Specifications

S1C62N82 TECHNICAL SOFTWARE EPSON II-17
CHAPTER 3: PERIPHERAL CIRCUITS (Oscillation Circuit)
– It takes at least 5 ms from the time the OSC3 oscillation circuit
goes ON until the oscillation stabilizes. Consequently, when
switching the CPU operation clock from OSC1 to OSC3, do this
after a minimum of 5 ms have elapsed since the OSC3 oscilla-
tion went ON.
Further, the oscillation stabilization time varies depending on
the external oscillator characteristics and conditions of use, so
allow ample margin when setting the wait time.
– When switching the clock from OSC3 to OSC1, use a separate
instruction for switching the OSC3 oscillation OFF.
– To lessen current consumption, keep OSC3 oscillation OFF
except when the CPU must be run at high speed. Also, with
S1C62N82/62L82, keep OSCC fixed to "0".
Note
Examples of oscilla-
tion circuit control
program
• Switching from OSC1 to OSC3 (At fosc1 = 32.768 kHz)
Label Mnemonic/operand Comment
OS3: LD X,0FCH ;Set OSC3 to ON
OR MX,0100B
;
LD A,0EH ;Delay of 5.28 ms: preparation
OS3DLP:ADD A,0FH ;Loop for delay
JP NZ,OS3DLP ;
;
OR MX,1000B ;Switch the CPU clock to OSC3
RET ;Return to parent routine
This subroutine first sets OSC3 to ON, and then, after about
5 ms, switches the CPU clock to OSC3.
A 5.28 ms delay is specified before switching to OSC3, to allow
time for the oscillation circuit to stabilize.
Note