W921E400A Datasheet, PDF (22/53 Pages) Winbond – 4-BIT MICROCONTROLLER

W921E400A/W921C400
6.8 Beep Tone Generator
There are four kinds of frequency that can output from the BTG pin that works as beep tone
generator. The BTG pin can output the special frequency -- 2 KHz, 1 KHz, 630 Hz or 520 Hz, and the
correct output frequency is decided by the OSCCTR register (address = 013H) and BTGR register
(address = 03FH) as shown below:
BTGR REG: (ADDRESS = 03FH, default data = 0H)
b3
b2
b1
b0
Reserved
b1 b0 Output-Freq.
00
2 KHz
01
1 KHz
10
630 Hz
11
520 Hz
0: Beep Tone Generator disable
(BTG pin keep in high state)
1: Beep Tone Generator enable
If the Beep Tone Generator is disabled by setting bit3 of the BTGR register to zero or after power on
reset, the BTG output pin will remain in high state.
6.9 Comparator
ANI3
ANI2
ANI1
ANI0
ANIMUX
Register
Vrang = 1.5 V or (2/3)VDD
DACTL.2
8bit D/A Converter
Vani
COMPTR.1
Vref
Vpos
Vneg
COMPTR.2
DAMSB 4-bit
Register
DALSB 4-bit
Register
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