What's in a hub?
The restart of the JET project is progressing nicely. This week’s episode is about installing a first version as a basic-yet-functional new core system and describing / documenting some of the central...
View ArticleLet's talk about the 'N' in WSNs
The acronym “WSN” stands for Wireless Sensor Network. Ok sure, we all have one or more wireless sensor nodes, JeeNodes or whatever, and they probably work nicely. But how do we manage them? What about...
View ArticleDay-to-day JET practicalities
Here’s a “JET” engine, for your amusement: This week, I’m going to go into the practical aspects of the JET project: for production, i.e. the always-running hub + MQTT server, and for development, i.e....
View ArticleThe PDP-8, half a century ago
In 1965, computing history was made when DEC introduced a new computer, called the PDP-8. It was the start of a long series of incrementally improved models, later to be followed by the even more...
View ArticleDive into Forth
In 1965, computing history was made when DEC introduced a new computer, called the PDP-8 - oh, wait, that was last week’s post. But it applies here too: 1968 was the year when Charles Moore invented...
View ArticleDive into Forth, part 2
Switching to Mecrisp Forth implies starting from scratch as far as low-level access is concerned. There’s no C “runtime library” to fall back to, everything will have to be implemented in Forth. This...
View ArticleDive into Forth, part 3
The Forth adventure continues… this is part 3 of a series about Mecrisp Forth on ARM STM32F103 µCs - an amazing environment for interactively trying out the hardware in this well-established chip...
View ArticleWhere is this going?
The last three weeks have been a deep dive into the programming language Forth on STM32 µCs. Results so far have been very encouraging, in terms of using Forth for programming ARM µCs in general. But...
View ArticleAnd so Forth...
This week’s episode will be a short one, as I try to push though some issues and prepare for greater things to come. First, a little progress report on getting USB going in Mecrisp Forth on the...
View ArticleFrom Zero To Wireless
This week, I’m going to set up a wireless node from scratch, using an STM32F103 board, RFM69 radio module, serial USB interface board, and very simple software: The result is a node with all the...
View ArticleAnalog Explorations
There are many projects going on in parallel here at JeeLabs at the moment. One reason is that I’m simply always chasing new butterflies… ehm, I mean areas of technology. Another one is that sometimes...
View ArticleReal op-amps
Operational amplifiers are the work horses of analog. The standard notation for it is: There are lots of low-cost op-amps available these days. Easy-to-use 8- or 14-pin chips, with 1, 2, or 4 op-amps...
View ArticleWater damage
We recently had a small water leak in the kitchen - leading to a 3-hour server outage for JeeLabs. Very early in the morning, so very few people will have noticed it - other than an ever-vigilant...
View ArticleGoing 32-bit, at last
Given last week’s mishap, and the resulting damage to the main metering JeeNode, it’s time to start creating a new setup. While I’m at it, I’ll throw a few new measurements into the mix and will also...
View ArticleUpstairs, downstairs
It turns out that tinkering and development is hard when the signals to be measured are located far from my desk and electronics workbench. The meter cabinet is located downstairs next to the front...
View ArticleThis week's potpourri
This week will be a hodgepodge of topics which I’ve been working on recently: a hardware interaction which kept me really puzzled for quite some time, a delightful excursion into the deeper innards of...
View ArticleWorking on JEM
The JeeLabs Energy Monitor prototype is progressing nicely - once I figured out that I had my numbering of the Arduino analog pins 0..5 reversed… doh! Here is what’s on the menu for this week: Tracking...
View ArticleTying up several loose ends
This week is yet another mixed bag of topics, all related to either the JeeLabs Energy Monitor, or taking the STM32F103 platform further with Mecrisp Forth. It might not look like much from afar, but...
View ArticleStandalone USB firmware
Announcement: As of today, the JeeLabs weblog is switching into lower gear, as we move towards the Northern hemisphere’s summer recess. Instead of a weekly post plus several articles, there will be...
View ArticleThoughts about app structure
These are some ideas about how to structure the flash and RAM memory for applications built on top of Mecrisp Forth. First off: 64 KB of flash memory turns out to be plenty for very substantial...
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