Composite video from FPGA
Last week’s setup was just for warm-up – I wanted to understand the signal generation before bringing it over to an FPGA. Here is the same signal, generated by the same µC, but passing its data through...
View ArticleTying into SDRAM
Synchronous Dynamic RAM is perhaps the most common form of random access memory - it’s large (MBs, vs SRAM’s KBs), it’s fast (supporting 100 MHz and higher), and it’s low cost due to the widespread use...
View ArticleSo many memories
An EP4CE6 FPGA has 30 KB of built-in “Block RAM” memory. Fast, but limited in size. With SDRAM, you can have megabytes more, but it’s not quite as fast and harder to interface to, due to the periodic...
View ArticleA fast µC to FPGA bus
For reasons which will become clear later, I’d like to exchange data quickly between an STM32 µC and an FPGA. SPI is a serial bus, which can be pushed to several dozen Mbit/sec - but what if we want...
View ArticleBlu-Ray safety copies
Having been bitten by data loss occasionally during the past decades (several of them dumb “operator error”, I must admit), I’ve adjusted my backup strategy a few times. Since I live in an “all-Mac”...
View ArticleGetting started with STM32
ARM Cortex microcontrollers are incredibly powerful 32-bit computers - many not larger than the size of a fingernail, and able to sleep with just a few µA of current draw. There’s a whole bunch of...
View ArticleInteractive development
Most readers will be familiar with this view: Now that you’ve seen how to build software and run it on the Blue Pill in the traditional way, I am going to switch gears radically: Stop staring at that...
View ArticleThe upcoming JeeNode Zero
Lately, I’ve been keeping busy with a brand new board. It’s called the JeeNode Zero: Shown here is the “rev3” prototype, and it’s starting to shape up nicely. Sooo… without further ado, let me tell you...
View ArticleLet's have some fun with a JNZ
Since the JeeNode Zero adopts a new µC architecture, a new layout, a new runtime library, a new programming language, and new drivers, there’s a lot of work ahead to describe all the parts and how to...
View ArticleVarious shades of Forth
This week’s episode will cover a variety of aspects related to Mecrisp Forth: Using Linux i.s.o. a SerPlus - Wed Forth over USB on STM32F103 - Thu Performance and I/O toggling - Fri As always, these...
View ArticleThe upcoming JNZ rev4
Now that the JeeNode Zero rev3 has been out for a few weeks, I’ve made a few more changes before it goes into production: I’m calling it “rev4” for now, but expect it to be virtually identical for the...
View ArticleVarious JNZ developments
While waiting for the next JeeNode Zero revision, I’ve started on some examples and documentation for this new fun ecosystem. So there’s a bit of everything this week: Analog over wireless - Wed...
View ArticleThe JeeNode Zero rev4
It’s official: the first batch of JeeNode Zero rev4’s has been assembled, pre-loaded with software, and tested. Currently in transit from NL to the UK shop. It’s real now: There are a number of...
View ArticleA wireless rotary encoder
This week, I’ll be playing around a bit with a rotary encoder, wireless, and an OLED: But first, a brief tale of a belated little bug which caused a few surprises… Post-mortem of a bug - Wed Connecting...
View ArticleBring in the Pies!
For production, fast re-flashing and testing of each JeeNode Zero is going to be a must. This week’s episode will be about speeding up the uploads, but also several ways to debug and test any STM32...
View ArticleNo milk today...
Yikes. I’ve been felled by some bad stomach cramps and fever these past couple of days. Hence no articles this week - my apologies! The blog will resume next week, stay tuned.
View ArticleKeeping busy (in Forth)
Serial ports, radio packets, I2C devices… it adds up when you’re trying to keep many activities going at once. Luckily, there are some nice packages for Mecrisp Forth to help with this… This week, I’m...
View ArticleSD cards, interrupts, and DMA
This week is another potpourri of code for the STM32F103, the purpose of which will become clear next week… suspense! SD cards and µSD cards have a ridiculous amount of storage in a very small package....
View ArticleEZ-Retro is a Z80 running CP/M
And now something completely different! I’ve always been fascinated by those 8-bit computers that started it all. As a teenager, I spent many hours reading about them, but never could afford a Z80...
View ArticleEZ-Retro Z80 - part 2
Getting CP/M working on this two-chips-plus-a-blue-pill setup took more time than I thought, especially on the software side. This week, I’ll turn Forth into a peek-and-poke monitor for the eZ80,...
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