TEAC FD-55B Floppy Drive Jumpers for the AT&T UNIX PC

UNIX PC Jumpers in position

DS0 - Drive Select 0

HM - The head is selected by the signal MOTOR ON.

IU - signal interface line #4 IN-USE input signal = Indicator LED turn-on condition 

                                                                               Drive Select + In-Use

SM - SM allows the use of jumpers HS or HM.

PM - The spindle motor will rotate at the time the floppy is installed.

https://retrocmp.de/fdd/teac/TEAC_FD-55_Jumper-settings.pdf

To use with Jim Drew's SuperCard Pro, must change jumper DS0 to DS1

Set at DS0

Set at DS1