on/off mechanics. The PC doesn't have any means to detect anything but high or low, according to the threshold (*1) the input circuit has (*2).
or does it merely indicate that the switch is dirty?
Yes, a dirty switch, a used up one, a broken one, some bad soldering adding a bridge and so on.
P.S.: Here's a real nice detailed page about the GCA.
P.P.S.:
I would ideally like to design the interface unit to accommodate as many joysticks as possible
'as many' as in many different joystick (styles) on a single GCA style interface, or as in many joysticks at the same time? If the later, then the maximum is about 16 pairs, as the address range for joysticks ports is 200h..20Fh with 201h being the default. This is ofc only true if you're designing a classic ISA type card. Going by USB, it's all up to your driver.
*1 - For the 74LS244, as used in the original IBM GCA, requires at least 2.0V to detect a high or less than 0.8V to detect low. Since all pullups are ~5 kOhm this means that a button (including all cabling) should have a resistance less than ~0.9 kOhm when closed and above ~4 kOhm when 'open'. So 60 Ohm for sure mean it's always detected as low or closed.
Of course these values may differ for any of the countless other game port inputs.
*2 - Of course, being a digital input, they could be used for some serial data transmission. But that's way beyond standard button usage.
answered 20 hours ago
RaffzahnRaffzahn
67.6k6 gold badges166 silver badges278 bronze badges
It would be electrically possible for a 60 Ohm resistor to be wired in parallel to the switch: that would produce the measurements obtained. There is no reason for this to be done though, as it wouldn't be compatible with the gameport standard (as explained).
– Kaz
19 hours ago
Not only they could be used for serial data transmission, they have been used for serial data transmission. "Digital" devices such as Logitech Wigman Extreme Digital used serial transmission to send pot and button readings and to support more pots and buttons than the standard interface.
– Justme
19 hours ago
3
some more advanced joysticks had Autorepeat circuitry on fire buttons ... so it could be a gate resistance instead of dirty switch ...
– Spektre
19 hours ago
@Justme I'm well aware of these - still they are not part of the question.
– Raffzahn
18 hours ago
I've edited to revise my wording about "multiple joysticks" — I mean only that I want to avoid gratuitous incompatibility by under-informed design. (For which I appreciate your note about voltage and pullups.)
– Kevin Reid
19 mins ago
add a comment |
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1 Answer
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1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
Is this a special signaling mechanism of some sort,
No. Buttons are always on/off mechanics. The PC doesn't have any means to detect anything but high or low, according to the threshold (*1) the input circuit has (*2).
or does it merely indicate that the switch is dirty?
Yes, a dirty switch, a used up one, a broken one, some bad soldering adding a bridge and so on.
P.S.: Here's a real nice detailed page about the GCA.
P.P.S.:
I would ideally like to design the interface unit to accommodate as many joysticks as possible
'as many' as in many different joystick (styles) on a single GCA style interface, or as in many joysticks at the same time? If the later, then the maximum is about 16 pairs, as the address range for joysticks ports is 200h..20Fh with 201h being the default. This is ofc only true if you're designing a classic ISA type card. Going by USB, it's all up to your driver.
*1 - For the 74LS244, as used in the original IBM GCA, requires at least 2.0V to detect a high or less than 0.8V to detect low. Since all pullups are ~5 kOhm this means that a button (including all cabling) should have a resistance less than ~0.9 kOhm when closed and above ~4 kOhm when 'open'. So 60 Ohm for sure mean it's always detected as low or closed.
Of course these values may differ for any of the countless other game port inputs.
*2 - Of course, being a digital input, they could be used for some serial data transmission. But that's way beyond standard button usage.
answered 20 hours ago
RaffzahnRaffzahn
67.6k6 gold badges166 silver badges278 bronze badges
It would be electrically possible for a 60 Ohm resistor to be wired in parallel to the switch: that would produce the measurements obtained. There is no reason for this to be done though, as it wouldn't be compatible with the gameport standard (as explained).
– Kaz
19 hours ago
Not only they could be used for serial data transmission, they have been used for serial data transmission. "Digital" devices such as Logitech Wigman Extreme Digital used serial transmission to send pot and button readings and to support more pots and buttons than the standard interface.
– Justme
19 hours ago
3
some more advanced joysticks had Autorepeat circuitry on fire buttons ... so it could be a gate resistance instead of dirty switch ...
– Spektre
19 hours ago
@Justme I'm well aware of these - still they are not part of the question.
– Raffzahn
18 hours ago
I've edited to revise my wording about "multiple joysticks" — I mean only that I want to avoid gratuitous incompatibility by under-informed design. (For which I appreciate your note about voltage and pullups.)
– Kevin Reid
19 mins ago
add a comment |
Is this a special signaling mechanism of some sort,
No. Buttons are always on/off mechanics. The PC doesn't have any means to detect anything but high or low, according to the threshold (*1) the input circuit has (*2).
or does it merely indicate that the switch is dirty?
Yes, a dirty switch, a used up one, a broken one, some bad soldering adding a bridge and so on.
P.S.: Here's a real nice detailed page about the GCA.
P.P.S.:
I would ideally like to design the interface unit to accommodate as many joysticks as possible
'as many' as in many different joystick (styles) on a single GCA style interface, or as in many joysticks at the same time? If the later, then the maximum is about 16 pairs, as the address range for joysticks ports is 200h..20Fh with 201h being the default. This is ofc only true if you're designing a classic ISA type card. Going by USB, it's all up to your driver.
*1 - For the 74LS244, as used in the original IBM GCA, requires at least 2.0V to detect a high or less than 0.8V to detect low. Since all pullups are ~5 kOhm this means that a button (including all cabling) should have a resistance less than ~0.9 kOhm when closed and above ~4 kOhm when 'open'. So 60 Ohm for sure mean it's always detected as low or closed.
Of course these values may differ for any of the countless other game port inputs.
*2 - Of course, being a digital input, they could be used for some serial data transmission. But that's way beyond standard button usage.
answered 20 hours ago
RaffzahnRaffzahn
67.6k6 gold badges166 silver badges278 bronze badges
It would be electrically possible for a 60 Ohm resistor to be wired in parallel to the switch: that would produce the measurements obtained. There is no reason for this to be done though, as it wouldn't be compatible with the gameport standard (as explained).
– Kaz
19 hours ago
Not only they could be used for serial data transmission, they have been used for serial data transmission. "Digital" devices such as Logitech Wigman Extreme Digital used serial transmission to send pot and button readings and to support more pots and buttons than the standard interface.
– Justme
19 hours ago
3
some more advanced joysticks had Autorepeat circuitry on fire buttons ... so it could be a gate resistance instead of dirty switch ...
– Spektre
19 hours ago
@Justme I'm well aware of these - still they are not part of the question.
– Raffzahn
18 hours ago
I've edited to revise my wording about "multiple joysticks" — I mean only that I want to avoid gratuitous incompatibility by under-informed design. (For which I appreciate your note about voltage and pullups.)
– Kevin Reid
19 mins ago
add a comment |
Is this a special signaling mechanism of some sort,
No. Buttons are always on/off mechanics. The PC doesn't have any means to detect anything but high or low, according to the threshold (*1) the input circuit has (*2).
or does it merely indicate that the switch is dirty?
Yes, a dirty switch, a used up one, a broken one, some bad soldering adding a bridge and so on.
P.S.: Here's a real nice detailed page about the GCA.
P.P.S.:
I would ideally like to design the interface unit to accommodate as many joysticks as possible
'as many' as in many different joystick (styles) on a single GCA style interface, or as in many joysticks at the same time? If the later, then the maximum is about 16 pairs, as the address range for joysticks ports is 200h..20Fh with 201h being the default. This is ofc only true if you're designing a classic ISA type card. Going by USB, it's all up to your driver.
*1 - For the 74LS244, as used in the original IBM GCA, requires at least 2.0V to detect a high or less than 0.8V to detect low. Since all pullups are ~5 kOhm this means that a button (including all cabling) should have a resistance less than ~0.9 kOhm when closed and above ~4 kOhm when 'open'. So 60 Ohm for sure mean it's always detected as low or closed.
Of course these values may differ for any of the countless other game port inputs.
*2 - Of course, being a digital input, they could be used for some serial data transmission. But that's way beyond standard button usage.
answered 20 hours ago
RaffzahnRaffzahn
67.6k6 gold badges166 silver badges278 bronze badges
Is this a special signaling mechanism of some sort,
No. Buttons are always on/off mechanics. The PC doesn't have any means to detect anything but high or low, according to the threshold (*1) the input circuit has (*2).
or does it merely indicate that the switch is dirty?
Yes, a dirty switch, a used up one, a broken one, some bad soldering adding a bridge and so on.
P.S.: Here's a real nice detailed page about the GCA.
P.P.S.:
I would ideally like to design the interface unit to accommodate as many joysticks as possible
'as many' as in many different joystick (styles) on a single GCA style interface, or as in many joysticks at the same time? If the later, then the maximum is about 16 pairs, as the address range for joysticks ports is 200h..20Fh with 201h being the default. This is ofc only true if you're designing a classic ISA type card. Going by USB, it's all up to your driver.
*1 - For the 74LS244, as used in the original IBM GCA, requires at least 2.0V to detect a high or less than 0.8V to detect low. Since all pullups are ~5 kOhm this means that a button (including all cabling) should have a resistance less than ~0.9 kOhm when closed and above ~4 kOhm when 'open'. So 60 Ohm for sure mean it's always detected as low or closed.
Of course these values may differ for any of the countless other game port inputs.
*2 - Of course, being a digital input, they could be used for some serial data transmission. But that's way beyond standard button usage.
answered 20 hours ago
RaffzahnRaffzahn
67.6k6 gold badges166 silver badges278 bronze badges
edited 9 hours ago
answered 20 hours ago
RaffzahnRaffzahn
67.6k6 gold badges166 silver badges278 bronze badges
answered 20 hours ago
RaffzahnRaffzahn
67.6k6 gold badges166 silver badges278 bronze badges
answered 20 hours ago
RaffzahnRaffzahn
67.6k6 gold badges166 silver badges278 bronze badges
67.6k6 gold badges166 silver badges278 bronze badges
It would be electrically possible for a 60 Ohm resistor to be wired in parallel to the switch: that would produce the measurements obtained. There is no reason for this to be done though, as it wouldn't be compatible with the gameport standard (as explained).
– Kaz
19 hours ago
Not only they could be used for serial data transmission, they have been used for serial data transmission. "Digital" devices such as Logitech Wigman Extreme Digital used serial transmission to send pot and button readings and to support more pots and buttons than the standard interface.
– Justme
19 hours ago
3
some more advanced joysticks had Autorepeat circuitry on fire buttons ... so it could be a gate resistance instead of dirty switch ...
– Spektre
19 hours ago
@Justme I'm well aware of these - still they are not part of the question.
– Raffzahn
18 hours ago
I've edited to revise my wording about "multiple joysticks" — I mean only that I want to avoid gratuitous incompatibility by under-informed design. (For which I appreciate your note about voltage and pullups.)
– Kevin Reid
19 mins ago
add a comment |
It would be electrically possible for a 60 Ohm resistor to be wired in parallel to the switch: that would produce the measurements obtained. There is no reason for this to be done though, as it wouldn't be compatible with the gameport standard (as explained).
– Kaz
19 hours ago
Not only they could be used for serial data transmission, they have been used for serial data transmission. "Digital" devices such as Logitech Wigman Extreme Digital used serial transmission to send pot and button readings and to support more pots and buttons than the standard interface.
– Justme
19 hours ago
3
some more advanced joysticks had Autorepeat circuitry on fire buttons ... so it could be a gate resistance instead of dirty switch ...
– Spektre
19 hours ago
@Justme I'm well aware of these - still they are not part of the question.
– Raffzahn
18 hours ago
I've edited to revise my wording about "multiple joysticks" — I mean only that I want to avoid gratuitous incompatibility by under-informed design. (For which I appreciate your note about voltage and pullups.)
– Kevin Reid
19 mins ago
It would be electrically possible for a 60 Ohm resistor to be wired in parallel to the switch: that would produce the measurements obtained. There is no reason for this to be done though, as it wouldn't be compatible with the gameport standard (as explained).
– Kaz
19 hours ago
It would be electrically possible for a 60 Ohm resistor to be wired in parallel to the switch: that would produce the measurements obtained. There is no reason for this to be done though, as it wouldn't be compatible with the gameport standard (as explained).
– Kaz
19 hours ago
Not only they could be used for serial data transmission, they have been used for serial data transmission. "Digital" devices such as Logitech Wigman Extreme Digital used serial transmission to send pot and button readings and to support more pots and buttons than the standard interface.
– Justme
19 hours ago
Not only they could be used for serial data transmission, they have been used for serial data transmission. "Digital" devices such as Logitech Wigman Extreme Digital used serial transmission to send pot and button readings and to support more pots and buttons than the standard interface.
– Justme
19 hours ago
3
3
some more advanced joysticks had Autorepeat circuitry on fire buttons ... so it could be a gate resistance instead of dirty switch ...
– Spektre
19 hours ago
some more advanced joysticks had Autorepeat circuitry on fire buttons ... so it could be a gate resistance instead of dirty switch ...
– Spektre
19 hours ago
@Justme I'm well aware of these - still they are not part of the question.
– Raffzahn
18 hours ago
@Justme I'm well aware of these - still they are not part of the question.
– Raffzahn
18 hours ago
I've edited to revise my wording about "multiple joysticks" — I mean only that I want to avoid gratuitous incompatibility by under-informed design. (For which I appreciate your note about voltage and pullups.)
– Kevin Reid
19 mins ago
I've edited to revise my wording about "multiple joysticks" — I mean only that I want to avoid gratuitous incompatibility by under-informed design. (For which I appreciate your note about voltage and pullups.)
– Kevin Reid
19 mins ago
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Kevin Reid is a new contributor. Be nice, and check out our Code of Conduct.
Kevin Reid is a new contributor. Be nice, and check out our Code of Conduct.
Kevin Reid is a new contributor. Be nice, and check out our Code of Conduct.
Kevin Reid is a new contributor. Be nice, and check out our Code of Conduct.
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As an aside (or, in response to your aside), I feel like I've opened a Mach III (or one of the earlier versions) at some point, and my memory is that there are screws hidden under one or more decals on the underside of the joystick. I could be misremembering, but it's certainly a common enough construction pattern that it's pretty likely. The "slide a screwdriver around on the label and see where it gives" method of detecting the hidden screwholes should probably work just fine.
– FeRD
9 hours ago
Oh, I was close: The screwholes are hidden under the rubber feet.
– FeRD
9 hours ago
The title makes it sound overly broad, as "ever" sets up a quite large frame, especially when it's about computers, isn't it? Mind to cut it down to the issue in question?
– Raffzahn
9 hours ago
@Raffzahn I dunno, your answer demonstrated that it's not really that broad at all. I suppose it could be phrased as "Are game port button input signals ever more than simple high/low..." instead, to exclude Spektre's complex joystick-button constructions.
– FeRD
9 hours ago
@FeRD Well, even sophisticated constructions are still using 'high/low' after all, that's the only output a 244 enforces. So this won't defuse the "ever" part. We should let it up to the OP to turn the title in a more (long time) helpful version, shouldn't we?
– Raffzahn
9 hours ago