ES51963
4 1/2 DMM
buzzer frequency is determined by the following formula:
fosc1
40 × F1 (B2, B1, B0)
fbuz =
ꢀꢀ(Hz)
where,
fosc1 : ES51963 operating frequency.
fbuz : the frequency of BUZout.
B2, B1, B0 : control bits provided by external microprocessor.
F1( . ) : the fbuz's ratio which is defined in the following table.
According to the formula, a user can select a favorite buzzer frequency among the
audible frequency range. The values of B2, B1 and B0 are 0, 1 and 0 respectively in default.
The buzzer frequencies and the ratios determined by B2, B1 and B0 with various operating
frequencies are shown in the following table.
fbuz
fosc1
6M
4M
2M 1.2M 1M 800k 600k 400k
F1( . )
B2 B1 B0
1 1 1
1 1 0
1 0 1
1 0 0
0 1 1
0 1 0
0 0 1
0 0 0
3
5
50.00 33.33 16.67 10.00 8.33 6.67 5.00 3.33
30.00 20.00 10.00 6.00 5.00 4.00 3.00 2.00
16.67 11.11 5.56 3.33 2.78 2.22 1.67 1.11
10.00 6.67 3.33 2.00 1.67 1.33 1.00 0.67
5.00 3.33 1.67 1.00 0.83 0.67 0.50 0.33
3.00 2.00 1.00 0.60 0.50 0.40 0.30 0.20
1.67 1.11 0.56 0.33 0.28 0.22 0.17 0.11
1.00 0.67 0.33 0.20 0.17 0.13 0.10 0.07
Unit : fosc1 : Hz , fbuz : kHz
9
15
30
50
90
150
In this table the data with gray blocks are recommended frequency values. A user thus
can easily choose a buzzer frequency based on the table.
(3) Conversion Rate
The ES51963 provided several conversion rates (CRs) that can be selected by external
microprocessor. The way to change conversion rate is similar to that of buzzer frequency
selection. and the CRs follow the below formula:
fosc1× F2 (C2,C1,C0)
CR =
ꢀꢀ(times / sec)
4 ×106
where,
fosc1 : ES51963 operating frequency.
CR : conversion rate.
C2, C1, C0 : provided by external microprocessor.
F2( . ) : the CR's ratio defined in the following table.
According to the formula, a user can select a conformable and reasonable conversion rate.
The values of C2, C1 and C0 are 0, 1 and 1 respectively in default. Thus the default
conversion rate is 10 times/sec with 4 MHz operating frequency. The following table lists
6
2003/9/1
CYRUSTEK [ Cyrustek corporation ]
