Ten Daily Electronic Common Sense-Section 33

How does the ARM processor hardware respond to the following process when an abort occurs (assuming the interrupt is not masked)?

• When an abnormal interrupt occurs, the ARM processor hardware will automatically respond to the following process (assuming that the interrupt is not masked):
  1. Set the register LR as the return address.
  2. Save the current program status register. Method: Save the CPSR content of the previous mode to the SPSR register corresponding to the abnormal interrupt.
  3. Turn off the interrupt. Disable IRQ interrupts in CPSR, or disable IRQ and FIQ interrupts at the same time, to prevent the CPU from responding to the same type of interrupt.
  4. Set the PC value to the entry address of the abnormal interrupt. When IRQ interrupt occurs, PC=0x0000 0018; When FIQ interrupt occurs, PC=Ox0000 001C.
• The above process is done automatically by the ARM processor hardware without user intervention.

Compared with amplitude modulation, what are the advantages of FM?

• Good anti-interference when receiving;
• High power utilization rate of the transmitter (power is limited by the ability of the transmitting tube);
• The quality of the transmitted signal is good, and the dynamic range is large;
• The large dynamic range in ASK technology is avoided Most noise problems can ignore voltage spikes.
• Therefore, FM is often used in local voice broadcasting in daily life, accompanying sound in TV broadcasting, ultra-high frequency wireless telephone communication, data communication and telephone communication in data communication, etc. In data communication, the application of 2FSK is very extensive, and the International Telecommunication Union (ITU) recommends using the 2FSK system when the data rate is lower than 1 200b/s. 2FSK can adopt non-coherent receiving method, and it is not necessary to use the phase information of the signal when receiving, so it is especially suitable for applications in fading channels/parametric channels (such as short-wave radio channels), which will cause random jitter and fluctuation of the phase and amplitude of the signal.

What are the traditional BER testers?

A traditional BERT consists of two parts: (1) a pattern generator (2) an error receiver

What are the types of sensors for electronically controlled automatic air conditioning systems?

1. In-vehicle temperature sensor
2. Out-of-vehicle temperature sensor
3. Evaporator temperature sensor
4. Sunlight sensor
5. Coolant flow sensor
6. Compressor lock sensor
7. Smoke density sensor
8. Humidity Sensor

Which five subsystems are the power management system also divided into?

1. The backlight of a monochrome display can be composed of different colors of light, generally using 4 LEDs of the same color.
2. Similar to the configuration of the display board, the keyboard board is also illuminated by LEDs, usually using 8 white or blue LEDs.
3. The vast majority of electronic components in mobile phones are concentrated on the main board, including baseband DSP, application microcontroller, transceiver and analog interface.
4. The power management system in the battery pack mainly includes lithium-ion battery protection circuit, power measurement IC and MOSFET.
5. The AC adapter should ensure high efficiency under the condition of small load and full load.

What are the sensors used in the engine control system that are the core of the entire automotive sensor?

Temperature sensors, pressure sensors, position and speed sensors, flow sensors, gas concentration sensors and detonation sensors, etc.

What is a collision sensor?

Collision sensors are generally used in airbag systems and are the main signal input devices in airbag systems.

What are the general steps to resolve the redundancy method?

1. Model design.
2. Design residuals related to sensor failure.
3. Carry out statistical tests and logical analysis.

What are biometrics technologies?

• Speech recognition
• Fingerprint identification
• Face recognition

What are the characteristics of the Spartan-3A series?

Its main features are as follows: Adopt 90nm process, the density is up to 74880 logic cells; The operating clock range is 5 ~ 320MHz; The leading connection function platform has the most extensive I/O standard (26 types, including new TMDS and PPDS) support; The industry’s first powerful anti-cloning security feature realized by unique Device DNA serial number; 5 devices with up to l. 4M of system gates and 502 I/Os; flexible power management.