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宏晶科技:专业单片机 / 存储器供应商 www.MCU-Memory.com STC12C5410AD 系列 1T 8051 单片机中文指南
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;例: Fosc = 18.432MHz, Baud0 = 57600 (12T 模式)
; 1. RELOAD = 256 - INT( 18432000/57600/32/12 + 0.5)
; = 256 - INT( 0.833 + 0.5 )
; = 256 - INT( 1.333 )
; = 256 - 1
; = 255
; = 0FFH
; 2. Baud = 18432000/(256-255)/32/12
; = 48000
; 3. error = (48000 - 57600)/57600 * 100%
; = -16.66%
; 4. 误差很大, 要更换波特率或者更换晶体频率, 重新计算请见下一例
;例: Fosc = 18.432MHz, Baud0 = 9600 (12T 模式)
; 1. RELOAD = 256 - INT( 18432000/9600/32/12 + 0.5)
; = 256 - INT( 5.5 )
; = 256 - 5
; = 251
; = 0FBH
; 2. Baud = 18432000/(256-251)/32/12
; = 9600
; 3. 一目了然, 误差等于零
;例: Fosc = 2.000MHz, Baud = 4800 (1T 模式)
; 1. RELOAD = 256 - INT( 2000000/4800/32 + 0.5)
; = 256 - INT( 13.02 + 0.5 )
; = 256 - INT( 13.52 )
; = 256 - 13
; = 243
; = 0F3H
; 2. Baud = 2000000/(256-243)/32
; = 4808
; 3. error = 0.16%
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