Tempo indicator for PT2399 based delays

[GP]

Sorry for dragging up an old thread but i was hoping someone (Andre?) maybe still had the schematics that Andre posted.

The only thing I can find is Cathexis' layout which has confused me no end since he has commented that it only seems to work with the ground disconnected - how can it work at all if there's no ground?

[alex frias]

1+

[Andre]

I have the schematic on a network drive that's defective at the moment.
As soon as it's fixed i will re-post it.

BTW. the first version was not too accurate.
The second version that uses a 12F675 PIC processor is very accurate but has an audible tick.

However, the schematic, sourcecode and hexcode of this version are also on the defective networkdrive, so give me some time to have this drive fixed.

[GP]

I'm not too worried about accuracy as such... i was really just using this as an example of dividing down a clock frequency but i don't really undertstand how i should go about doing this.

Anyway, i was trying to understand how i should AND bits together to produce a non base-2 division. I know how to implement a discrete AND gate but, when i combine two bits together, i'm not getting the result i expect. I'm not sure where i should connect the Reset pin - to ground or to the result of the AND? If i connect to ground, i don't get what i expect and, if i connect to the result, i don't get anything.

Cathexis' layout makes no sense to me since, as i see it, it simply sends the 1/1024 output to the second 4040 and the result of the AND isn't going where i would expect it to go. On top of this, i'm really confused as to how it can work if the ground is disconnected! Surely, no ground = no operating CMOS chips?

[Andre]

I'm not too worried about accuracy as such... i was really just using this as an example of dividing down a clock frequency but i don't really undertstand how i should go about doing this.

Anyway, i was trying to understand how i should AND bits together to produce a non base-2 division. I know how to implement a discrete AND gate but, when i combine two bits together, i'm not getting the result i expect. I'm not sure where i should connect the Reset pin - to ground or to the result of the AND? If i connect to ground, i don't get what i expect and, if i connect to the result, i don't get anything.

Cathexis' layout makes no sense to me since, as i see it, it simply sends the 1/1024 output to the second 4040 and the result of the AND isn't going where i would expect it to go. On top of this, i'm really confused as to how it can work if the ground is disconnected! Surely, no ground = no operating CMOS chips?

I hope my ascii art shows normal (it does in the preview) , but this is the principle I used:

                         +
                         |
                          \
                          /   10k
                          \
   4040                /
  ______             |
  |     Q0|___|/|__|
  |         |     |\|    |
  |         |             |
  |     Q1|___|/|__|
  |         |     |\|    |
  |         |             |
  |     Q2|_           |
  |         |             |
  |         |             |
  |     Q3|_._ |/|__|   
  |         |  |   |\|   |
  |         |  |_____|_____ out
  |      R |_______|
  |_____|   

I think I first  calculated the binary equivalent of twice the dividend I wanted.
Then I connected diodes to the corresponding 4040 outputs like in the example and took the output from the most significant output.
Maybe you can experiment a bit with this circuit to get the output you want.

[GP]

Thanks a lot for taking the time to reply, Andre... and the ascii makes enough sense to me to answer my issues. I think my biggest problem was getting my head around using the MSB for the output. It seems counterintuitive (like this is equal to the reduced clock that's being sent onward) but now i see that the output clock speed is always going to be influenced by how often you reset the counter.

I'd searched and searched all of last night and there aren't really many examples of combining bits to make a tailored division. I guess this is probably because there are better chips to use for a non base-2 number (i.e programmable, synchronous counters). Anyway, i have a couple of 74hct4020s and i wanted to see if i can do something interesting with the pt2399's clock but NOT tap tempo.

[aneeshprasobhan]

well, there is absolutely no schematic that is live now. Really sad....Does anyone have the tempo led schematics ?  And would it work with HCF4040BE?

[slacker]

There's a vero layout for it here http://www.diystompboxes.com/smfforum/index.php?topic=102660.0 this is basically as good as a schematic. It should work with any 4040 chip.