I recently decided to update the Polar Coaster project. The primary reason was to update the controller to use Grbl_ESP32 firmware. I also thought I could make it smaller, lighter and remove a little cost.
The old controller was not custom made and just sort of tacked onto the back. This increased the size and didn’t look very good. It had a Bluetooth module, but you still had to stream the gcode. You could use an Android app, but that was still a little awkward.
The controller runs Grbl_ESP32. This was recently updated to include pen machine features. This allows precise control and calibration of the pen servo. You can control the speed, timing and endpoints of the servo travel.
Thorough items on a linear regulator datasheet provides valuable details about its proper usage discussed in this App note from ROHM semiconductor. Link here (PDF)
A linear regulator data sheet includes a specifications table that lists output voltage values and precision. Besides, very important information such as maximum ratings, operating conditions and characteristic graphs are described in the table.
App note from ROHM semiconductor on combining LDOs for higher load capacity. Link here (PDF)
When you want to increase the output current capacity of an LDO, or when the power dissipation of a single LDO is insufficient, you might think of connecting LDOs in parallel if you need to disperse the dissipation using two LDOs. This application note provides some hints on how to connect LDOs in parallel.
I’ve been playing with a multislope ADC design. Multislope ADC are often used in high end multimeters, and as I have a mild obsession with 8.5 digit multimeters, I wanted to try making a multislope ADC.
We initially developed this USB atmospheric pressure monitor to study some operating characteristics of Bosch BMP180 sensor. BMP180 is low cost sensor to measuring barometric pressure and temperature. According to the data sheet this sensor can use to measure pressure ranging between 300hPa to 1100hPa. This sensor is introduced couple of years back but still it is popular due to lower cost and simplicity of it’s interface.
App note from STMicroelectronics about interfacing STM32 legacy USB 2.0 to USB Type-C. Link here (PDF)
This application note is a guideline to introduce this USB Type-C connector onto platform to replace legacy USB2.0 connectors. It introduces some basis of the two new standards USB Type-C™ and the USB Power Delivery.
Extend memories by using external high speed memories interfaced to Quad-SPI modules on STM32 micros, app note from STMicroelectronics. Link here (PDF)
This application note describes the Quad-SPI interface on the STM32 microcontrollers and explains how to use the module to configure, program, and read external Quad-SPI memories. It describes some typical use cases to use Quad-SPI interface based on some software examples from the STM32Cube firmware package and from the STM32F7 application notes.
This is the first of what I expect to become a multi-part article series on the CAN bus. I’d like to describe the features of CAN which I find particularly elegant and useful, and will introduce a simple driver I have implemented for it as part of the JeeH library. Along the way, I’ll try to illustrate its use with a variety of small demo apps, running on either a Blue Pill (i.e. F103), or one of the STM32F4 µC families.
After a 4 year run the dashcam on my car stopped working: a fault seems to have developed in the power system. It was mounted to the window by what I thought was just a simple mechanical mount… on further analysis it became clear that the GPS receiver was part of the mount (makes sense as the user normally glues this part to the windscreen).
This is real-time clock based automatic LED lamp which we originally designed to use as night light. This lamp can programmed to turn on and off at the specific time of the day. For example, it can program to turn on at 6 PM on each day and to turn off at 4 AM next day.
The core component of this project is PIC16F883 MCU and it’s firmware is developed using MikroC Pro for PIC. We select this MCU because of it’s 7 KB flash memory, I2C, UART, E2PROM and built-in 8-bit and 16-bit timers.