nDIR
t3
t4
nSTEP
t1
t2
t9
t5
nDS0-1
nINDEX
t6
t7
t8
nRDATA
nWDATA
FIGURE 17 – FLOPPY DISK DRIVE TIMING (AT MODE ONLY)
NAME
DESCRIPTION
nDIR Set Up to STEP Low
nSTEP Active Time Low
nDIR Hold Time after nSTEP
nSTEP Cycle Time
nDS0-1 Hold Time from nSTEP Low (Note)
nINDEX Pulse Width
nRDATA Active Time Low
nWDATA Write Data Width Low
nDS0-1, Setup Time nDIR Low (Note)
MIN
TYP
4
MAX
UNITS
X*
X*
X*
X*
X*
X*
ns
Y*
t1
t2
t3
t4
t5
t6
t7
t8
t9
24
96
132
20
2
40
.5
0
ns
*X specifies one MCLK period and Y specifies one WCLK period.
MCLK = 16 x Data Rate (at 500 kb/s MCLK = 8 MHz)
WCLK = 2 x Data Rate (at 500 kb/s WCLK = 1 MHz)
Note: The nDS0-1 setup and hold times must be met by software.
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