Intel 8253 - Page 98

80C187
AC Characteristics
T
C
e
0
§
Cto
a
85
§
C, V
CC
e
5V
g
10%
All timings are measured at 1.5V unless otherwise specified
12.5 MHz 16 MHz
Test
Symbol Parameter Min Max Min Max Conditions
(ns) (ns) (ns) (ns)
T
dvwh
(t6) Data Setup to NPWR 43 33
T
whdx
(t7) Data Hold from NPWR 14 14
T
rlrh
(t8) NPRD Active Time 59 54
T
wlwh
(t9) NPWR Active Time 59 54
T
avwl
(t10) Command Valid to NPWR 00
T
avrl
(t11) Command Valid to NPRD 00
T
mhrl
(t12) Min Delay from PEREQ Active 40 30
to NPRD
Active
T
whax
(t18) Command Hold from NPWR 12 8
T
rhax
(t19) Command Hold from NPRD 12 8
T
ivcl
(t20) NPRD, NPWR
, RESET to 46 38 Note 1
CLK Setup Time
T
clih
(t21) NPRD, NPWR, RESET from 26 18 Note 1
CLK Hold Time
T
rscl
(t24) RESET to CLK Setup 21 19 Note 1
T
clrs
(t25) RESET from CLK Hold 14 9 Note 1
T
cmdi
(t26) Command Inactive Time
Write to Write 69 59
Read to Read 69 59
Read to Write 69 59
Write to Read 69 59
NOTE:
1. This is an asynchronous input. This specification is given for testing purposes only, to assure recognition at a specific CLK
edge.
22