
II-92
EPSON
S1C62N82 TECHNICAL SOFTWARE
CHAPTER 4: SUMMARY OF PROGRAMMING POINTS
LCD Driver
– Becase the LCD RAM can be read and written, so data
can be changed directly using an ALU instruction (for
example, AND or OR).
– Because at initial reset, the contens of segment data
memory are undefined, there are need to initialize by
software.
– Even in case 1/4 duty were selected, when SEG terminal
is set to static driving, set the same values on all the
display memories corresponding to COM0–COM7.
Analog Comparator
Data in the CMPDT register becomes "1" when CMPON is
"0" (analog comparator circuit is off), and undefined when
the CMPP and/or CMPM input is disconnected. Avoid
reading operation under those conditions.
Supply Voltage Detec-
tion (SVD) Circuit
Since supply voltage detection is automatically performed
by the hardware every 2 Hz (0.5 sec) when the heavy load
protection function operates, do not permit the operation
of the SVD circuit by the software in order to minimize
power current consumption.
In the heavy load protection function (heavy load protec-
tion mode flag = "1"), supply voltage detection through
the SVDON register is not permitted in order to minimize
power current consumption.
Heavy Load Protec-
tion Function
– Even when the contents of the input data and input
comparator register change from an unmatched state to
another unmatched state or to a matched state, no
interrupt will occur.
– Re-start from the HALT state is performed by the inter-
rupt. The return address after completion of the interrupt
processing in this case will be the address following the
HALT instruction.
– When interrupt occurs, the interrupt flag will be reset by
the hardware and it will become DI state. After comple-
tion of the interrupt processing, set to the EI state
through the software as needed.
Moreover, the nesting level may be set to be program-
mable by setting to the EI state at the beginning of the
interrupt processing routine.
Interrupt