Interface; General - Fujitsu M2301B Manual

(8) GAP 2
This is an area where a write splice would occur when the data area of the
sector was updated. Since the read circuit may be reactivated after the write
splice area, all "0" must be written in this 13 or more Byte area. The read
circuit requires an "O"s area to synchronize read circuits.
(9) SYNC BYTE
Indicates the beginning of the data area.
(10) DATA AREA
This is the area where data is written and read.
(11) CRC
See (7)
(12) GAP 3
This is pad time required by the control unit. All "O"s are written in this area.
4.5 INTERFACE
4.5.1 General
Logical and physical conditions for the reception/transmission of signals in the
interface of M2301/M2302 micro disk drive are described in this chapter.
(1) Connection
There are two connectors for external connection on this unit. These are called
"A" and "B" connectors. The cables connected to these are called cable "A"
and cable "B". "A" cables may be connected in daisy chain. When this con-
figuration is utilized, the terminator must be removed from all but the last
drive. See Fig. 3.7. The liB" cable is connected in a radial fashion. Therefore,
the control unit, requires "B" cables and connectors in proportion to the
number of drives connected.
(2) Timing Specification
The timing specifications for signals are referenced at the connector position
of the unit. Consequently, with regard to the signal timing from the unit, time
lag of the cable, and time lag due to the number of circuit stages in the control
unit must be considered.
(3) Interface Transmission Level
There are two types of interface drivers and receivers used. For the high fre-
quency signal lines, balanced line differential devices are used. These lines are
indicated by "(1 pair)" in the digrams below. The control and select lines are
TTL level and 0 volt is active or true.
B03P-4605-0003A .... B 4-9