Dan Drown

Debian for STM32MP1

I bought a STM32MP1 dev board [https://www.st.com/en/evaluation-tools/stm32mp157a-dk1.html] because it has a gigabit NIC with 1588 PTP timestamps as well as hardware timers that can timestamp PPS events without interrupt latency and jitter. I am hoping that it will both be better than the

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

NTS part 2

Part 1: Packet format of Network Time Security [https://blog.dan.drown.org/ntp-security/] I wanted to measure the overhead that NTS adds to NTP. To give a rough estimate, I modified the benchmark program included in libaes_siv [https://github.com/dfoxfranke/libaes_siv] to use similar parameters as

NTP security (NTS)

I've been hearing about Network Time Security (NTS) being in development for awhile now. With Cloudflare's release of a public NTS [https://blog.cloudflare.com/secure-time/] service, I wanted to take a closer look at the protocol and test it out. The current NTS draft [https:

Embedded NTP client/NTP interleaved mode, part 2

Hardware transmit timestamps added to NTP client.

Embedded NTP client/NTP interleaved mode

NTP client with hardware timestamps

APU2 NTP server

I bought an apu2c0. I believe it will make a better NTP server than my other NTP servers.

RK3328 based NTP server

I got a ROC-RK3328-CC [https://libre.computer/products/boards/roc-rk3328-cc/] SBC because it has true gigabit ethernet, emmc, and USB3. These are all better I/O options than the latest Raspberry Pi 3 B+. I put a SATA hard drive in a USB3 adapter and connected it. The SBC froze

TL-MR3020 NTP server, part 2

Part 1 [https://blog.dan.drown.org/mr3020-ntp-server/] was about the hardware, now for the software Step 1: pps-gpio-poll package This architecture doesn't support device tree yet, so it has a special pps driver. The repo for the driver package is at https://github.com/mlichvar/openwrt-pps-gpio-poll I

TL-MR3020 NTP server

I have a small travel router that I no longer use, and I wanted to turn it into a NTP server. The hardware is pretty well documented here: https://openwrt.org/toh/tp-link/tl-mr3020 For the PPS signal input into the router, I need a GPIO [https://en.wikipedia.org/