W741E20X Datasheet, PDF (13/84 Pages) Winbond – 4-BIT FLASH MICROCONTROLLER

Preliminary W741E20X
For example, when FT equals 32768 Hz, depending on the preset value of TM1, the MFP pin will
output a single tone signal in the tone frequency range from 64 Hz to 16384 Hz. The relation between
the tone frequency and the preset value of TM1 is shown in the table below.
C
C#
TD
D#
OE
F
N F#
G
E G#
A
A#
B
Tone
frequency
130.81
138.59
146.83
155.56
164.81
174.61
185.00
196.00
207.65
220.00
233.08
246.94
3
TM1 preset value &
MFP frequency
7CH
131.07
75H
138.84
6FH
146.28
68H
156.03
62H
165.49
5DH
174.30
58H
184.09
53H
195.04
4EH
207.39
49H
221.40
45H
234.05
41H
248.24
Tone
frequency
261.63
277.18
293.66
311.13
329.63
349.23
369.99
392.00
415.30
440.00
466.16
493.88
4
TM1 preset value &
MFP frequency
3EH
260.06
3AH
277.69
37H
292.57
34H
309.13
31H
327.68
2EH
372.36
2BH
390.09
29H
420.10
26H
443.81
24H
442.81
22H
468.11
20H
496.48
Tone
frequency
523.25
554.37
587.33
622.25
659.26
698.46
739.99
783.99
830.61
880.00
932.23
987.77
5
TM1 preset value &
MFP frequency
1EH
528.51
1CH
564.96
1BH
585.14
19H
630.15
18H
655.36
16H
712.34
15H
744.72
14H
780.19
13H
819.20
12H
862.84
11H
910.22
10H
963.76
Note: Central tone is A4 (440 Hz).
Mode Register 0 (MR0)
Mode Register 0 is organized as a 4-bit binary register (MR0.0 to MR0.3). MR0 can be used to control
the operation of Timer 0. The bit descriptions are as follows:
3210
MR0 W
W
Note: W means write only.
Bit 0 = 0 The fundamental frequency of Timer 0 is FOSC/4.
= 1 The fundamental frequency of Timer 0 is FOSC/1024.
Bit 1 & Bit 2 are reserved
Bit 3 = 0 Timer 0 stops down-counting.
= 1 Timer 0 starts down-counting.
- 13 -
Publication Release Date: March 1998
Revision A1