Using a USB keyboard
Posted: 03 Apr 2020, 12:02
I tried to connect a Verbatim 99201 USB keyboard to the Gigatron via Pluggy McPlugface and a PS2-to-USB adapter. The keyboard, which worked fine on my Raspberry Pi, had trouble connecting to the Gigatron. Sometimes it would start working almost immediately (in less than 10 seconds), sometimes it would take 20-50 seconds, but most of the time it wouldn't work at all.
Apart from the keyboard, the Gigatron was working --- the blinkenlights were flashing and the VGA display was fine. The Gigatron would work with the game controller but not with the USB keyboard.
The Pluggy McPlugface manual says that “We have heard success stories of people using a USB keyboard with a converter from USB to PS/2. Whether this works depends on both the converter and the adapter”. It goes on to say “If your keyboard is not working, possible problems are the keyboard or the power. Try another power supply or USB cable. If that doesn’t work, try another keyboard if you can. Also, it might take up to a minute for the keyboard to initialize”.
The power supply I used with the Gigatron was rated at 5V and 3A. The Gigatron, with Pluggy McPlugface and the keyboard was drawing between 90 and 100 mA and the voltage was steady at 5.04V. That gave me confidence that the power supply wasn't the problem.
The game controller worked perfectly every time, so that I had some confidence that Pluggy McPlugface was working. (I ordered a second Pluggy McPlugface just in case, but it hasn't arrived yet).
I was using a green PS2-to-USB adapter. Because the green adapters are intended for use with a mouse, I was concerned that it might not be wired to permit it to work with a keyboard; PS2-to-USB adapters for keyboards are purple in colour. I had read on the Internet that the green and purple adapters were wired differently, but that turned out not to be true.
I tried a purple (keyboard) adapter but the problem remained. I traced how the green (mouse) and purple (keyboard) adapters were wired and found that the adapters are electrically identical; they differ only in colour and markings.
This image provides information about PS/2 and USB connectors and how the PS2-to-USB adapters are wired. I sourced a PS2 keyboard (a Perixx Periboard-409) from Amazon. It worked perfectly as soon as I connected it.
There was very little technical information about the Verbatim 99201 keyboard on Verbatim's website and nothing at all about using it with a PS2 adapter. Rather than tear apart the Verbatim 99201 USB keyboard to investigate why it wasn’t working reliably via PS2, I just decided to use the new PS2 keyboard.
Apart from the keyboard, the Gigatron was working --- the blinkenlights were flashing and the VGA display was fine. The Gigatron would work with the game controller but not with the USB keyboard.
The Pluggy McPlugface manual says that “We have heard success stories of people using a USB keyboard with a converter from USB to PS/2. Whether this works depends on both the converter and the adapter”. It goes on to say “If your keyboard is not working, possible problems are the keyboard or the power. Try another power supply or USB cable. If that doesn’t work, try another keyboard if you can. Also, it might take up to a minute for the keyboard to initialize”.
The power supply I used with the Gigatron was rated at 5V and 3A. The Gigatron, with Pluggy McPlugface and the keyboard was drawing between 90 and 100 mA and the voltage was steady at 5.04V. That gave me confidence that the power supply wasn't the problem.
The game controller worked perfectly every time, so that I had some confidence that Pluggy McPlugface was working. (I ordered a second Pluggy McPlugface just in case, but it hasn't arrived yet).
I was using a green PS2-to-USB adapter. Because the green adapters are intended for use with a mouse, I was concerned that it might not be wired to permit it to work with a keyboard; PS2-to-USB adapters for keyboards are purple in colour. I had read on the Internet that the green and purple adapters were wired differently, but that turned out not to be true.
I tried a purple (keyboard) adapter but the problem remained. I traced how the green (mouse) and purple (keyboard) adapters were wired and found that the adapters are electrically identical; they differ only in colour and markings.
This image provides information about PS/2 and USB connectors and how the PS2-to-USB adapters are wired. I sourced a PS2 keyboard (a Perixx Periboard-409) from Amazon. It worked perfectly as soon as I connected it.
There was very little technical information about the Verbatim 99201 keyboard on Verbatim's website and nothing at all about using it with a PS2 adapter. Rather than tear apart the Verbatim 99201 USB keyboard to investigate why it wasn’t working reliably via PS2, I just decided to use the new PS2 keyboard.