Echelon FT 3150 Smart Transceiver - Manual (Page 74)

Chapter 3 - Input/Output Interfaces
68 FT 3120 / FT 3150 Smart Transceiver Data Book
Figure 3.33 Touch I/O Object
The leveldetect input object can be used for detection of asynchronous attachments of Touch Memory devices to the
FT Smart Transceiver. In such a case, the leveldetect input object is overlaid on top of the Touch I/O object. Refer to
the Neuron C Programmer’s Guide for information on I/O object overlays.
Symbol Description Min Typ Max
t
rsto
Reset call to data line low — 60.0 µs —
t
rstl
Reset pulse width — 500 µs —
t
pdh
Reset pulse release to data line high
10MHz
5MHz
4.8 µs
9.6 µs —
— 275 µs
275 µs
t
pdl
Presence pulse width — 120.0 µs —
t
wh
Data line high detect to presence pulse — 80 µs —
t
rret
Return from reset function — 12.6 µs —
t
f
I/O call to data line low (start of bit slot) — 125.4 µs —
t
low
Start pulse width
10MHz
5MHz
—
— 4.2 µs
8.4 µs —
—
t
rdi
Start pulse edge to sampling of input (read operation)
10MHz
5MHz
—
— 15.0 µs
18.0 µs —
—
t
wrd
Start pulse edge to FT Smart Transceiver releasing the data line
10MHz
5MHz
—
— 66.6 µs
72.0 µs —
—
t
ibd
Inter-bit delay
10MHz
5MHz
—
— 61.2 µs
122.4 µs —
—
t
ret
Return from I/O call — 42.6 µs —
TIME
DATA LINE
t
rsto
START OF
touch_reset()
INPUT
SAMPLED
t
pd
t
pdl
t
rret
NEXT
io_in() OR
io_out()
TIME
START OF io_in() OR
io_out()
INPUT
SAMPLED
t
f
END OF
io_in() OR
io_out()
t
low
t
ibd
t
wrd
t
rdi
t
ret
DATA LINE
DATA LINE
DATA LINE
RESET
AND
PRESENCE
WRITE 1
WRITE 0
READ
FT Smart Transceiver
TOUCH MEMORY
PULL-UP RESISTOR
LINE TYPE LEGEND
IO10
IO9
IO8
IO0
IO1
IO2
IO3
IO4
IO5
IO6
IO7
END OF
touch_reset()
t
rstl
t
wh
High Current Sink Drivers