When converting a cabinet to use with MAME or other PC applications, you tend to find yourself hacking up a lot of cables, so that you can connect it to something like a GP-Wiz or I-PAC. Similarly to the J-PAC, the USBlinx is intended to remove that burden when using a JAMMA cabinet by allowing you to retain the original wiring and plugging the USBlinx directly into the JAMMA interface.
As described by UltraCade, the USBlinx is an interface for PC based systems to standard arcade controls. It supports 4 players with 4 buttons each, or 2 players with 6 buttons each. Additionally, it supports 2 trackballs and a spinner, making it an rather comprehensive solution to the PC interface problem.
All of the buttons and gadgets which you’d normally not be able to connect through JAMMA can be directly attached the USBlinx. While the USBlinx does have the option to use PS/2 for the keyboard inputs, the recommended connection is via USB, which gives you the un-ghosted keyboard inputs plus the trackball and spinner inputs as well. Since it is either a standard PS/2 device or a standard HID USB device, there’s no software required, and it will therefore support Mac, Windows, Linux, etc.
Other features include a built in audio amplifier for connecting your computer’s audio output to the built in speakers, a video pass through for connecting to the monitor, and a watchdog circuit to reset after a crash. Overall, it sounds pretty comprehensive.
The USBlinx package included all of the following:
Everything was well packed, especially the board itself,
which was protected in an anti-static bag inside of a padded envelope.
Installation is fairly painless. You connect the USBlinx
to the JAMMA harness, and then connect whichever cables you need (audio,
USB, power, etc). The USBlinx can take power from either a 4-pin molex
connector from your PC’s power supply, or it can simply use the
power on the JAMMA harness, if you have an arcade power supply installed
in your cabinet. Their manual states clearly that you cannot connect both
power sources at the same time.
It must be toggled at least once every 30 seconds, or it assumes failure and issues the reset. When testing, I didn’t have the reset cable connected, as there’s little need for it on the workbench. I also was not cycling the numlock state, and so the device would seem to “disconnect and reconnect” every 30 seconds. I went through several test machines before determining the cause of the problem. Downloading a small program that toggles the numlock LED automatically completely resolved this issue, but it is definitely worth mentioning, considering how much time I lost due to this.
There is nothing to configure on the USBlinx, so once everything is connected, you simply turn it on and use it. The key maps for the controls are not adjustable, unlike some of the other devices out there. The key map is shown below, and is included in their manual.
The USBLinx keymap - click for a larger image
The VGA input of the USBlinx passes video directly through to the JAMMA harness (and therefore your monitor) without any conversion or frequency adjustment, etc. If you are using it with an arcade monitor, your video card needs to output the appropriate frequencies. As reviewed in a separate article UltraCade makes a device called the uVC, which converts VGA to arcade frequencies, and does so quite nicely. It would be nice to see that as a feature on the USBlinx, or as an upgrade.
The USBlinx includes a built in 2x37W audio amplifier, and the design appears to be a good one. I didn’t notice any distortion at all during my testing. Unfortunately, there is no adjustment for the volume of the amplifier, requiring you to adjust the sound solely from your computer. It would be nice to see a small pot on the board to adjust how much amplification is being done. The amplifier is definitely nice and loud however. I had to place my computer’s volume at around 5% to have a comfortable sound level in a quiet room. Obviously this would need to be higher in a setting with a lot of background noise, and so I would expect the unit could deliver more than enough sound no matter what your needs were.
The USBlinx supports 4 digital outputs, designed for use with coin lockout solenoids and coin counters, as you’d find in most arcade cabinets. These work as expected, and are a nice feature.
Despite my best efforts, I couldn’t get the device to display any ghosting problems. So this is obviously (as mentioned in the manual) a non-issue. While the unit does include a PS/2 connector for use when you have no USB, it is for exactly that; only when you have no USB available. The USB connector carries both keyboard and mouse data, and is a more reliable way to connect the USBlinx to your computer. If you opt to not use the USB connector at all, you lose the trackball and spinner functionality, as it is only available on the USB connector.
After re-mapping some MAME keys, the unit was a lot more useful. As I said earlier, the default configuration has no way to leave MAME or to insert a credit.
While I did test the VGA pass through capabilities of the USBlinx, my testing was done primarily with an standard resolution arcade monitor. As such, I opted to use the UltraCade uVC instead of the VGA built into the USBlinx.
The USBlinx does exactly what it’s advertised to do. Unfortunately, that’s probably not directly in line with what I believe most home arcade users would like. The non-MAME key map presents a minor irritation for most cabinet setups, but can be worked around by reconfiguring the programs you intend to use. The VGA output not having conversion seems odd, since most video cards don’t do well with arcade frequencies, and the company does offer their separate uVC card that handles this problem perfectly.