The normal meeting format will be followed (welcome new attendees, announcements, problem/design review of the month, presentation, community project status, show and tell). This month’s presentation will be by Nick Edgington of Edgington Labs. Nick will share details of a very inexpensive line of mixed signal FPGAs (initial breakout board coming from OSH Park). Additional meeting time will be devoted to the status of the TriEmbed Community “Espressif 32 bit processor board + FPGA(s)” development board project.
With the introduction of the Raspberry Pi Pico , “Raspberry Pi” can now be thought of as a brand with two distinct product types. The Pico board features a Foundation-designed chip on a small board only needing header pins, offering an inexpensive but very powerful and versatile microcontroller suited for applications where Linux is less well suited.
With two M0+ Cortex cores, six independent banks of SRAM totaling 254KB, support for execute in place (XIP) from up to 16MB of outboard flash (2MB on the Pico board) at up to 133MHz, and support for variable clock rate and novel programmable I/O control, this is not your everyday low-end Cortex board. Below is a list of links to more details about Pico, its processor chip, firmware, software and tool chain, as well as the complete collection of related source repositories. (1/26/2021: Some host platform-specific tools are also included now. Thanks, Mike Fulbright!).
(Notes by Paul MacDougal with some light editing by Pete and Jenny Soper. A volunteer for February notes is needed.)
Problem Of The Month (P.O.T.M.)
Paul MacDougal reviewed his long history of making some kind of puzzle to give to his nieces. A last minute flash of inspiration resulted in a maze in which two "pointers" following identical mazes were modified to be two "pointers" following different mazes. This requires the pointers to be able to move relative to one another. Controlling this movement and creating compatible mazes induced development of software for creating and manipulating mazes. The "problem" this month was to suggest new features for this maze software.
Code Review Of The Month (C.R.O.T.M.)
Carl converted Paul's short python script to a class-based implementation. There was some discussion of Paul doing a sys.exit(x) from within a script that is running separate threads and how that might mess up. "FOO" vs "foo" vs "_foo" vs "__foo" conventions in Python. (And let's not forget "Foo"!)
Presentation: ESP8266 OTA by Paul MacDougal
ESP8266 supplier Espressive has done all the hard work to use Over The Air firmware/data update (OTA) in its libraries. Paul showed a simple sketch to do OTA from the Arduino IDE which is just running a python script. Multicast DNS (mDNS) is used for identifying development boards via name rather than IP address. A simple sketch to do OTA by connecting to a device using HTTP was shown. There was discussion of using ports 80 vs 8080 (really < 1024 vs > 1023). A simple sketch to do OTA by device accessing a server at a known IP address was shown and there was discussion of security (or lack thereof) of OTA programming.
