S-7760A Datasheet, PDF (17/53 Pages) Seiko Instruments Inc – PROGRAMMABLE PORT CONTROLLER (PORT EXPANDER WITH BUILT-IN E2PROM CIRCUIT)

PROGRAMMABLE PORT CONTROLLER (PORT EXPANDER WITH BUILT-IN E²PROM CIRCUIT)
Rev.1.3_00
S-7760A
„ Condition to Start Timer
Table 13 Condition to Start Timer
Option
1
2
Condition
A
B
C
D
Reload
Start → Finish
Regular status
Regular status
Regular status
TIMEN Pin
“H”
“L” → “H”
“H”
Don’t care
Bit TEN3 to 0
Don’t care
Don’t care
Write “0” → “1”
Write “0” → “1”
2 types of options are available for the condition to start a timer. Select either for each digital output port DO0 to 3;
if selecting option 1, the condition to start a timer is three, A/B/C.
If in option 2, the condition is D only. In D, the S-7760A does not react to reload and rising of TIMEN. By writing “1” in TEN,
not in TIMEN, the timer starts.
During power-on of power supply VCCH, the S-7760A automatically reloads (transmits data from the E²PROM to the
register). In this case, TIMEN = “H” and it is in option 1, the S-7760A goes in the timer action after reloading. Thus the
sequential action is; after power-on of power supply VCCH, reload → timer. This is as well if the status changed from
detection to release of the low power supply voltage.
The timer action does not stop in the middle of its process even if setting TIMEN in “H” → “L” after the timer action has
started. In selecting “the option for internal oscillation circuit”, the oscillation circuit is generally being stopped, but the
oscillation starts when the condition to start a timer matches. And it stops by finishing the timer action (the final invert of
output).
Seiko Instruments Inc.
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