參數(shù)資料
型號: MR80C52EXXX-25:RD
廠商: ATMEL CORP
元件分類: 微控制器/微處理器
英文描述: 8-BIT, MROM, 25 MHz, MICROCONTROLLER, CQCC44
封裝: LCC-44
文件頁數(shù): 141/176頁
文件大?。?/td> 2962K
67
2535J–AVR–08/10
ATtiny13
The Timer/Counter Overflow Flag (TOV0) is set each time the counter reaches BOTTOM. The
Interrupt Flag can be used to generate an interrupt each time the counter reaches the BOTTOM
value.
In phase correct PWM mode, the compare unit allows generation of PWM waveforms on the
OC0x pins. Setting the COM0x1:0 bits to two will produce a non-inverted PWM. An inverted
PWM output can be generated by setting the COM0x1:0 to three: Setting the COM0A0 bits to
one allows the OC0A pin to toggle on Compare Matches if the WGM02 bit is set. This option is
not available for the OC0B pin (See Table 11-4 on page 70). The actual OC0x value will only be
visible on the port pin if the data direction for the port pin is set as output. The PWM waveform is
generated by clearing (or setting) the OC0x Register at the Compare Match between OCR0x
and TCNT0 when the counter increments, and setting (or clearing) the OC0x Register at Com-
pare Match between OCR0x and TCNT0 when the counter decrements. The PWM frequency for
the output when using phase correct PWM can be calculated by the following equation:
The N variable represents the prescale factor (1, 8, 64, 256, or 1024).
The extreme values for the OCR0A Register represent special cases when generating a PWM
waveform output in the phase correct PWM mode. If the OCR0A is set equal to BOTTOM, the
output will be continuously low and if set equal to MAX the output will be continuously high for
non-inverted PWM mode. For inverted PWM the output will have the opposite logic values.
At the very start of period 2 in Figure 11-7 on page 66 OCn has a transition from high to low
even though there is no Compare Match. The point of this transition is to guarantee symmetry
around BOTTOM. There are two cases that give a transition without Compare Match.
OCR0A changes its value from MAX, like in Figure 11-7 on page 66. When the OCR0A value
is MAX the OCn pin value is the same as the result of a down-counting Compare Match. To
ensure symmetry around BOTTOM the OCn value at MAX must correspond to the result of
an up-counting Compare Match.
The timer starts counting from a value higher than the one in OCR0A, and for that reason
misses the Compare Match and hence the OCn change that would have happened on the
way up.
11.8 Timer/Counter Timing Diagrams
The Timer/Counter is a synchronous design and the timer clock (clkT0) is therefore shown as a
clock enable signal in the following figures. The figures include information on when Interrupt
Flags are set. Figure 11-8 on page 68 contains timing data for basic Timer/Counter operation.
The figure shows the count sequence close to the MAX value in all modes other than phase cor-
rect PWM mode.
fOCnxPCPWM
fclk_I/O
N510
------------------
=
相關(guān)PDF資料
PDF描述
MIP7365-450F17I 64-BIT, 450 MHz, MICROPROCESSOR, CQFP208
MIP7365-450B1M 64-BIT, 450 MHz, MICROPROCESSOR, PBGA256
MK1574-01BSITR 1574 SERIES, PLL BASED CLOCK DRIVER, 4 TRUE OUTPUT(S), 0 INVERTED OUTPUT(S), PDSO16
MK1574-01ASTR 1574 SERIES, PLL BASED CLOCK DRIVER, 4 TRUE OUTPUT(S), 0 INVERTED OUTPUT(S), PDSO16
MK1575-01GLFTR 1575 SERIES, PLL BASED CLOCK DRIVER, 2 TRUE OUTPUT(S), 0 INVERTED OUTPUT(S), PDSO16
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MR80C86 制造商:INTERSIL 制造商全稱:Intersil Corporation 功能描述:CMOS 16-Bit Microprocessor
MR80C86/B 制造商:Rochester Electronics LLC 功能描述:- Bulk 制造商:Harris Corporation 功能描述:Microprocessor, 16 Bit, 44 Pin, Ceramic, LCC
MR80C86-2 制造商:INTERSIL 制造商全稱:Intersil Corporation 功能描述:CMOS 16-Bit Microprocessor
MR80C86-2/883 制造商:Rochester Electronics LLC 功能描述:- Bulk
MR80C86-2/B 制造商:Intersil Corporation 功能描述:MPU 80C86 16BIT CMOS 8MHZ 44PLCC - Rail/Tube