Tandy 1000 SL Technical Reference Manual page 183

4C Characteristics (cont)
Ta
=
-10% to +7OoC.
VCC
=
+5 V f 5 % (vPD765An265A) and VCC
=
+5V
f10%
(uPD765A-217265A-2)
Urnb
1651,7265 766A-2,726S-2 TNt
Window cycle time
tWCY
4 4
pS
MFM=O,
5114"
2 2
ps
MFM=l. 5114"
2
2
pS
MFM=O.8"
Panmotor
Srnaol
Yin Typ(i)
Mar Yln
Typ(i]
Max UnH Condltlons
1 1
pS
MFM=1.8"
2
2
pS
MFM=O, 3'/2"(3)
1 1
ps
MFM=l, 3'/2"(3)
Window hold time to RDD
tRDW 15 15 ns
Window hold time from RDD
tWRO
15 15 ns
US0.1 holdtimetowlseekt tu$ 12 12
ps
8 MHz clock period(4)
R W I seek hold time to low
t
S
D 7 7
ps
8 MHz clock period(4)
-
currentldirectiont
Low current I direction hold time to 1 0 s 1.0 1.0
ps
8 MHz clock period(4)
fault reset I step t
USo, 1 hold time from fault reset1 t g u 5.0 5.0
ps
8 MHz clock period(4)
steD
1
Step active time (high)
tSTP
6 7
8 6
7 8
ps
(Note4)
Step cycle time
tSC
33 (Note 2) (Note 2) 33 (Note 2) (Note 2)
ps
(Note4)
Fault reset active time (high)
~ F R
8.0 10 8.0 10
ps
(Note4)
Write data width
~ W D O
10-50 10-50 ns
USo,
1 hold time after seek
tsu
15 15
ps
8 MHz clock period(4)
Seek hold time from DIR tDS 30 30
ps
8 MHz clock period(4)
DIR hold time after step tST0
24
24
ps
8 MHz clock period(4)
RD i M a y from DRO ~ M R
800
800
ns 8 MHz clock period(4)
WRJdelay from DRO
tMW
250 250 ns 8 MHz clock period(4)
Index pulse width
tlDX
4 4
@CY
-
-
WE or
RD
response time from DRO t t M w 12 12
ps
8 MHz clock period(4)
Note:
(1)
Typical values for Tn =
25%
and nominal supply voltage.
(2) Under software control. The range is from
1
ms to 1 6 ms at
8 MHz
clock period, and
2
ms
lo 32
ms at
4 MHz
clock period.
(3) Sony Micro Floppydlsk
Fh"
drive.
(4)
Double thesa values for a 4 MHz clock perlod.
Tlmlng Waveforms
Processor Read Operation
I
Processor Write Operation
6-8