In Part 1 of this series I have covered the SD card on the Arduino Ethernet shield. In Part 2 I’m hooking up the board to the network and will be able to ping it 🙂
Arduino Ethernet Shield with FRDM-KL25Z
Sometimes it takes a very long time to realize a project. Adding the Arduino Ethernet Shield R3 to one of my Freescale FRDM boards is one of it: it took me a year until I have found a few days to work on using the Ethernet Shield with my FRDM-KL25Z.
FRDM-KL25Z with Ethernet Shield
I have not everything in place yet, so I decided to publish things in parts. So this is about part one: using the Micro SD Card on the Shield.
Character based LCD displays are great: they are inexpensive, and it is rather simple to use them compared to graphical displays. Yes, they only can display text and custom symbols, but this is usually what I need. And pretty much all character displays are using the Hitachi HD44780 protocol, so it is a de-facto industry standard.
HD44780 compatible Dual Line Character Display
These displays have one big disadvantage: they need to be compatible with the original Hitachi interface and protocol. First display were mostly one line only, and had only few characters, typically up to 16. The protocol worked either with one or two lines on the display. Today’s display have usually two lines, with 16 characters. But what if I need more?
4-Line LCD (Source: Daniela Solorzano)
I admit: I have used ARM Cortex cores a lot in the recent months. Yes, I think with the ‘ARM domination of the world’ over time the ARM core will blast away probably all other cores, except for niche players? Still, there are reasons to use non-ARM cores, and even if it is just that I have a board at hand :-).
DEMOQE with MC9S08QE128 and MC13201 Transceiver Card
Tired by the tool chains provided by your silicon vendor? Do you want to use a free and open tool chain? Then you probably followed by “DIY Free Toolchain” series already. In “DIY Free Toolchain for Kinetis: Part 2 – Eclipse IDE” I used the standard GNU Eclipse plugins. As mentioned in above post, there is an even better and more powerful plugin available: the GNU ARM Eclipse plug-ins. There is a dedicated blog site which provides excellent documentation and direct access to new and frequent releases. And these days there is a true a Christmas gift for every Eclipse lover: the version 1.1.7 with the addition of J-Link debugger plugin :-).
GNU ARM Eclipse
Time to write an update about the RNet Wireless Stack. The stack has been successfully used for the Sumo Robots as wireless controller. In the last week, there has been a lot smaller and larger extensions for it. And because the nRF24L01+ modules are so inexpensive, I bunkered more than 50, with 20 still left to be deployed:
nRF24L01+ Transceiver Modules
The good thing with the internet is: it allows engineers to collaborate. And here is an example: Marc is a reader of this blog had a problem with the I2C hardware of a Freescale Kinetis ARM microcontroller. In his case, the I2C bus could be stuck, and there seems no way to reset it with the I2C hardware on the microcontroller. So a solution would be to reset it with software instead.
Bit Banging Software I2C Driver
I was searching the internet for an open source network stack for my nRF24L01+ transceivers. But these stacks were either too heavy or had a restrictive or not really non-open source license behind it. I was very reluctant to start with something I think already should exist. Two weeks ago I decided that I just do it from scratch, and here I am: I have the basics working 🙂
Two FRDM-KL25Z with nRF24L01+ Transceivers
So this tutorial is about using a terminal connection between my board and my host (e.g. a notebook) to read and write text:
Color Text in PuTTY
In my earlier post “S-Record Generation with gcc for ARM/Kinetis” I documented how to have the ARM GNU gcc toolchain to produce a S19 (Motorola (or now Freescale) S-Record) file. Here are a few more tips on that subject:
MCU on Eclipse 