UM-TM57PA20&40_S
8 Bit Microcontroller
Advance Information
5.3.7 蜂鸣输出
TM59PA80 (TM57PA40)的蜂鸣驱动器包含有 6-BIT 的计数器和时钟分频器。它可产生
50％(占空比）的工作方波，并且其频率覆盖一个较宽的范围。使用蜂鸣输出功能，需
要设置蜂鸣使能控制位（BUZ-EN）和蜂鸣输出使能控制位（BUZ-OUT）。
Buzzer
Counter
Buzzer Data
Change
Before > After
Buzzer Data
Change
Before < After
Buzzer
Disable
Buzzer
Enable
Buffer
Reload
Buzzer
Output
BUZ-PROD [5：0] 决定输出频率。频率计算如下：
FBZ = (fOSC/2) / (Instruction Cycle Divider) / (BUZ_PROD +1)
计算输出频率 ：
CPU Clock (fosc) = 8192KHz
Instruction Cycle = fosc/2 = 8192KHz/2 = 4096KHz
Prescaler Ratio (BUZ_PSC) = 2’b11 (Instruction Cycle Divider = 32)
Period Data (BUZ_PROD) = 9
FBZ = (8192KHz/2) / 32 / (9+1) = 12.8 (KHz)
19
tenx technology, inc.
Preliminary
Rev 1.1, 2009/10/19
ETC [ ETC ]
