I'm having a spot of trouble controlling my new STB, a Philips DTR320...

Now the DTR320 isn't "officially" supported by Tivo, but I'm thinking "Hey, it's probably RC5 so it shouldn't be a problem" - indeed, IR code 20053 seems to do the trick.

Well, sort of - nine times out of ten it's fine, but it will occassionally drop the odd digit: ie: key in channel 21 and actually get channel 2, or key in channel 4 and nothing happens.

At first I figured that was just the code speed, so I played around with those - it doesn't matter if a select fast/medium/slow, the effect (and failure rate) remains essentially the same.

The interesting thing with the DTR320 is that the front-panel LED flashes when it receives a command. When you key in a two-digit channel, after a second or so delay while Tivo does its thinking, the LED flashes twice - once for each command. When a digit gets dropped, the LED only flashes once (natch) for a two-digit channel, or not at all for a single-digit channel.

Now the really weird part is this - sometimes you can select a channel (say Channel 4 for the sake of argument). Tivo recognises the keypress and displays the Channel 4 banner. Then you get the BSOD - "Can't display video ect". Then, after an unfeasibly long delay (maybe ten seconds or so), the STB's LED blinks once, and everything springs into life.

It seems that the Tivo itself is either not sending every command (and dropping digits), or massively delaying sending the command(s)

Any ideas? I *really* don't want to revert to my Pace 730!

PS - no leading zeroes (although doesn't make a blind bit of difference), no enter key, front blaster off.

The BSOD will be when you enter a direct channel number on TiVo for a channel TiVo already thinks you are on. So you changed to channel 4 and it failed to change, so you pressed 4 on TiVo's remote again. This is because TiVo assumes you want to switch to channel 4 on its internal tuner.

So try using channel up/down instead of direct entry.

The 20053 codes were not a brilliant capture. Try following some of the advice here: http://www.tivobugs.co.uk/wizard/stb/supported.htm

Thanks for the reply

Your BSOD explanation is very helpful - and thanks for the channel up/down tip. That's one thing that I didn't think of.

My STB sits in its own unglazed cabinet, so it's defininately not getting IR interfence (except when I've got the door open, natch) - I did wonder if the STB's IR receiver was ramping its AGC up too much with it being sat in total darkness, but that doesn't account for the sometimes massive delay between Tivo receiving a channel number and relaying it to the STB.

"The 20053 codes were not a brilliant capture." - Sounds like an industry euphemism for "they're a bit crap". Still, that's useful to know as it's one thing that I don't have direct control over.

I can understand that the whole IR receive/relay approach isn't guaranteed to be 100%, but I'm intrigued by the occassional but significant delay Tivo sometimes has in relaying the commands...

TiVo only normally delays sending out IR codes when it is sensing other IR being transmitted from another device.

Do you have a wireless video sender? These often send out stray IR, as do laptops with IrDA ports, mobile phones with IR switched on etc.

I'm guessing when you've been testing you had the cabinet door open? Do you get channel change problems in real life recording scenarios?

With regards to the codes being crap, it is more that the Philips box uses a toggle bit which TiVo does not support, so can't send this (it always sends this bit in the same position). Most boxes are tolerant of this though to some extent.