5 votes
Accepted

Is it possible to read a USB port directly?

No, at least not in any remotely modern version of Windows. Accessing hardware directly requires kernel privilege level, which ordinary application programs don't have. Think about it. It has to be ...
Olin Lathrop's user avatar
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4 votes

How to transition from battery to USB in a microcontroller?

There are two possible options based on the limited infomation you have provided Consider storing data in Non-Volatile Memory. Use a LDO such as TPS73633 that can support wide input voltage range ...
Mahendra Gunawardena's user avatar
4 votes

Is it possible to read a USB port directly?

It assumed that this question is a continuation from How to transition from battery to USB in a microcontroller?. It is also assumed that your goal is to collect data using a PIC micro controller and ...
Mahendra Gunawardena's user avatar
3 votes

Preventing a DC motor from stalling

Considering that this is a class project, depending on what you use to control the DC motor, you might be able to use current limiting. The technique is called current sensing. When a DC motor is ...
NMech's user avatar
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3 votes
Accepted

Send sensor signals to WiFi network

I would keep the sensors passive as transponders to a house wide rfid radar scanner. Changes in the sensor would change the code on the rfid of the sensor, thus reflecting back a different ...
0tyranny0poverty's user avatar
2 votes
Accepted

What is the advantage of using GPIO pins as sinks instead of sources?

I think the reason is if the GPIO is used the micro is starved of power. In the method described 3.3V is the power source. So the micro is not starved of power. If the 3.3V was provided by the GPIO ...
user1586's user avatar
  • 674
2 votes
Accepted

Tuning PID Controller

There are two answers here. First answer is the theoretical one. It doesn't matter what static power you apply. You could apply any number. The reason is that the plot of y(t) that you end up drawing ...
Daniel K's user avatar
  • 2,646
2 votes

How to resolve Keil uVision 5.0 compilation errors?

On Keil uVision goto Project > Manage > Run-Time Environment. You will get a screen like the following. Your device is not properly configure as indicated by the Red box. Click on the Device + to ...
Mahendra Gunawardena's user avatar
2 votes

Send sensor signals to WiFi network

I think you won't get this done without some kind of processor and customized firmware to convert the sensor signal to a digital signal for WiFi transmisson. The dongle is a good idea, but it provides ...
bunto1's user avatar
  • 151
2 votes
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How to select a micro controller for a low power application?

The critical parameters depends on the application. Beside Low Power, other critical parameters need to be considered. These may include code size, serial communication ports etc. Below is analysis ...
Mahendra Gunawardena's user avatar
2 votes

Why we use GPIO for embedded systems?

GPIO stands for General Purpose Input Output. Lets assume you want to generate a pulse at pin 39 as in the below image. So when you wire the pulse to pin 39 the underline software will generate the ...
Mahendra Gunawardena's user avatar
2 votes
Accepted

Preventing a DC motor from stalling

When you bump the plate on a thread off the edge, the plate tilts, inertia of the motor drives the plate to a larger angle. Deformed plastic grips much stronger than what motor can move. To avoid this ...
Surprised Seagull's user avatar
2 votes
Accepted

Can the Processor Cores on SSDs be Used for General Computation?

Yes, but if you have to ask, no. SSD controllers run firmware contained in flash memory: it is the same kind of memory used for the SSD. If you know how to re-flash the controller, and know what i/o ...
david's user avatar
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1 vote

Multicurrency Ultraviolet counterfeit scanner detection machine

Not all currencies have ultraviolet features. Of those that do, the features vary. Any ultraviolet features are determined by the issuing authority and are also influenced by the material the ...
Fred's user avatar
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1 vote

Embedded C Programming

This response is based on RX130 Capacitive touch development board as shown below IDE: e2Stuido v7.5 and above Toolchain: Renesas RXC toolchain Board: RX130 Capacitive touch development board MCU: ...
Mahendra Gunawardena's user avatar
1 vote

Conversion from LSB to mg not making sense for accelerometer

I couldn't add a comment (new to the forum) so posting in the answer section. Bosch has since acknowledged this to be an error and updated the datasheet's errata. They have added a 3/2 factor to the ...
Neelabh Mam's user avatar
1 vote

What is this device?

It looks like the devkit associated with the NodeMCU community. If you turn it around with the metal portion facing away from you it should say something like "devkit v1.x". It's a developer board ...
budekatude's user avatar
1 vote
Accepted

What is this device?

There should be writing on the top (metal) portion and/or some silk screening on the bottom. Either an ESP32 or (more likely) an ESP8266. That should give you enough info to get started...
BobT's user avatar
  • 248
1 vote
Accepted

DLX assembly synthax

Basically, "Rn" means "the contents of register n" and "(Rn)" means the "data in the memory location whose address is in register Rn". For memory access, you can also add a constant to (Rn), so 4(R8)...
alephzero's user avatar
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1 vote

RTC interface with PIC16F877A

Ok firstly calm down, everything has an answer. you say you read and write data from real time counter by I2C debugger but can not by microcontroller; MCU stands between LCD and RTC right? and there ...
user12297's user avatar
1 vote

Send sensor signals to WiFi network

The cheapest option for you to consider would be to use Esp8266 modules. They technically cost 1 USD. You can import a bulk (lot) order from aliexpress to make it cheaper. For you command centre you ...
Sanketh Rajendra's user avatar
1 vote

How to measure signal period with Arduino?

I'd comment instead, but I don't have the rep so I'll have to answer. By attaching an interrupt to the rising edge of your signal you can increment a counter. You read the counter every X ...
Michael's user avatar
  • 51
1 vote

Transistor choices for switching high speed data communication lines

You don't want to physically interrupt USB data lines. These have controlled impedances, are bi-directional, and differential. These issues makes "switching" the lines difficult. In addition, DC ...
Olin Lathrop's user avatar
  • 11.4k
1 vote

What is the advantage of using GPIO pins as sinks instead of sources?

Early TTL outputs (those typical of 74xx00 series logic gates) were capable of sinking (creating a current path to ground) more current than they could source (creating a current path to VCC). If you ...
Entrepreneur's user avatar
1 vote

Bread board for STM32

If you don't want to solder wires to the microcontroller contacts looking into STM32 expansion boards. They look something like the following: The above one is called STM32 discovery shield. You can ...
Mahendra Gunawardena's user avatar
1 vote

Bread board for STM32

Based on the image I believe that the GPIO pins are already mapped to 0.1" (2.54mm) male connector pins. If my assumption is correct you have few options Use 0.100" (2.54 mm) Female Header such as ...
user1586's user avatar
  • 674
1 vote

Why not only GSM (3G/4G/..)? Why do we need Bluetooth, Wifi,etc...?

Several reasons but mostly bandwidth and speed. It makes sense to keep all communication channels as short and local as possible. This reduces likelihood of interference, channel contention and cost. ...
Transistor's user avatar
  • 10.6k
1 vote

Why not only GSM (3G/4G/..)? Why do we need Bluetooth, Wifi,etc...?

Several reasons. Firstly: They're designed for different purposes. It's basically the same reason individual power tools are usually better than all-in-ones. Sacrafices in one aspect are used for ...
Jodes's user avatar
  • 1,304
1 vote

How can electrical noise be isolated in an Embedded System?

With a 20 ms pulse width you really should not be using interrupts directly. The usual thing is to have some timer generating periodic interrupts at maybe 250Hz or so, then if on two consecutive ...
Dan Mills's user avatar
  • 251
1 vote

What are the pros and cons of using Zibgee over BLE or vice versa for IOT application?

The present technology is all about IOT i. e with millions of devices connected over internet. Zigbee and BLE are two types of wireless communication which is used for interacting between two or more ...
sristi bali's user avatar

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