Directly access the VGA pins on linux
My motherboard has a VGA output port, just like this one.
Let's say I want to directly access the state of each of the pins on this connector, so that I could control some electronic device, is there any way I can do this?
I'm on Linux, and my first thought was to have a look in /sys/class/, since I know from there I can control certain LEDs on my keyboard, and such. Interestingly, I found a folder called gpio, but I can't any information about how to use that (since I'm not on a raspberry Pi, or anything, I don't have GPIO pins to my knowledge.)
So, is there any way to control the state of individual VGA pins?
linux vga
asked Feb 17 at 13:55
Jacob GarbyJacob Garby
1083
add a comment |
My motherboard has a VGA output port, just like this one.
Let's say I want to directly access the state of each of the pins on this connector, so that I could control some electronic device, is there any way I can do this?
I'm on Linux, and my first thought was to have a look in /sys/class/, since I know from there I can control certain LEDs on my keyboard, and such. Interestingly, I found a folder called gpio, but I can't any information about how to use that (since I'm not on a raspberry Pi, or anything, I don't have GPIO pins to my knowledge.)
So, is there any way to control the state of individual VGA pins?
linux vga
asked Feb 17 at 13:55
Jacob GarbyJacob Garby
1083
VGA is not a GPIO port. It’s not even a digital output.
– Daniel B
Feb 17 at 14:05
@DanielB I know it's not a GPIO port.
– Jacob Garby
Feb 17 at 14:32
1
electronics.stackexchange.com/questions/61290/…
– xenoid
Feb 17 at 17:02
@xenoid Thanks! Those answers look good, but if I need to use something like that I'll just try to make the adapter myself :)
– Jacob Garby
Feb 17 at 17:34
add a comment |
My motherboard has a VGA output port, just like this one.
Let's say I want to directly access the state of each of the pins on this connector, so that I could control some electronic device, is there any way I can do this?
I'm on Linux, and my first thought was to have a look in /sys/class/, since I know from there I can control certain LEDs on my keyboard, and such. Interestingly, I found a folder called gpio, but I can't any information about how to use that (since I'm not on a raspberry Pi, or anything, I don't have GPIO pins to my knowledge.)
So, is there any way to control the state of individual VGA pins?
linux vga
asked Feb 17 at 13:55
Jacob GarbyJacob Garby
1083
My motherboard has a VGA output port, just like this one.
Let's say I want to directly access the state of each of the pins on this connector, so that I could control some electronic device, is there any way I can do this?
I'm on Linux, and my first thought was to have a look in /sys/class/, since I know from there I can control certain LEDs on my keyboard, and such. Interestingly, I found a folder called gpio, but I can't any information about how to use that (since I'm not on a raspberry Pi, or anything, I don't have GPIO pins to my knowledge.)
So, is there any way to control the state of individual VGA pins?
linux vga
linux vga
asked Feb 17 at 13:55
Jacob GarbyJacob Garby
1083
asked Feb 17 at 13:55
Jacob GarbyJacob Garby
1083
asked Feb 17 at 13:55
Jacob GarbyJacob Garby
1083
asked Feb 17 at 13:55
Jacob GarbyJacob Garby
1083
asked Feb 17 at 13:55
Jacob GarbyJacob Garby
1083
1083
VGA is not a GPIO port. It’s not even a digital output.
– Daniel B
Feb 17 at 14:05
@DanielB I know it's not a GPIO port.
– Jacob Garby
Feb 17 at 14:32
1
electronics.stackexchange.com/questions/61290/…
– xenoid
Feb 17 at 17:02
@xenoid Thanks! Those answers look good, but if I need to use something like that I'll just try to make the adapter myself :)
– Jacob Garby
Feb 17 at 17:34
add a comment |
VGA is not a GPIO port. It’s not even a digital output.
– Daniel B
Feb 17 at 14:05
@DanielB I know it's not a GPIO port.
– Jacob Garby
Feb 17 at 14:32
1
electronics.stackexchange.com/questions/61290/…
– xenoid
Feb 17 at 17:02
@xenoid Thanks! Those answers look good, but if I need to use something like that I'll just try to make the adapter myself :)
– Jacob Garby
Feb 17 at 17:34
VGA is not a GPIO port. It’s not even a digital output.
– Daniel B
Feb 17 at 14:05
VGA is not a GPIO port. It’s not even a digital output.
– Daniel B
Feb 17 at 14:05
@DanielB I know it's not a GPIO port.
– Jacob Garby
Feb 17 at 14:32
@DanielB I know it's not a GPIO port.
– Jacob Garby
Feb 17 at 14:32
1
1
electronics.stackexchange.com/questions/61290/…
– xenoid
Feb 17 at 17:02
electronics.stackexchange.com/questions/61290/…
– xenoid
Feb 17 at 17:02
@xenoid Thanks! Those answers look good, but if I need to use something like that I'll just try to make the adapter myself :)
– Jacob Garby
Feb 17 at 17:34
@xenoid Thanks! Those answers look good, but if I need to use something like that I'll just try to make the adapter myself :)
– Jacob Garby
Feb 17 at 17:34
add a comment |
1 Answer
1
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votes
You can directly control the state of exactly two pins, namely the clock and data pins for the I2C bus used for EDID. See pinout.
However, unless you use an electronic device which itself is controlled by I2C (there are plenty, for example I2C expanders like the MCP23008 or MCP23017, which give you 8 resp. 16 signals you can then control directly via the I2C bus), you'll have to modify your existing video driver to give you an API where you can directly set the state.
You can indirectly control the red, green, blue and the two sync pins in a repeating, time-dependent way, by programming your VGA controller with the timing and writing bit patterns in the frame buffer. This may or may not be useful, depending on what you want to do with it.
answered Feb 17 at 17:55
dirktdirkt
9,47431222
add a comment |
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You can directly control the state of exactly two pins, namely the clock and data pins for the I2C bus used for EDID. See pinout.
However, unless you use an electronic device which itself is controlled by I2C (there are plenty, for example I2C expanders like the MCP23008 or MCP23017, which give you 8 resp. 16 signals you can then control directly via the I2C bus), you'll have to modify your existing video driver to give you an API where you can directly set the state.
You can indirectly control the red, green, blue and the two sync pins in a repeating, time-dependent way, by programming your VGA controller with the timing and writing bit patterns in the frame buffer. This may or may not be useful, depending on what you want to do with it.
answered Feb 17 at 17:55
dirktdirkt
9,47431222
add a comment |
You can directly control the state of exactly two pins, namely the clock and data pins for the I2C bus used for EDID. See pinout.
However, unless you use an electronic device which itself is controlled by I2C (there are plenty, for example I2C expanders like the MCP23008 or MCP23017, which give you 8 resp. 16 signals you can then control directly via the I2C bus), you'll have to modify your existing video driver to give you an API where you can directly set the state.
You can indirectly control the red, green, blue and the two sync pins in a repeating, time-dependent way, by programming your VGA controller with the timing and writing bit patterns in the frame buffer. This may or may not be useful, depending on what you want to do with it.
answered Feb 17 at 17:55
dirktdirkt
9,47431222
add a comment |
You can directly control the state of exactly two pins, namely the clock and data pins for the I2C bus used for EDID. See pinout.
However, unless you use an electronic device which itself is controlled by I2C (there are plenty, for example I2C expanders like the MCP23008 or MCP23017, which give you 8 resp. 16 signals you can then control directly via the I2C bus), you'll have to modify your existing video driver to give you an API where you can directly set the state.
You can indirectly control the red, green, blue and the two sync pins in a repeating, time-dependent way, by programming your VGA controller with the timing and writing bit patterns in the frame buffer. This may or may not be useful, depending on what you want to do with it.
answered Feb 17 at 17:55
dirktdirkt
9,47431222
You can directly control the state of exactly two pins, namely the clock and data pins for the I2C bus used for EDID. See pinout.
However, unless you use an electronic device which itself is controlled by I2C (there are plenty, for example I2C expanders like the MCP23008 or MCP23017, which give you 8 resp. 16 signals you can then control directly via the I2C bus), you'll have to modify your existing video driver to give you an API where you can directly set the state.
You can indirectly control the red, green, blue and the two sync pins in a repeating, time-dependent way, by programming your VGA controller with the timing and writing bit patterns in the frame buffer. This may or may not be useful, depending on what you want to do with it.
answered Feb 17 at 17:55
dirktdirkt
9,47431222
answered Feb 17 at 17:55
dirktdirkt
9,47431222
answered Feb 17 at 17:55
dirktdirkt
9,47431222
answered Feb 17 at 17:55
dirktdirkt
9,47431222
9,47431222
add a comment |
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VGA is not a GPIO port. It’s not even a digital output.
– Daniel B
Feb 17 at 14:05
@DanielB I know it's not a GPIO port.
– Jacob Garby
Feb 17 at 14:32
1
electronics.stackexchange.com/questions/61290/…
– xenoid
Feb 17 at 17:02
@xenoid Thanks! Those answers look good, but if I need to use something like that I'll just try to make the adapter myself :)
– Jacob Garby
Feb 17 at 17:34