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Fri, 03 Nov 2006

DECT pcmcia cards
DECT today is seldomly found in the context of PCs. One of the few solutions out there is a Com-On-Air PCMCIA card, originally manufactured by Dosch+Amand, today solely sold by ARC Computer.
They're designed to be used with a Windows software, which then turns the PC to a DECT-VoIP (SIP) gateway.
I got my self one of the Type III and one the Type II PCMCIA cards, but figured out that there's no Windows around here. I hope to get something working on that card under linux, and I can think of more than only a DECT basestation.

As there's no public documentation for the DECT-baseband processor, I probably have to do some (and learn!) reverse-engineering to get linux-support. For now I had a look at the Windows drivers using the HT Editor which seems a brilliant (free) way to reverse-engineer all sorts of Win-SW (and even VxD LE driver binaries) under other OSes.
The CR16 CPU in the baseband processor can be programmed using AS.


- National Semiconductor PCMCIA/PCcard interface PCM16C010 (datasheet, local copy)
- National Semiconductor DECT-baseband processor SC14421CVF, contains a CR16 CPU (no public documentation, share your knowledge!)
- 2kByte microwire EEPROM 93LC86, organized as 1k*16 (datasheet, local copy)
- 512kByte Flash PAI001, only on the Type III card (no datasheet either)
- HCT04 hex inverter
- analog radio Type III card: LMX3161 radio transceiver (datasheet, local copy)
- analog radio Type III card: 2205AF .5W RF power amp
- analog radio Type II card: didn't look at the (availability of datasheets of) devices yet
- only Type III has a LED


If you happen to know anything about
- the DECT baseband chip SC14421CVF or others from the SC144xx family
- the flash PAI001, and why it is only on the Type III card
- the SW architecture/split of the Windows SW that comes with the cards
- any open source driver using the PCM16C010 PCMCIA/PCcard chip (OK, it's documented, but ...)
please contact me and share your knowledge.

com-on-air Type III card HW porn:

top side overall:


PCMCIA controller:


DECT baseband controller:


bottom side overall:


flash and EEPROM:




radio TRX:


radio PA:


com-on-air Type II card HW porn:

top side overall (bottom side has no components):


Type II digital chipset (only differs from Type III in that it has no flash)


radio (all different than on Type III):


Update: the "512kByte Flash PAI001" was identtifies as hex inverter.

4 writebacks


Karsten wrote


I searched for anyone who has thought about get this card work with linux. Did you do any process since your last post?

Rainy greetings
mazzoo wrote

Karsten, some people currently work with the card, and try to get more insight about the workings. However they're not exaclty targetting a linux driver, but probably we can aquire more knowledge on the card.
I had started a linux-driver years ago, but the PCMCIA-descriptors in the card (mem, IO-space) are incorrect, so probably the only path to a linux-driver would involve reverse-engineering the Win-driver.
For a linux driver, today I'd use the new UIO system of the kernel for a simpler to develop userspace driver.

Gtek wrote
Dect sniffer chinese ambassy
That antenna on the chinese ambassy is not an VHF antenna. It's a shortwave log periodic antenna for mainland comms.
harold wrote
Please email me
Hi Mazzoo, love your blog here! I have the type 2 com-on-air card. It works great, and I have no issues as all.. however is the impersonation of a basestation actually supported with the dedected project? I haven't seen anywhere that it can be done.. just people saying it works


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