Problem with Kramer VS808XL Switcher

pdanford

Has anybody out there successfully controlled a Kramer VS808XL a/v switcher?

I can't seem to get this guy to work. I can send single commands with success, but when I try to send multiple commands, say in a single button event, the switcher responds intermittently - like only doing 2 of the 3 switches. My first though was timing, ie- switcher not able to process fast enough to multiple strings at once like other switchers I've seen, but my usual workaround - using WAITs between strings, or TIMELINES or DELAY, hasn't worked. No matter how I time it, or even if I put seperate strings with CR, it still only responds intermittently. I checked the wiring, all ok. Talked to Kramer, which wasn't that helpful since they are based in Israel and there seems to be no technical staff familiar with the RS232 in the US.

Any info is appriciated.

pd

Chip Moody

I worked with one of these just recently. On the advice from a Kramer tech rep, I spaced commands out by 3 tenths of a second - no problems...

- Chip

Darkside

Kramer V Kramer

I never like getting on a manufacturers case too much, but sadly here goes.

We have found the Kramer serial control hardware/protocol is at best, flakey. There are success stories around I'm sure, but I suggest they are in the minority!

Tech support is as good as you suggest.

We have seen many of these units (and indeed others such as matrices) behave EXACTLY as you describe. They appear to become less stable when serially daisy chained - assuming you can work the manual out to get THAT to work!

I ended up slowing the rate-between-strings right down to 'wait 8' and issuing a safety (duplicate) string. I truckload of traffic sadly, but more than halved the error rate in the end. The modules serial output section handles this internally. There have been odd reports of the output not being correct, but the code allows a re-press of the button which inevitably sorts it out..

I started to suspect the unit may go off to la la land waiting for sync on an input before it can sit down and process the next string from the buffer. I never confirmed that.. (This came up in a system with 8 floor boxes and obviously not all 8 sources always present). This sort of behavior actually occurs on some projectors - which is where the thought came from

IMHO, these guys make widgets and gadgets like DA's reasonably well, not systems products. Pick a matrix like an 8x8 RGBHV. Fancy having to issue 8 strings to patch input 1 to outputs 1-8...enough said.

bano

pdanford wrote:

Has anybody out there successfully controlled a Kramer VS808XL a/v switcher?

I can't seem to get this guy to work. I can send single commands with success, but when I try to send multiple commands, say in a single button event, the switcher responds intermittently - like only doing 2 of the 3 switches. My first though was timing, ie- switcher not able to process fast enough to multiple strings at once like other switchers I've seen, but my usual workaround - using WAITs between strings, or TIMELINES or DELAY, hasn't worked. No matter how I time it, or even if I put seperate strings with CR, it still only responds intermittently. I checked the wiring, all ok. Talked to Kramer, which wasn't that helpful since they are based in Israel and there seems to be no technical staff familiar with the RS232 in the US.

Any info is appriciated.

pd

I had the same problem so I wrote a queue, modified from a code block I found written by amx for another piece of gear.

NMarkRoberts

A coupla things...

(1) Kramer makes a LOT of different stuff and I guess they have a lot of different engineers who perhaps vary in ability.

My experience with Kramer hardware, protocols and support has been uniformly excellent. I even count the very prompt replacement of a faulty unit as "excellent" in its own way.

It does help living <5km from the national distributor ;^)

(2) Given that a large proportion of what we all do is queueing multiple commands to send to serial-controlled devices with ACK/NAK responses, surely everyone has a command-queuing include that they use for all such modules? You only have to write it once...

pdanford

Thanks for all the replies everyone!! Nice queueing mod bano! After trying various things I was able to get about a 95% success rate using the CHARD command, and WAITS between individual actions in the same button event. ie-

ONLINE:
{
SEND_COMMAND KramerSwitcher,"'CHARD-400'"
}

then in the button event:

WAIT 0 SEND_STRING KramerSwitcher,"'ACTION 1'"
WAIT 1 SEND_STRING KramerSwitcher,"'ACTION 2'"
WAIT 2 SEND_STRING KramerSwitcher,"'ACTION 3'"

and so on. I was still able to trip it up if I switched really fast, but 19 out of 20 times it worked. So it works, but I'll stick to Extron switchers in the future...

Thanks all.

DHawthorne

Though stacking WAITs like that will work in many places, like Mark says, you ought to consider writing yourself a simple queuing routine for multiple commands. Store your commands in a buffer, and fire them off one at a time. As stated, you only have to write it once, then adapt it to every project. The code I am using is essentially the same I have been using since Axcent3 days.

It may not matter in this particular application, but if you have a queue you can pause it, clear it, interrupt it; firing out a bunch of WAITs is pretty final unless you name them - they are going out no matter what. And naming them all independently and keeping track of all the names so they can be canceled is kludgey beyond anything you want to get involved in .