參數(shù)資料
型號(hào): MC80C52XXX-25/883
廠商: TEMIC SEMICONDUCTORS
元件分類: 微控制器/微處理器
英文描述: 8-BIT, MROM, 25 MHz, MICROCONTROLLER, CDIP40
文件頁(yè)數(shù): 77/83頁(yè)
文件大?。?/td> 8336K
代理商: MC80C52XXX-25/883
89
7707F–AVR–11/10
AT90USB82/162
Each half period of the external clock applied must be longer than one system clock cycle to
ensure correct sampling. The external clock must be guaranteed to have less than half the sys-
tem clock frequency (f
ExtClk < fclk_I/O/2) given a 50/50% duty cycle. Since the edge detector uses
sampling, the maximum frequency of an external clock it can detect is half the sampling fre-
quency (Nyquist sampling theorem). However, due to variation of the system clock frequency
and duty cycle caused by Oscillator source (crystal, resonator, and capacitors) tolerances, it is
recommended that maximum frequency of an external clock source is less than f
clk_I/O/2.5.
An external clock source can not be prescaled.
Figure 13-2. Prescaler for synchronous Timer/Counters
13.0.4
General Timer/Counter Control Register – GTCCR
Bit 7 – TSM: Timer/Counter Synchronization Mode
Writing the TSM bit to one activates the Timer/Counter Synchronization mode. In this mode, the
value that is written to the PSRASY and PSRSYNC bits is kept, hence keeping the correspond-
ing prescaler reset signals asserted. This ensures that the corresponding Timer/Counters are
halted and can be configured to the same value without the risk of one of them advancing during
configuration. When the TSM bit is written to zero, the PSRASY and PSRSYNC bits are cleared
by hardware, and the Timer/Counters start counting simultaneously.
Bit 0 – PSRSYNC: Prescaler Reset for Synchronous Timer/Counters
When this bit is one, Timer/Counter0 and Timer/Counter1, Timer/Counter3, Timer/Counter4 and
Timer/Counter5 prescaler will be Reset. This bit is normally cleared immediately by hardware,
except if the TSM bit is set. Note that Timer/Counter0 and Timer/Counter1 share the same pres-
caler and a reset of this prescaler will affect all timers.
PSR10
Clear
Tn
clk
I/O
Synchronization
TIMER/COUNTERn CLOCK SOURCE
clk
Tn
TIMER/COUNTERn CLOCK SOURCE
clk
Tn
CSn0
CSn1
CSn2
CSn0
CSn1
CSn2
Bit
7
6
5
4
3
2
1
0
TSM
-
PSRSY
NC
GTCCR
Read/Write
R/W
R
R/W
Initial Value
0
相關(guān)PDF資料
PDF描述
MQ80C52EXXX-25:R 8-BIT, MROM, 25 MHz, MICROCONTROLLER, CQFP44
MR80C32-12P883 8-BIT, 12 MHz, MICROCONTROLLER, CQCC44
MC80C32-36SHXXX 8-BIT, 36 MHz, MICROCONTROLLER, CDIP40
MQ80C32-20:RD 8-BIT, 20 MHz, MICROCONTROLLER, CQFP44
MQ80C52TXXX-16SHXXX:RD 8-BIT, MROM, 16 MHz, MICROCONTROLLER, CQFP44
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MC80D21000G 制造商:COR 功能描述:RN
MC80F0104 制造商:未知廠家 制造商全稱:未知廠家 功能描述:8-BIT SINGLE-CHIP MICROCONTROLLERS
MC80F0104B 制造商:未知廠家 制造商全稱:未知廠家 功能描述:8-BIT SINGLE-CHIP MICROCONTROLLERS
MC80F0104D 制造商:未知廠家 制造商全稱:未知廠家 功能描述:8-BIT SINGLE-CHIP MICROCONTROLLERS
MC80F0204 制造商:未知廠家 制造商全稱:未知廠家 功能描述:8-BIT SINGLE-CHIP MICROCONTROLLERS