MBSEQ V3.2 BPM 3 Digit Display Help

MIDIbox SEQ
1

!!!DONT PAY ATTENTION TO THIS THREAD AS I MADE A MISTAKE WITH MY DOUT BOARD. EVERYTHIGN HERE SHOULDN"T MATTER!!!

Hello everybody. I am trying to get the new 3 digit bpm leds to function on my soon to be finished SEQ 3.2. I follweed the diagram for this in the hardware options page. My question is do I need to connect vs to the common anode pins? I enabled bpm_digit display to #2 for common anode which is what mine is and reloaded the asm/hex to the core already. Also do I need to connect segments a-g to vs aswell? I have smash’s newest DOUT R3 board and have a-g wired to SR 5 and commons to SR 6. I removed my resistors from SR 6 for the common pins and left the resistors for ever other SR intact. I triple checked my wiring pin table for the display and believe my wiring is correct. Any help is appreciated. Here is my data sheet for the display attached.

[C4624JR.pdf](< base_url >/applications/core/interface/file/attachment.php?id=450)

[C4624JR.pdf](< base_url >/applications/core/interface/file/attachment.php?id=3592)

2

Hi,

no you don’t need to connect Vss or Vdd to any LED digit pins - in distance: if you would do this, you would fry the LEDs (-> dead) and maybe also the shift registers (-> dead)

You wrote that you’ve removed the resistors. Thats good - but did you also solder the bridges? In other words: did you replace the resistors by bridges, so that the common pins are directly connected to the 74HC595 outputs?

Another possibilty would be a failing .hex build, so that the old (unchanged) firmware has been uploaded - doublecheck that MPASMWIN doesn’t print an error message.

If you are unsure, you could also check this by opening main.inc, and replacing following message:

#define MBSEQ_VERSION_STR "MBSEQ V3.2a    "

by:

#define MBSEQ_VERSION_STR "Echopraxia      "

With this change, you should see your name after the MIOS bootscreen.

Best Regards, Thorsten.

3

Alright I soldered the bridges with some data wire and still I get nothing. The first time I had it hooked up I briefly got a flash of the g line when I turned off the sequencer. Did I break the display? I soldered data wire to bridge d4, d5 and d6 for common anode. I do not want the dot segment to be connected which is d7 on SR 5. I can leave this open right? Or do I have to connect it? On the data sheet It shows pin one to the very left when looking at the front and not the back. Then the pin order goes to the right and stops at pin 7 then to the top row starts at pin 8 where the order then goes right to left to end at pin 15 which is right above pin 1 on the display. I am reading the pin order correctly? Should MBSEQ 3.2 automatically turn on the display as soon as its powered up? I.E I don’t have to go to the tempo menu right?

4

And to reconfirm. I do not need to make any connections to ground on any of the segments and common anodes?

5

You are doing everything correctly, my assumption is, that there is anything wrong with the shift registers.

You are able to test each seperate pin with the dout_enc_v1_3 test, which is available at the MIOS download page.

When selected, the pin should output 5V, when not selected, 0V

Does it work?

To answer your other questions quickly: I cannot say if the display is broken, but if it flashes during power on, it seems to be ok. This effect tells you at least, that the 74HC595 are powered correctly.

Yes, dot LED doesn’t need to be connected.

Yes, the digits should display the BPM once the MIDIbox SEQ startup screen is visible after power-on.

No, you don’t need to go into the BPM page to activate the display, it’s a hardware option.

Display connections: always a confusing topic, it’s easier to try out the LEDs directly. Desolder the display, or remove the 74HC595 from the sockets and to the test by connecting cables to the empty socket pins. Connect ground over a 220 Ohm resistor to one of the cathodes, and +5V to a common anode line. The selected segment should lit.

Don’t forget the resistor - without you will fry the LEDs!

Note that it is also possible to do this test by connecting a resistor to the anode instead of cathode - it doesn’t matter when the resistor is located, it’s only important that you don’t drive the LED pins directly with 5V!

Best Regards, Thorsten.

6

lets say the pin out for the display was wired wrong. Then I possibly could have destroyed the display because the bridges without the resistor have been connected (maybe) to a segment and not to the common anode/cathode pins. I checked my wiring and I still belive it is correct but maybe this is what happened? I might try another brand and see what happens. I will also try the test you speak of and desolder the display and try to get at least one segment to work. Before I soldered the board I chipped/scraped off the copper track in between which two pins share. This needs to be done on veroboard correct?

7

I have finally uploaded the dout test program to see if a single led would light from any of the douts.  When you start the program it is on shift reg #1 and D0 0x00. I never changed this setting which should light only the led at SR#1 D0. I moved the led light to other D pins and the led still lit up on every other one. This shouldn’t happen right? I rewired J8 from the core with individual connectors to go straight to J1 on the DOUT because I thought this would better help me understand the routing of signals and noticed that only the outer pins on J1 of the DOUT can be used and the inner pins cannot be used. I am using Smash’s DOUT R3.