2.3.2
Track 00 (J1 pin #26)
An active low on this signal line indicates that the read/write head is positioned at
track zero (the outermost track). This signal is at a logic high when the read/write
head is not at track zero. When the read/write head is at track zero and an additonal
step-out pulse is issued to the drive, the microprocessor logic will keep the read/write
head positioned at track zero.
2.3.3
Write protect (J1 pin #28)
An active low level on this signal line idicates that a write-protected diskette has
been installed. The drive will inhibit writing on a write-protected diskette and
additionally notifies the host system.
2.3.4
Read data (J1 pin #30)
This interface line provides that the data from the diskette is outputed to the host
system. Each flux reversal that is sensed on the diskette produces a transistion to
an active low level. In standard configuration, when the GX plug is installed, the
read data signal is inhibited as long as the drive is "internally" not ready (i.e. either
the carriage is seeking or the head has not settled on a track). Please also see the
GX plug option section.
2.3.5
Ready/drive status (J1 pin #34)
This interface signal informs the host system about the status of the drive. By
choosing appropriate plug options (RDY/DC/DD/TH plugs), the following conditions
of pin #34 could be achieved. Please see section 3.2.7.
1. Ready : (RDY/TH installed, DISC CHANGE opened).
Pin #34 is active low when a diskette is properly inserted, the drive motor is up
to speed and more than two INDEX pulses are detected. This signal goes to
an inactive high level when "MOTOR ON" is high (inactive).
2. Disk change 1 : (DC installed, DD/TH/RDY opened).
Pin #34 is latched low by "DRIVE SELECT" during power-up or when a
diskette is not inserted.
Pin #34 is latched low by the first "DRIVE SELECT" after the drive is powered
up and the diskette is changed. (Please refer to the diagram overleaf).
The "step" resets pin #34 to a high level.
3. Disk change 2 : (DC/DD/TH installed, RDY opened).
Pin # 34 is latched low during power up or when a diskette is not inserted. To
unlatch the logical level, the drive has to be deselected from a selected state
while a diskette is inserted and the drive is powered up.
4. Disk in : (TH installed, RDY/DC/DD opened).
Pin #34 is a direct function of the disk-insert status. It is active low when a
diskette is inserted.
5. Disk out : (RDY/DC/TH installed, DD opened).
Pin #34 is a direct function of the disk-insert status. It is active low when a
diskette is not inserted.
13
Leaflet No. 9419 26/4/97 6:09 pm Page 13
