Disk Change Signal Timing; Vfo Synchronization (Syc) - NEC FD1165 Maintenance Manual

Figure 3-8
3.5 VFO INTERFACE SIGNALS
The optional VFO
following sections.
3.5.1 Modified Frequency Modulation Mode (MFM)
The MFM signal is Low when MFM data is read or written.
line is High when FM data is read or written.
3.5.2

VFO Synchronization (SYC)

The SYC signal goes Low when read data is synchronized by
the VFO circuit.
3.5.3 Standardized Read Data (SRD)
The SRD line conveys Standardized Read Data.
synchronized by the VFO circuit to make it easily and more
reliably read.
3.5.4 Window (WID)
The controller uses the WID signal to distinguish between
clock pulses and data output by phase-matching the Window
signal with the Standardized Read Data signal.
shows the timing relationship between the signals.
data splice point is passed, timing becomes irregular until
the VFO is resynchronized.

Disk Change Signal Timing

interface signals
3-9
are described
The data is
Figure 3-9
Once the
in the
The