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eptheca

TPD + BLM 16x4

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Hi,

I have changed the order of these in the DIN/DOUT chain.

I now have the TPD first then the BLM

I have edited the MBSEQ_HW file, but there is something wrong.

The 4 LED's on the TPD are constantly on, and the BLM acts strange

Could someone please check the attached file, and see if they can see something wrong

Cheers:)

MBSEQ_HW.V4

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i would also like this set up...please let me know if you get this sorted

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At a first glance I don't see a configuration error.

However, I think that this combination can lead to unstable SRIO transfers because of the high number of SRIOs and different chain lengths of the DIN/DOUT SRs. This would also explain, why the BLM acts strange.

A prober solution to overcome this problem is MBHP_LINE_DRIVER: http://www.ucapps.de/mbhp_line_driver.html

I don't know how exactly your hardware looks like, but if the TPD is close to the wilba frontpanel, then it's sufficient to connect the transmitter/receiver between TPD and BLM4x16

Best Regards, Thorsten.

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Thanks for the tip TK.

I don't understand the behavior because I have used it for a while with the TPD connected after the BLM, and it's worked fine.

The only reason I changed it was because I saw that I could get a shorter cable if I connected them in the reverse order.

My hardware looks like thisgallery_7274_109_41507.jpg

On Wilba's frontpanel the DIN/DOUT connectors are on the left side.

On the TPD they are next to each other, but on the BLM the IN is on the left side and the OUT is on the right.

It made sense to me to keep the cable stretches as short as possible, so I tried Core -> Frontpanel ->  TPD -> BLM with the attached config file, but I ran in to the problems mentioned.

I guess I should follow the "If it ain't broke, don't fix it" rule.

I'll just revert back, shut up and make some music   ;)

 

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i have tried this with the Line Driver Transmitter/Receiver...(because i wanted more distance between Sequencer and  BLM/TPD.

But in my case it did not work.....with the linedrivers the buttons/leds were acting strange....

and when i removed the linedrivers and connected it with flatcable...it worked okay....(i know the linedrivers are also okay as ive also used them with the Aout-NG without any problems)

 

 

 

 

 

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No, it won't help.

The problem is, that the TPD has many DOUT shift registers, but only a single DIN shift register (as far as I remember). This results into an unbalanced serial output which leads to trouble when another module with DIN/DOUT registers (such as the BLM16x4) is connected.

So - this kind of module will only work at the end of a serial chain, or with some buffering (and some luck) - it's a complex topic, I can't give you a fool-proven solution without further analysis (and I won't have the time for this anyhow... ;-)

Best Regards, Thorsten.

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The problem is, that the TPD has many DOUT shift registers, but only a single DIN shift register (as far as I remember). This results into an unbalanced serial output which leads to trouble when another module with DIN/DOUT registers (such as the BLM16x4) is connected.

That is right, there are 9 DOUT shift registers but only 1 DIN. It seems best to simply leave the TPD at the end of the chain and ignore the OUT port then.

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OK. I have reverted back, and it works fine like before.

I wanted to add some gate triggers, so I guess I have to add them before the TPD then, or can anyone suggest an easier/better way to add 8 gate triggers?

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As the gate triggers are not arranged in a matrix configuration it should not matter where in the chain they are located. I guess the critical timing issues only arise when matrixing ins/outs. For these (like the BLM), an equal number of DIN and DOUT SRs should precede in the chain to keep the timing undistorted.

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