Top microcontroller threads on EDAboard.com – August

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PWM using Controller – I  working on one project which requires the following condition: Analog voltage and PWM on the same pin as the microcontroller. Is this possible? Currently I am using one pin of microcontroller. Read more

Sensored BLDC motor issue – I am developing a driver which is has a max current protection 20A. The motor is driving on 12V and 24V. The motor is a 3-phase BLDC motor. My driver gives motor speed as 1800 RPM at 24V, 1.3A without load, and 900 RPM at 12V, 0.9A without load. I have checked the other drivers which have dedicated IC in the circuitry for BLDC motors. They are giving the following speeds,

2000 RPM at 24V , 1.5A current
1100 RPM at 12V, 1.1A current

My project is to change those dedicated ICs with a microcontroller. I have implemented and its working fine. All functionalities are working fine. But the project is not acceptable because of speed characteristics. Read more

Ethernet communication using microcontroller – I want to make a device that will send a link to a local host via LAN/Ethernet. The host PC is connected with the device via LAN cables, switches/routers, and there will be over 100+ same devices which are doing the same. In this case how the system should be arranged?  Does it need to give each device a IP address for each? And how these devices will send the data to the main PC or local host? Read more

Problem on UART PIC16F628A Tx – Rx – I’m having a problem adding a button. There is no an error (except I place UART2_Read), but I can’t add more buttons on PORTA.F1 (Tx) and Led PORTB.F4 (Rx). Read more

Two keys (0 or 4) pressed at same time – What happens when in color key 0 and key 4 are pressed and held. What display behavior will be affected? Read more

Current protection issue in BLDC motor – I am developing BLDC motor driver with 24V ,20A current.  Suppose, the motor is at full load and POT (Throttle) is at maximum and then the motor is trying to start and somebody picks rotor by hand then the motor stops. It should reach 20 A and then it should stop as 20A set as current protection range. But it is stopping at 1 A or 2 A of current. Read more

5 µsec delay using PIC12f675 not working – I am using a PIC12f675 with a 20 Mhz clock and a PIC12f675 with 20 Mhz clock I want to generate a 5 µs delay. I calculate by using this formula:
Pic input frequency= Fosc / 4= 20 Mhz / 4 = 5 Mhz
Prescaler = 1:4
Tick Counter frequency = Prescaler/5 Mhz = 4 / 5 Mhz = 0.8 μs
Delay required =5 μs
Delay required = Timer Count * Tick Counter frequency
by using this formula timer count is 249. Read more

dsPIC33f internal Flash as EEPROM – For my application a 16-bit  dsPIC33FJ64GS606 microcontroller. The controller doesn have an EEPROM option. I found an option to use Program memory as for EEPROM from the Microchip website. I got Project file but it cannot compile it. Read more

Concatenating bytes into a 32-bit word – I’m comparing two methods for concatenating received UART bytes into 32-bit words. Method #0 uses unions Method #1 – uses shifting Although both of the above work, I’d like to know which one do you find better to use and why? Read more

How to implement a lookup table in C programming? In one of my applications, I need to use a lookup table in C. I need to pick the data depending on two variable parameters —temperature and pressure. For example, if temp=0 and pressure=750, then I have to pick 14.37.and so on. Please see the attached table. Read more