ꢀ ꢁ ꢂꢃ ꢄ ꢅ ꢆꢃ ꢅ
ꢇ ꢈꢉ ꢈꢊꢋ ꢌ ꢀꢈ ꢉꢍ ꢋ ꢌ ꢎ ꢏꢐ ꢆꢑ ꢀꢀ ꢐꢏ
SGUS014H − FEBRUARY 1991 − REVISED JUNE 2004
changing XFx from an output to an input
The following table defines the timing parameters for changing the XFx pin from an output pin to an input pin.
timing parameters of XFx changing from output to input mode (see Figure 18)
320C30-40
320C30-50
†
NO.
UNIT
MIN
MAX
MIN
MAX
12*
46
47
48
t
t
t
Delay time, XFx after H3 high
Setup time, XFx before H1 low
Hold time, XFx after H1 low
13*
ns
ns
ns
d(H3H-XFx)
su(XFx-H1L)
h(H1L-XFx)
9
0
9
0
†
Numbers in this column match those used in Figure 18.
* This parameter is not production tested.
Value on
Terminal
Seen in IOF
Buffers Go
From Output
to Input
Execute
Load of IOF
Synchronizer
Delay
H3
H1
47
48
I/OXFx Bit
(see Note A)
46
XFx
Output
INXFx Bit
(see Note A)
Data
Sampled
Data
Seen
NOTE A: I/OXFx represents either bit 1 or bit 5 of the IOF register, and INXFx represents either bit 3 or bit 7 of the IOF register depending on
whether XF0 or XF1, respectively, is being affected.
Figure 18. Timing for Change of XFx From Output to Input Mode
26
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