GBAccelerator GBC Operating Instructions

When you first power on your Game Boy Color, it will be running at normal speed. At any time during gameplay you may change the clock speed using the 3 buttons you have connected to the GBAccelerator.  The power LED will indicate which speed is currently selected.

Normal Control Mode:

Press and release all 3 buttons.  Each time you do this, the GBAccelerator will cycle through the different clock speeds:

Fast -> Ultra -> Slow-Motion -> Normal

Up/Down Control Mode:

Hold down the button connected to the GBAccelerator’s S (Select) input, and tap the button connected to U (Up) to increase speed, or D (Down) to decrease speed.  In this mode, the speed doesn’t loop back around.  Pressing and releasing all 3 buttons will return the GBAccelerator to normal speed.

The following table shows the available speeds and their corresponding LED codes:

Mode
Speed
LED
Normal 1x Solid
Fast 1.5x 1 Blink
Ultra 2x 2 Blinks
Slow-Motion 0.66x Fade

 

Disable Ultra Speed

If your system or game has trouble running at Ultra speed (or you do!), you can disable it.  Hold down all 3 GBAccelerator buttons for approximately 6 seconds.  The LED will flash 3 times to indicate that Ultra has been disabled.  You can release the buttons at this point.  Repeating the procedure will re-enable Ultra speed.  GBAccelerator remembers this setting even after the handheld has been turned off.

Enable Up/Down Control Mode

This mode is available on v2 or higher GBAccelerators.  Hold down all 3 GBAccelerator buttons for approximately 12 seconds.  At about 6 seconds, the LED will flash 3 times, but keep holding the buttons.  After 12 seconds the LED will flash 4 times to indicate that up/down mode has been enabled.  You can release the buttons now.  Repeating the procedure will toggle back to normal control mode.  The GBAccelerator will remember this setting even after the handheld has been turned off.