Topic

USB

A collection of 6 issues

ch32v307 dev board, part 4

Next, I will cover connecting a GPS module to a NTP server over USB. This is part of a series on the ch32v307 dev board Previous project I previously setup PPS over USB using a USB Full-Speed (12Mbit) stm32f103 device. One of the limitations of that device is USB Full-Speed

2 button keyboard

I wanted a simple keyboard with play and pause media keys to make it convenient to control my music. To handle the USB, I used a STM32F103 based "blue pill" board because they're cheap and easy to work with. First I put together a simple design

GPS module measurements, part 2

After the previous tests [https://blog.dan.drown.org/gps-module-measurements/], I ordered another GPS antenna to improve the signal conditions. They're just the cheap puck style antennas with SMA connectors ($10 on Amazon), and I've put them on my windowsill. There's something wrong with

GPS module measurements

Starting point I got a u-blox NEO-6M and I wanted to compare it to my NS-T. Since I don't have a frequency counter, I decided to try creating one myself. The hardware I have on hand is a 72MHz STM32 devboard. I used the input capture hardware on

PPS over USB

Goal For keeping your system clock on time, you can't beat the Pulse Per Second (PPS) signals available from $10 GPS modules. They typically have better than 100 nanosecond accuracy [https://blog.dan.drown.org/gps-module-measurements-part-3/]. GPIO PPS is one of the best ways to get that timing

Navspark UART/USB bridge

I created a program on the Navspark to send characters at 150 microsecond intervals and then received them on a PC. Below is a histogram of how long it took between characters: The red boxes are how long it took for the UART/USB bridge to send one character in