II-80
EPSON
S1C62740 TECHNICAL SOFTWARE
CHAPTER 7: SUMMARY OF NOTES
(1) When using the serial interface in the master mode, the syn-
chronous clock uses the CPU system clock. Accordingly, do not
change the system clock (fOSC1
fOSC3) while the serial inter-
face is operating.
(2) Perform data writing/reading to data registers SD0–SD7 only
while the serial interface is halted (i.e., the synchronous clock is
neither being input or output).
(3) As a trigger condition, it is required that data writing or reading
on data registers SD0–SD7 be performed prior to writing "1" to
SCTRG. (The internal circuit of the serial interface is initiated
through data writing/reading on data registers SD0–SD7.)
Supply trigger only once every time the serial interface is placed
in the RUN state. Moreover, when the synchronous clock SCLK
is external clock, start to input the external clock after the
trigger.
(4) SCTRG can be read or write. After write "1" to SCTRG, it will
still high until serial data been shift in or out completely.
Serial interface
Amplifier (1) It takes about 3 msec for the AMP0 or AMP1 output becomes
stable when the circuit is turned on. Therefore, the program
must include a wait time of at least 3 msec before the output
data is loaded after the AMP1 or AMP0 circuit has been turned
on.
(2) The AMPDT1(0) is undefined when the AMPP1(0) or AMPM1(0) is
disconnected, and is "0" when AMPON1(0) is "0".
After an initial reset, this bit is set to "0".
(3) To reduce current consumption, set the AMP circuit to OFF
when it is not necessary.
A/D converter (1) To reduce current consumption, set the reference voltage
generation circuit, the middle electric potential generation
circuit and the A/D converter to OFF when it is not necessary.
(2) Do not fail to select the correct combinations for the analog
input terminal and measurement items. (Refer to Table 6.13.4)
(3) To perform a stable A/D conversion, secure the decided wait
time.
(4) Be sure to check whether the data is effective or invalid by
reading the A/D conversion data in the order F7H
→ F8H →
F9H
→ FAH and immediately thereafter reading the IDR (FBH).