Meridian Unplugged - Powered by MrTechGuy.co.uk Forums Discussion Off Topic OT: Panja -vs- Crestron

First, this Boston stuff is interesting. I actually used to live in New Hampshire (Merrimack, then Amherst), but moved away at the end of 1993. I spent 10 years bummin' around the Boston area. Kathi (then my girlfriend, now my wife) couldn't stand the snow, black flies, mosquetoes, etc, and made it pretty clear that if we didn't move, she would. Since Kathi was pretty important to me, I viewed that as an important safety tip on how to keep Kathi hangin' out with me!

Anyway, back to the subject of this thread:


I totally disagree with this! First, yes, some devices don't work well (such as a cable box), but that's why you use a video sync sensor. That works perfectly on a box that draws minimal power when on vs. off. I have a LOT of gear, and I have yet to not be able to sense power.

Second, even when I do have discrete power controls, I still do power sensing? Why?

• Many devices (Meridian 861, most Sony TVs, my Yamaha receiver, etc) doesn't accept commands for a brief period of time after powerup. Thus, if I know that the unit was off, I know that I need to wait a bit before sending further commands. Sure, I can always wait (in case it was off), but I prefer my system to be as fast as possible. By sensing power, I can optimize how quickly things happen.
• Some devices may behave slightly differently on power up. For example, depending on configuration, the Sony G90 may go into a "warm-up" mode (all white screen). If I know that I just powered on the projector, I can query to see if we're in warm-up mode and cancel it (depending on how the system was powered up).
• You say things get "broken if the user uses the original remote or uses front panel controls". And that's exactly WHY you'd do power sense! No matter what the user does (front panel, original remote - which we don't have out anyway, those are all put away - no need to use them with the Panja automation system), with power sense, we can make sure that the system is in a reasonable state.
• By doing power sense, I can be optimal in my use of RS-232 commands and I/R blasts. For example, why send an ON command when I don't need it, and why wait 2 seconds in case the device wasn't on? Instead, if I know the TV is on, for example, I can just send the command I need. When I want to turn my gear off, why send 10 commands out when one or two would suffice?

Sure, I have discrete power commands for my Sony TVs, and for my Sony G90, and for a bunch of other gear. Sometimes I even use them (although it generally doesn't matter). But, in all cases, I still have found useful purposes for power sense - stuff that I absolutely needed power sense in order to do.

As far as I'm concerned, discrete commands (at least for power) are critical if you have a "dumb" remote (i.e. a Pronto, for example, that has no state). But if you have an intelligent, computer controlled system, discrete on/off is a big yawner.

Other discrete commands (i.e. discrete video commands) might be nice for the Sony TVs, but it generally takes, at most, 2 or 3 I/R blasts to get those to operate in a discrete fashion, so that hasn't been all that important. And, other than the Sony TVs (which can trivially be worked around), everything else I have already has discrete I/R for everything I need.

Just my opinion, anyway, based on a fairly well-tuned home automation program.

[This message has been edited by Jeff Coffler (edited 05-08-2001).]

my apologies, geoff! my guess is that people confuse it 'cuz of "greynolds" - at quick glance it's pretty easy to read "greg" out of the "grey". not an excuse, just an observation. sorry!

sab

>I totally disagree with this! First, yes,
>some devices don't work well (such as a
>cable box), but that's why you use a video
>sync sensor. That works perfectly on a box
>that draws minimal power when on vs. off.

This will work fine on a cable box with a video output, but the cable boxes used by our cable company only have an RF output. In my case, the box I'm using has a switched power outlet, which is what I use for power sensing.

>I have a LOT of gear, and I have yet to not
>be able to sense power.

My opinion is to follow the KISS principle with these things. Why sense power when you don't need to? Your point about some devices not accepting additional commands for some amount of time while powering up is certainly a good reason to consider using power sense and there are others. But in many cases, using a power sensor instead of discrete power commands only makes the system more complex, expensive, and prone to failure (as you've introduced yet another device that could break). My opinion is to use discrete commands whenever possible. If you have a good reason to use a sensor in addition to or instead of, go for it.

>You say things get "broken if the user uses
>the original remote or uses front panel
>controls". And that's exactly WHY you'd do
>power sense!

But this only solves the problem for power. Discrete commands also solve this problem for power. For other things, such as selecting a specific video input, discrete commands are incredibly useful.

>No matter what the user does (front panel,
>original remote - which we don't have out
>anyway, those are all put away - no need to
>use them with the Panja automation system),
>with power sense, we can make sure that the
>system is in a reasonable state.

There's no need for the original remotes in a Crestron system either, but I thought the example might help make my point a bit more clear. Discrete commands make sure the system is in a reasonable state too, with far less cost than purchasing a sensor.

>As far as I'm concerned, discrete commands
>(at least for power) are critical if you
>have a "dumb" remote (i.e. a Pronto, for
>example, that has no state). But if you
>have an intelligent, computer controlled
>system, discrete on/off is a big yawner.

I guess we'll have to agree to disagree on this. I certainly accept that some of your points are valid, but if one wants to keep the system relatively simple (and at a reasonable cost), discrete power codes definitely have their place. Even if using power sense for the other benefits, why not send the discrete power commands if available anyway?

>Other discrete commands (i.e. discrete
>video commands) might be nice for the Sony
>TVs, but it generally takes, at most, 2 or
>3 I/R blasts to get those to operate in a
>discrete fashion, so that hasn't been all
>that important. And, other than the Sony
>TVs (which can trivially be worked around),
>everything else I have already has discrete
>I/R for everything I need.

I thought you wanted your system to work as fast as possible. Isn't 1 discrete command always going to be faster than 2-3 work around commands? What about a device that simply has next/previous video commands and no way to get to a known state (such as many TV's, especially older models)? The obvious answer to this is that these devices often don't have discrete commands anyway . But I hope you can see my point here.

Geoff

[This message has been edited by greynolds (edited 05-12-2001).]

Hi Geoff,

I can see your point that discrete commands (especially for non-power uses) are nice, sure. 2-3 I/R commands are clearly longer than 1 I/R command.

On my Sony TV's (which only have a "next" video input button), I find that doing a 2<Enter><Video> will absolutely discretely get me to Video One, regardless of prior state. Now, if it's very convienent to collect I/R to do discrete operations (i.e. if it was already in my .IRL file for the device, or very very easy to get in there), I'd certainly use it. But if it's short and easy to work around it, I generally do that. That way it works on any system anywhere, and it's easier to share my source code without saying "Oh, wait, you need these special I/R codes as well, or the code won't work".

In the case of power, I guess I just never ever do uncontrolled I/R of power signals, even with discrete power.


It doesn't "cost" me anymore to power sense than not. NetLinx I/R cards come, built in, with contact sense ports since it's so common to sense power on I/R devices. So the hardware is "there"; it's only a question of if I choose to use it or not.

So, since I like to avoid needless I/R, I already do things like:

if (!VCR_PCS) PULSE[VCR,PWR_ON]
(or something like that).

Now, in this case, PWR_ON could be a toggle power, or it could be a discrete power. In either case, I don't really care. Because regardless, the system will work identically, and the VCR will turn on IF needed (otherwise nothing will happen).

You ask "Why sense power if you don't need to?" Well, in response, I guess I've never had a situation where I didn't need to. It's so easy to test power, I invariably test, even if just to reduce the I/R output and get the device up/running as quickly as possible.

-- Jeff

quote:
--------------------------------------------------------------------------------
It doesn't "cost" me anymore to power sense than not. NetLinx I/R cards come, built in, with contact sense ports since it's so common to sense power on I/R devices. So the hardware is "there"; it's only a question of if I choose to use it or not.
--------------------------------------------------------------------------------

Am I correct in assuming that you still have to purchase the sensors that hook up to the contact sense ports?

Most of the Crestron systems (everything beyond the base ST-CP control processor) come with contact sense ports, but not tied to the IR ports. Personally I prefer this approach, as you simply purchase what you need beyond what the system comes with from the factory. If you need to sense current for every device, you simply make sure you have enough analog or digital inputs as appropriate.

Am I correct in assuming that you could use the sense ports on your Netlinx cards for whatever you want, or are they pretty much tied to the specific IR port?

In any event, it's clear that we take slightly different approaches to programming our systems. Personally, I think that's a good thing as it allows each person to be creative in how they do things and there's no one right way to do everything. It seems like we're both happy with our systems, which is the bottom line in the end.

Geoff

With NetLinx, it is assumed that I/R devices will need to be power controlled, so NetLinx I/R cards come with contact inputs as well. You can tie the two directly together, if needed. But you need not do this, and the contact inputs could be used for other things as well.

Sometimes it makes perfect sense to tie the two together. For example, when I had a standalone TiVo that controlled a DSS receiver, I had to make certain the DSS receiver was on at all times. So I tied the DSS I/R port to a contact port, instructed NetLinx that I wanted the device to be on all the time, and NetLinx took care of the rest, even after power failures or other problems.

Another case where I do this: An old receiver that my wife uses has the annoying issue that it defaults to "On" after a power glitch. So that's tied to the I/R port, and if it comes on unexpectedly, the system will automatically turn the device off. This is without "programming" (just one line, at boot time, to instruct the system of what I want).

In any case, an I/R card comes with 4 I/R ports and 4 contact ports. The contacts could be used for anything. Or you could get a separate contact card (10 inputs) if you need more.

-- Jeff

I already had gathered that. What I was asking was what do you have to purchase to connect between the device and the contact input? Essentially, I'm wondering if Panja may have some sensors that could be used with a Crestron system. Crestron's approach to current sensing is actually slightly different. If you want video synch sensing, you purchase their ST-VS box, which has 4 video sensors that interface directly to the rest of your system without a need for contact inputs (each video synch sensor include a passthrough jack). Similar for current sensing, but they have boxes with 1 or 2 sensors. They also have analog and digital ports (aka contact sensors), but don't sell power sensors (current, video, TV probe) that will work with them. I've been using SmartLinc probes (from Smarthome.com) for now.

Geoff

[This message has been edited by greynolds (edited 05-15-2001).]

Hmm, why not just use the products they have that don't require interface cards (like the ST-VS box)?


Got it. Couple of choices:

• If the device has a switched output, then (of course) just plug a wall wart into the switched outlet, take that to a contact port.
• If the device draws considerable power (a receiver, or a TV), use a PCS or PCS2. These will sense power draw and provide contact sense if the device is off/standby/on.
• If the device draws a small amount of power, use a VSS-2. These have two pass thru composite inputs (but I generally don't bother to pass thru, since I use S-Video) and provide contact sense if the device is off/on.

PC/PC2/VSS2 should all be able to be found on their WWW site. Let me know if this answers your questions.

Mostly due to cost. I only needed a couple of video sensors and a couple of current sensors (for switched outlets on my cable box and receiver). The Crestron ST-VS costs around $600 and gives 4 video sensors. By purchasing a ST-IO (my control processors is currently the ST-CP, so I had to buy something extra), I have more flexibility (and fewer boxes) when combined with the various types of sensors available from Smartlinc. The one problem with the Smartlinc sensors is that they tend to be a bit sluggish, so I may purchase a ST-VS at some point.


After I posted my previous message, I went to Panja's site and found these. They are pretty much equivalent to what Crestron offers, but require a contact sensor port instead of a "network" (Cresnet or Panja network) connection. So in the end, I think either the Smartlinc sensors or the solution from Crestron are the best solutions for me. For you, the best solution would be either the Smartlinc sensors or the solution from Panja. Based on what I've seen, mixing and matching between Crestron and Panja is not the optimal solution.

Geoff