II-112
EPSON
S1C62440/624A0/624C0/62480 TECHNICAL SOFTWARE
CHAPTER 7: SUMMARY OF NOTES
Because at initial reset, the contents of segment data mem-
ory and LC0–LC3 are undefined, there is need to initialize by
software.
(1) When the clock timer has been reset, the interrupt factor
flag (IT) may sometimes be set to "1". Consequently,
perform flag read (reset the flag) as necessary at reset.
(2) Because the watchdog timer counts up during reset as in
the above (1), reset the watchdog timer as necessary.
(3) When the low-order digits (TM0–TM3) and high-order
digits (TM4–TM7) are consecutively read, proper reading
may not be obtained due to the carry from the low-order
digits into the high-order digits (when the reading of the
low-order digits and high-order digits span the timing of
the carry). For this reason, perform multiple reading of
timer data, make comparisons and use matching data as
result.
When data of the counter is read at run mode, perform the
reading after suspending the counter once and then set
SWRUN to "1" again. Moreover, it is required that the sus-
pension period not exceed 976 s (1/4 cycle of 256 Hz).
(1) When initiating programmable timer count, perform
programming by the following steps:
1. Set the initial data to RD0–RD7.
2. Reset the programmable timer by writing "1" to PTRST.
3. Start the down-count by writing "1" to PTRUN.
(2) When the reload register (RD0–RD7) value is set at "00H",
the down-counter becomes a 256-value counter.
(3) When data of the timer is read consecutively in 8 bits in
the RUN mode, perform the reading after suspending the
timer once and then set the PTRUN to "1" again. More-
over, it is required that the suspension period be within
1/4 cycle of the input clock (in case of 1/2 duty). Ac-
cordingly, when the input clock is a fast clock faster than
256 Hz, high speed processing by OSC3 is required.
LCD driver
Stopwatch timer
Programmable timer
Clock timer