Recently I’ve trying to use Freescale’s C90TFS Flash Driver for erasing and programming on-chip flash on their Kinetis MKL25Z128 Cortex M0+ processor. This is the same processor as used on the Freescale Freedom board. At the time of writing, the…
New Project Posted – RF Signal Generator
There’s a new project posted on the main website – a simple RF signal generator that (mostly) covers the range 640 MHz to 5.8 GHz. The project can be considered as being in two halves. First is the RF half.…
Freescale Kinetis USB Bootloader
I’ve been doing some work with a Kinetis MKL25Z128 Cortex-M0+ processor. I love what you get for the very small amount of money this thing costs. It even contains a 16 bit A/D converter, which is very rare at this…
FreeNAS Weekly Status Email
Older versions of FreeNAS would email periodic status reports, however the newer 9.x versions no longer do this. FreeNAS now only sends emails when something strange or bad happens. It makes sense – lots of “everything’s fine” emails tends to…
Building a Do It Yourself NAS
Introduction NAS (Network Attached Storage) devices, also known as a home server, are pretty common these days. They’re great for having a central point to store files; as a media server for holding photos and home movies; as a place…
STM32F2xx / STM32F4xx DMA Maximum Transactions
It’s funny how a topic as apparently mundane as the DMA controllers on the STM32F2xx and STM32F4xx processors can be such a can of worms. I’ve already provided 2 postings on the subject, here and here, and now we have…
STM32F2xx / STM32F4xx SDIO Interface Part 2
Here’s the link to Part 1. A very significant limitation with the STM32F4xx family (STM32F405 / 407 / 415 / 417) is that fully a third of its internal RAM is inaccessible to the DMA controller. Of the 192 kB…
STM32F2xx DMA Controllers Part 2
The discussion around the STM32F2xx and STM32F4xx DMA controllers is becoming a bit too large for a single posting, so here we are with Part 2! Clearing a DMA Interrupt In theory this is very simple – in practice not…
Class 10 SD Card – Or Not?
Recently I purchased a Class 10 SD Card from a major retailer. I was very excited – now I have a fast card for testing. Here’s my new baby: Note the 10 in the part-circle indicating the speed. For those…
STM32F2xx SDIO SD Card Interface
The STM32F2xx has a great SD Card interface. It’s a true 4-bit parallel interface, and in general it works pretty well. I have come across a few, fairly minor but still significant, considerations when using the interface that I thought…