Diezel Herbert Footswitch

[Jonathan Wilder]

This is a thread showcasing the next project I'm currently working on for George Lynch. The problem with the Diezel Herbert heads is that for some reason, they didn't install a provision for a regular analog foot switch so it can only be switched with a MIDI controller. Well, like lots of us, George likes to keep things simple. So he's called upon me to design/build a simple foot switch that plugs into the MIDI In port.

The foot switch I've designed will have 7 buttons on it and each one will have a unique MIDI CC controller number assigned to it. It will not be programmable...the CC numbers will be internally "hard coded" in software to the switch. The CC numbers will match the CC numbers that are assigned to each MIDI switchable function within the Herbert.

The chassis blank and switches for it came in today. Managed to get the button switch/LED holes center punched/pilot drilled, then final drilled the switch holes. Here is a pic with the switches temporarily mounted -

 

[NewReligion]

Very Cool Jon. I am happy to see the relationship continue. Rock on.

David

 

[Alabama Thunderpussy]

Good stuff Jon. Unfortunately I wasn't able to make it over to Badsteben this past week to talk Peter out of a Herbert or a Hagen, so I will have to wait until I manage to win the Lottery before I can afford one and have you make a footswitch for it.

 

[bennieusmaximus]

Mabey you can get some backstage groopies outa this.

 

[Jonathan Wilder]

LOL.

Good news. I bread boarded the circuit yesterday and today. Worked out the indicator LED routines yesterday, then assembled the foot switch array and MIDI Out driver circuit. Took me a few hours to fully debug, but the code is fully debugged and I was able to implement some additional functionality that defaults the functions on the amp to a given default on/off setting when the controller powers up.

So it's ready to be assembled now.

However, I still have to go through Diezel's code to add in the ability for the amp to respond to CC messages as they took that functionality out years ago. That'll be the fun part of this entire project. They were kind enough to send me a replacement microcontroller along with the binary files that get burned into the chip, which I was successful at disassembling.

 

[MartyStrat54]

Get it on, Jon!

 

[diesect20022000]

NICE! congrats on the ongoing working relationship man. Very happy for you

 

[Jonathan Wilder]

Here's an updated shot of the Herbert/VH4 digital foot switch -

As it turns out, I don't have to modify Diezel's code at all. They implemented individual function switching through the MIDI port, however it violates the MIDI specification as it uses program change data values that are higher than 127 so a standard MIDI foot controller cannot call up the required programs to access these functions. However, since my foot switch is being made exclusive to the Herbert and VH4, the messages it sends out do not have to conform to the MIDI specification even though the hardware and the interfacing of it follows the MIDI specification to a T. So this controller will send out the required data values to access the individual function switching in their code.

 

[mike mike]

That's awesome Jon. Cool stuff. Maybe I'll get one of those If I ever get a Herbert some day, which I do plan on doing.