LEO LEO Vertical LEDs

[ronnyjamesdisco]

With an external reset cable connected to VRESET/RESETIN1 jack U5 will be counting to 10 while not receiving an external reset trigger (since the plugged jack breaks the normalled SELVRESET signal).

The vertical LEDs light up going down 4 ticks, then stay unlit for another 6 ticks until U5 - CD4017 counts up to 10 to restart from 1 again.

U4 - CD4024 counts binary in powers of 2 so the mix CV outs appear to loop through ABCD / DCBA.

As a result the vertical LEDs will show the wrong steps after the 6 blind ticks.

One possible fix is grabbing the SELVRESET signal from the nc switching terminal of the reset jack and sum it with RESETIN1 through a 1K resistor at R6 on the control PCB.

That way both counters stay in line but still follow external resets.
I haven´t tested this with linked Leo Leo modules so I can´t tell if there would be an issue.

[andybutler]

Nice fix.
I used a diode instead of the 1K.
There also needs to be a diode added to the 4017 . Anode on pin 10 (5th step, Q4), cathode on pin 15 (reset).
If we ignore the longer divisions which aren't used the 4024 is always running 00 01 10 11 in a 4 step cycle even if it doesn't get a reset.
The 4017 gets a reset every time the 4024 does, so they only go out of sync if the 4024 goes back to zero without a reset. With the diode the 4017 can only go 12341234...so now it's locked to the 4024.

I've not tested with a second module, but logically that's a fix.

[ronnyjamesdisco]

Oh yeah, that looks like an elegant solution!
The way I had it didn't work with linked units and for now I just fed a clock divider to the reset. Didn't think that was already built in ;) will give it a try next time I'm at my workshop.