str912fa STMicroelectronics, str912fa Datasheet - Page 29

• Manufacturer Part Number: str912fa
• Description: Arm966e-s? 16/32-bit Flash Mcu With Ethernet, Usb, Can, Ac Motor Control, 4 Timers, Adc, Rtc, Dma
• Manufacturer: STMicroelectronics

STR91xFA
2.24
2.24.1 DMA
2.25
A/D converter (ADC) with DMA
The STR91xFA provides an eight-channel, 10-bit successive approximation analog-to-digital
converter. The ADC input pins are multiplexed with other functions on Port 4 as shown in
Table
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A programmable DMA channel may be assigned by CPU firmware to service each ADC
conversion result for fast DMA single-transfer.
Standard timers (TIM) with DMA
The STR91xFA has four independent, free-running 16-bit timer/counter modules designated
TIM0, TIM1, TIM2, and TIM3. Each general purpose timer/counter can be configured by
firmware for a variety of tasks including; pulse width and frequency measurement (input
capture), generation of waveforms (output compare and PWM), event counting, delay timing,
and up/down counting.
Each of the four timer units have the following features:
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Fast conversion time, as low as 0.7 usec
Accuracy. Integral and differential non-linearity are typically within 4 conversion counts.
0 to 3.6V input range. External reference voltage input pin (AVREF) available on 128-pin
packages for better accuracy on low-voltage inputs. See
restrictions to the relative voltage levels of VDDQ, AVDD, AVREF, and AVREF_AVDD.
CPU Firmware may convert one ADC input channel at a time, or it has the option to set the
ADC to automatically scan and convert all eight ADC input channels sequentially before
signalling an end-of-conversion
Automatic continuous conversion mode is available for any number of designated ADC
input channels
Analog watchdog mode provides automatic monitoring of any ADC input, comparing it
against two programmable voltage threshold values. The ADC unit will set a flag or it will
interrupt the CPU if the input voltage rises above the higher threshold, or drops below the
lower threshold.
The ADC unit goes to stand-by mode (very low-current consumption) after any reset event.
CPU firmware may also command the ADC unit to stand-by mode at any time.
ADC conversion can be started or triggered by software command as well as triggers from
Timer/Counter (TIM), Motor Controller and input from external pin.
16-bit free running timer/counter
Internal timer/counter clock source from a programmable 8-bit prescale of the CCU PCLK
clock output
Optional external timer/counter clock source from pin P2.4 shared by TIM0/TIM1, and pin
P2.5 shared by TIM2/TIM3. Frequency of these external clocks must be at least 4 times
less the frequency of the internal CCU PCLK clock output.
Two dedicated 16-bit Input Capture registers for measuring up to two input signals. Input
Capture has programmable selection of input signal edge detection
Two dedicated 16-bit Output Compare registers for generation up to two output signals
PWM output generation with 16-bit resolution of both pulse width and frequency
5. Following are the major ADC features:
Table 7: Operating
Functional overview
conditions, for
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