Regarding the jumpers on the Controller Board:
"In the factory set configuration the three position switch of the CONTROLLER will affect the write protect until a software protect/unprotect command is issued, such as from the program options menu of the VARP SPEED SOFTVARE After the protect/unprotect command is issued the three position switch has no effect until that mode is reset. Therefore, in this mode the software has priority over the manual switch.
In the first alternate configuration all three factory jumpers are cut and jumpers are installed in the three adjacent positions. In this mode the software command has effect only when the three position switch is in the NORMAL or down position Thus, in this alternate configuration the manual switch setting has priority over the software command.
In the last alternate configuration the center one of the three factory jumpers is cut, leaving the other two original jumpers. In this mode the manual switch and the disk notch have no effect. Disk writing is prohibited until the unprotect command is issued through software. This can prevent unauthorised writing to disks if only you know how to execute the unprotect command."