Linux Drivers

November 2013

Linux benchmark on Xilinx Spartan-6 LX45 (SP605 evk)

I was asked to give at least a generic insight of “how fast” would Linux run in a Microblaze soft-CPU running on a Spartan-6 LX45 processor (specifically on the SP605 evaluation kit). Of course it has to be clear that the usage of such a processor/environment cannot focus on pure performance reasons, as you usually choose a FPGA for other reasons. For pure performance there are much better solutions (hardware based CPUs indeed) or if you need also the FPGA advantages processors with both a FPGA part and a hardware CPU, such as the Zynq family processors for example.

Linux Linux Drivers Linux Embedded Microblaze Nbench Petalinux Sp605 Spartan-6 Xilinx

2 minutes

February 2013

Linux iMX23 audio loop (or using the iMX23 as an amplifier)

As usual when working with embedded systems every component saved seems like gold to the HW guys (no matter how much software hassles or future limitations this may cause!) and in this context lately I’ve been working on the idea to use the Freescale iMX23 processor, that was anyway present in the project for other needs, as an audio amplifier to pilot a small speaker with no special volume requirements. Basically the output of a GSM module (audio out) was connected to the MIC input of the iMX23 and then the output to the speaker, just with little strictly needed passive electronics in between. As by the datasheet the processor should be able to pull out till 1.9W at 4Ω and there were some interesting registers to play with, even if not documented so very clearly nor seemed to be used anyhow in the audio driver provided. The software base used was the LTIB based BSP provided by Freescale, including their kernel patches for a 2.6.31 kernel.

Audio BM_AUDIOOUT_TEST_ADCTODAC_LOOP Drivers Embedded Freescale Imx23 Linux Linux Drivers Linux Embedded Loopback Teaching Material

4 minutes

January 2013

How to cross-compile under Linux

Recently I’ve been asked by a few people how to crosscompile programs/packages under Linux. This happened especially after the article on customizing the DGN2200v3 (you can find here) but also for work reasons. In this article I’ll try to give some insights on this operation that is often feared, but is generally not a very hard task (yes I said generally: try for example crosscompiling something like the openjdk and you’ll understand what I mean!). This article will try to be generic but with some more examples on the DGN2200v3 crosscompilation and some ARM references. Get and install the right tools The first thing to do if of course to install on the system you are working (which is called host system) the tools that run on the host and will permit you to compile something for the target system you want to compile the programs for. This set of programming tools is usually refeered as a toolchain and contains various things: usually one or a few compilers, one or a few linkers, an assembler, various header files, little or a lot of libraries and other simillar tools. If you are lucky you may get also a debugger packed. All this tools of course are compiled to run on your host machine but produce binaries that run on the target. Depending on how the toolchain was created you may also find supplied with it some set of tools that are ready to be run on the target to help your crosscompilation adventure. This operation may be very easy if you somehow received the crosscompiler package ready (as for example the DGN2200v3 you just download it from the Netgear site or you collegue may have passed it to you) as you just have to unpack it somewhere and then refeer to it.

Arm Compile Cross Crosscompile Dgn2200v3 Embedded Linux Linux Desktop Linux Drivers Linux Embedded Mips

11 minutes

December 2011

ftdispi, a library for interfacing SPI devices with FTDI based USB to JTAG dongles

ftdispi is a small library that can be used to interface SPI devices to FTDI based USB to JTAG interfaces. It is based on libus-1.0. It was tested with the Xverve Signalyzer (USB VID 0x0403, PID 0xbca0). Have a look at the included example testftdispi.c for usage instructions.

Drivers FTDI JTAG Linux Linux Drivers SPI USB

1 minute

December 2009

Hardware JPEG2000 on Linux

Eurotech CTR1474 Linux driver. This is a powerful PC/104 board for DVR applications. It features an JPEG2000 codec and TWA2835 video processor.

Driver DVR Eurotech Linux Linux Drivers Pc104

1 minute

December 2006

Serocco PEB/PEF 20532 Linux 2.6.12 driver

Serocco driver. Linux 2.6.12 device driver for the chip “Serocco PEB/PEF 20532”

Driver Linux Linux Drivers Serial

1 minute