tashikoma

SEQ V4 STM32F4 +BLM Hardware questions

11 posts in this topic

Hi everybody,
After have build SEQ v4 with STM32F1 with options (ethernet / 4x IIC midi / AOUT/ BLM port) no wilba CS/ homemade frontpanel (lots of DIN DOUT) some years ago... (and working very well)

I'm building a new SEQ V4 with STM32F4 and Wilba CS/schaeffer frontpanel with:
Line Driver transmetter
2x MIDI IO
IIC Midi
ethernet card from the fist seq
BLM port

a separate rack with Line Driver receiver ,AOUT and DOUTx4 for gates/triggers

Questions:
I don't find informations for the BLM port with STM32F4!
someone say on a forum that the second MIDI IO will be for this purpose:
what is the best way to have BLM port with STM32F4? how to wire?

Is MIDI IO with STM32F4 provide 3V or 5V midi ? (does the MIDI IO stuffed with 220 ohms or 47 ohms resistors R3 R5 R8 R10?)

Is the config of LineDriver is Plug n' Play? you could use the seq without Line Driver receiver or have to plug parallel port permanently?

Thanks

 

Edited by tashikoma

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hi there

 

the BLM is connected to the din/dout chain..(its J2 on the wilba CS pcb)...but you must change the HW file on your SD-card to get it working...link to hw file can be found at the bottom of the page here: http://www.midibox.org/dokuwiki/doku.php?id=tpd_pcb

 

i always stuff the midi IO with 220 ohm...works fine for me.

if you build the linedriver...it works plug n play and the seq works fine without line driver receiver...but i notice some difference in dsplay brightness...if it is connected

 

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Thanks electrodancer

i was thinking external BLM 16x16 needs midi in and out port to work not the din/dout chain.
i need to exactly define my setup before start drilling the midi rear panel!

let's go for 220 ohm!

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See the hookups for SeqV4 users on the Line Driver page, this is the suggested usage if you use a Line Driver module with Seq V4. Line driver. Also you get a BLM port on the Quad IIc module, available at Smash TV, this hooks directly to the core connector J4A

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I think there is a little confusion here,  tashikoma and electrodancer are talking about different BLM's. I guess electrodancer is taking about the 16x4 BLM which uses the din/dout chain where as tashikoma is talking about the 16x16+X BLM which connects via MIDI. 

 

Im also going to be building one of the 16x16+X from the recent group buy to connect to a STM32F4 core. At this stage I haven't found any specific documentation on how the BLM port should be connected but in my case I'm guessing it will chain off the end of the MIDI I/O board & appeare as MIDI I/O port 3.

 

My configuration is:

SMT32F4 core

1 X MIDI I/O board

1 X IIC MIDI board

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Thanks to all.

Yes Rowan we talking about different BLM and i don't find spécific documentation about the BLM port(16x16 external) and coreSTM32F4... all the doc are for previous core.

slo the connector of BLM port on quad IIC midi module don't match with J4A!( the IIC bus for IIC midi) but seems to be at the place of the second MIDI IO board.(at J2 not pin matching)

I think the BLM port will be on dual reserved midi IN/OUT , BLM schematic: Mi1 MO1 MI2 MO2

so in my config: i've planned to build  handmade PCB midi IIC module ... don't know the number... 6 outs will be right.

for my 2 x MIDI IO the second board (midi3/4) will be reserved for the BLM!

don't really have the necessity of the second MIDI IO board it must be the extra BLM components (of the IIC midi module from Smash TV) on a handmade pcb for leave some place in the box!

Are you agree?

so my midi config will be: 2 in / 8 out /  BLM port

Edited by tashikoma

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The BLM port is nothing else than a combined MIDI IN/OUT.

The QUAD IIC Board has already the required resistor and optocoupler components, so all you need to do is to connect one MI/MO pair + Vs + Vd from MIDI IO to the port to the Quad IIC Board

Best Regards, Thorsten.

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i finally understand that extra parts of BLM midi socket and the port on smashTV PCB was design for the old core STM32F1... so i will use just only one stage of the MIDI IO for the BLM purpose.
(sometimes it's like dumb n' dumber in my head)
thanks to all  ,thanks for support :angelnot:

so
3db08a8d-dd44-425c-aa56-a295f879ee75.jpg

Edited by tashikoma

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