Author Archives: Nils

Coron Wah-Pedal W-220

Technical review of the Coron Wah Pedal W-220 Continue reading

Posted in effects, guitar | 1 Comment

LPC Microcontroller flash checksum utility

Wrote an utility to fix something annoying in my micro-controller work-flow. If you’re coding for the LPC17xx micro-controllers under Linux using OpenOCD and the GNU tool-chain you’re likely familiar with the following message during flashing: Warn : Verification will fail … Continue reading

Posted in Uncategorized | 1 Comment

SWP Tracer/Sniffer

It’s possible to modify the SWP Transceiver front-end circuit presented earlier to a full functional SWP Tracer/Sniffer. This is almost the same circuit as the SWP transceiver but I moved some parts around to make the signal flow a bit … Continue reading

Posted in Uncategorized | 2 Comments

SWP Reader – The Analog Part

SWP Reader Analog Front-End Continue reading

Posted in Uncategorized | 12 Comments

SWP Reader Evolution

I’ve been working on my SWP reader for about a year now, so I think it’s a good time to dump some photos and show how the project evolved: The first “proof of concept” prototype: For this prototype I decided … Continue reading

Posted in Uncategorized | 5 Comments

Ultra simple ISO-7816 Interface

While laying out a PCB for my SWP reader project I realized that I haven’t ever tested the ISO-7816 (aka contact) interface yet. I probably forgot that because it’s not all that difficult and not that interesting, but I’d rather … Continue reading

Posted in Uncategorized | 4 Comments

NFC SWP Physical Layer – How it works

As I’m currently building an NFC-SWP reader device I have to tackle quite some challenges simply because there there is no single chip solution out there that you can simply connect to USB and a SIM card. Most NFC Controllers … Continue reading

Posted in Uncategorized | 3 Comments

About a failed Circuit Idea

I had a circuit idea in mind that I’ve never been able to try out. I’m working on a SWP reader device right now (that’s a device that should directly talk to NFC enabled SIM cards). So recently while browsing … Continue reading

Posted in Uncategorized | 18 Comments

DSP default cache-sizes not optimal?

While debugging some DSP code yesterday I came a cross a performance oddity. Adding more code lowered the performance of an unrelated function. By itself this is not *that* odd. It happens if the size of your code is larger … Continue reading

Posted in Beagleboard, DSP, OMAP3530 | 8 Comments

Faster Cortex-A8 16-bit Multiplies

I did a small and fun assembler SIMD optimization job the last week. The target architecture was ARMv6, but since the code will run on the iPhone I tried to keep the code fast on the Cortex-A8 as well. When … Continue reading

Posted in Beagleboard, OMAP3530 | 6 Comments