Epson S1C6S3N2, Техническое руководство

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I-100
EPSON
S1C6S3N2 TECHNICAL HARDWARE
CHAPTER 5: SUMMARY OF NOTES
Consequently, when the input terminal is in the active
status (Low status), do not rewrite the mask register
(clearing, then setting the mask register), so that a factor
flag will only set at the falling edge in this case. When
clearing, then setting the mask register, set the mask
register, when the input terminal is not in the active
status (High status).
When an interrupt is triggered at the rising edge of the
input terminal, a factor flag will be set at the timing of
➁
shown in Figure 5.2.1. In this case, when the mask
registers cleared, then set, you should set the mask
register, when the input terminal is in the Low status.
In addition, when the mask register = "1" and the content
of the differential register is rewritten in the input termi-
nal active status, an input interrupt factor flag may be
set. Thus, you should rewrite the content of the differen-
tial register in the mask register = "0" status.
When BZ, BZ and FOUT are selected with the mask option,
a hazard may be observed in the output waveform when the
data of the output register changes.
(1) When the I/O port is being read out, the in-built pull-
down resistance of the I/O port goes ON. Consequently,
if data is read out while the CPU is running in the OSC3
oscillation circuit, data must be read out continuously for
about 500 µs.
(2) When the I/O port is set to the output mode and the data
register has been read, the terminal data instead of the
register data can be read out. Because of this, if a low-
impedance load is connected and read-out performed, the
value of the register and the read-out result may differ.
(1) When 40H–6FH is selected for the segment data memory,
the memory data and the display will not match until the
area is initialized (through, for instance, memory clear
processing by the CPU). Initialize the segment data
memory by executing initial processing.
Output port
LCD driver
I/O port