Re: infra-red keyboard / mouse protocols

Has anyone got any information about this?

> > I'm guessing there is no standard, but since such keyboards exist has

anyone

reverse-engineered them to find their protocols. > > In particular, for the NTL internet TV keyboard. > Sending emails via the handset is a PITA, > and NTL charge a lot for their keyboard. > > Surely it should be simple for a cheap micro to talk to a normal 5 quid > keyboard and emit the required signals.

I have an NTL keyboard and sending emails with this is still a PITA. It's not the keyboard/handset that is the problem, it is the appalling software in the STB and the back end servers.

The "truth" about the IR standard used by NTL STBs is hotly disputed. Some say it is IrDA. My STB is for an original NTL franchise area (not ex-CWC) and would appear to use common RC5 encoding.

The NTL keyboard is based on the Chicony KB9820 and this keyboard is available overseas (Eastern Europe, USA) for PC use with standard keycaps and an IR module that plugs into the PCs keyboard and mouse ports.

It's one of the things on my "To Do" list to wire up an IR transmitter/receiver pair to an AVR uController so that I can use my otherwise unused NTL keyboard with a PC.

Reply to
Juan Lauda
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My NTL STB is made by Pace.

I agree the software is appalling.

The user interface is so badly designed that it can't show the full channel or programme names, it crashes so badly it needs to be unplugged, and when it powers up it blatantly lies that NTL are upgrading the service. They spent loads of time and effort advertising the interactive button, which usually crashes the box. I don't know how they have the nerve to present it as a finished consumer product.

I scoped the handset signals, they look like RC5. I doubt they would go to the effort of writing an IrDA stack.

How did you find this out? Can you use it in place of the NTL/Pace keyboard?

The Linux InfraRed Remote Control website

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is interesting.

K.

Reply to
kryten_droid

Mine too, DI-4100 or something... AFAIK, they are all made by Pace, even the CWC ones.

That's what I thought. Over on the home-cinema newsgroups they swear blind that it's some kind of IrDA and that's why the IR blasters on most VCRs don't work with the NTL STBs. I told them that my Panny VCR is happy to control my STB if I tell the VCR that my NTL STB is really a Philips Canal+ box. I said that Philips invented RC5 and therefore it's probably not IrDA, especially as none of the IrDA sniffers that I have used recognise the NTL keyboard. No one believed me...

keycaps

I saw some pictures of IR keyboards for sale on a US web site. Apart from the colours and keycap legends, the keyboards looked almost exactly like the NTL one. "KB9820" is stamped/moulded on the back of my NTL keyboard so I Googled. The rest, as they say, is history...

No idea. There's some kind of mask ROM/controller inside the NTL keyboard. You would think/expect that all the KB9820 models sent the same RC5 codes and that the STBs decode them directly and the PC keyboard thingy converts them to scan codes and stuffs them down the PS/2 port. The NTL keyboard transmits when you press a key and again when you release the key, so this fits in with the way scancodes work on a PC. I don't know if N-key rollover will work though...

I'll take a look...

Reply to
Juan Lauda

Aha, then

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indicates those are definitely RC5! # model: DI4001N # supported devices: DI4001N (NTL UK Digital Cable box)

Doesn't cover the keyboard codes though.

From the file, I can't spot the system codes easily. I need to look at the C code.

I'd guess the NTL keyboard combines the KB9820 and the IR widget.

AFAIK, RC5 does not include keyboard codes (it would need too many) so it may use a different protocol for them.

Agreed.

That's useful information.

K.

Reply to
kryten_droid

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is RC5 based.
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is Ruwido rMAP as I recall, only the one I remember was blue and was a different design (maybe that was the one that used the NEC protocol). The Telewest box uses Two-way TV protocol which _is_ based on IrDA. The Pace boxes use a custom IC from Two-way TV that decodes the Two-way TV packets into something that's suitable for attaching to a UART. No stack writing involved.

Makes no odds, they're all easily scoped and replicated, IrDA or not, as has already been pointed out.

Reply to
auser

Do bear in mind that the NTL keyboard is made by Chicony, not Ruwido.

Reply to
Juan Lauda

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