NEC PC-8201 - Page 56

(If thc CI'U (80C85) is abnormal, see Item 6.2.3 "Abnormal CI'U".)
5.2.4 CPU Clock Operation Test
hleasure U 17, 80C85, (P37) of the CI'U clock.
Figure
5.5 shows the signal at U 17 (P37).
I 0.25ps
Figure 5.5 U17 (P37) Output Signal
*
If CPU CLOCK is abnormal. see Itern 6.2.4.
5.2.5 Calendar Cloclc Operation Test
hleasure whether
the signal in Figure 5.6 is being transmitted to U20 (P10) of calendar
clock.
I 4ms I
Figure 5.6 Calendar Clock Signal
(Reference ) Figure 5.7 "Calendar Clock Peripheral Circuit"
*
If the calendar clock is abnormal, see Item 6.2.5 "Abnormal Calendar Clock".
1 I 1 ' 32~768K ::I3 3-MR-2
RESET 9-CHI-9
9-CHI-4
I
1 KEY INT 1.U17-7
Figure 5.7 Calendar Clock Peripheral Circuit