Category Archives: Firmware

Broken Links

Due to a change made by DropBox, a number of the links on this site to user manuals and software have been broken. I am fixing these as quickly as possible so I would ask you to be patient while I do this.

Update: I’ve been through all the links and hopefully all have been fixed 🙂

If you find any other broken links please do post a comment below to let me know.

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New ‘Firmware Update’ Feature in Librarian

In part prompted by the lack of a Mac OS version of an app to upload firmware revisions to the EchoTapper and Blue Nebula effects units, I decided to add this feature to the Blue Nebula Librarian and also to update the older EchoTapper (eTap2HW) Librarian.

This now means that users of both Windows and Apple Mac OSX computers can update their firmware in both effects units without needing to use a third-party app such as XLoader, which in any case was only available for Windows :-).

Blue Nebula Librarian beginning with Version 4.00 and EchoTapper Librarian from Version 3.00 include this very useful feature and you can download them now from the ‘Latest Updates Here’ link in the menu bar above.

Note to Mac Users: you will need to download and install the Arduino IDE in Applications. Don’t worry, you don’t have to understand it our even need to run it but it contains an application that is required by the Librarian. Windows users do not require the Arduino IDE.

Both Windows and Mac require the Java Runtime Environment (JRE) Version 8 or above to be installed. If you don’t already have it – if Librarian is working you DO have the JRE 🙂 – click here and choose the version of the JRE for your operating system.

Blue Nebula Librarian 4.00

Blue Nebula Librarian 4.00

 

EchoTapper Librarian 3.00

EchoTapper Librarian 3.00

When a firmware update is released the first step is to download and unzip it (if necessary) to your computer from this website and make a note of where you saved it (by default it is usually saved in the Downloads folder). Now connect your Blue Nebula or EchoTapper  to the computer via the USB cable and choose the Serial Port that it is connected to in the usual way. Click the red Firmware Update button at the bottom of the Librarian window and a file browser will open to allow you to locate the file you downloaded previously.

Select the correct file (it will have a .hex extension) and click Open. Depending on the speed of your computer the update takes about 15-30 seconds after which the Blue Nebula/EchoTapper will restart. As your effects unit displays its Welcome screen, you can check that it now shows the version number of the updated firmware to confirm the update has been successful.

Please note that the firmware update ‘disconnects’ the effect unit from the computer’s serial port so if you wish to continue using the Librarian after an update you need to click the Re-scan button and reselect the Serial Port to re-establish contact with the Blue Nebula/EchoTapper.

The Journey Continues

“Bilbo saw that the moment had come when he must do something.”
― J.R.R. Tolkien, The Hobbit

 Chapter 2

As I explained in Chapter 1, while being very pleased with the sound of my newly constructed eTap2hw echo box I really wanted a way to store some settings for the tunes I played regularly.

My previous echo machine had been a Zoom RFX2000 with the EFTP programs from Charlie Hall. These programs or patches were numbered from 0-42 on the Zoom’s two digit seven-segment display and they came with a list of suggested patches for the common tunes by The Shadows.

IMG_3855_1296

The Zoom RFX2000 displays two-digit preset numbers

Having been able to compare the sound of the RFX2000, which I had been previously pretty happy with, to the warmer and more ‘analog’ sounding eTap2hw, I decided to try to add the ability to store the settings for the tunes to the eTap2hw so I could recall them easily. The Zoom RFX2000 still required you to either remember or look up the patch number in a printed list of tunes.

My original short ‘wish list’ was something along the lines of:

  1. Ability to name patches, for example “Apache” or “Wonderful Land”.
  2. Be able to adjust the effect parameters by using real knobs,
  3. and store and recall these settings easily.
To which I added, as possible future additions:
  1. Interface via USB with a computer for backing up and restoring patches
  2. Addition of MIDI control to select patches, possibly by using a MIDI foot controller or by sending program change messages from a sequencer playing the backing track.

About this time I discovered some forum postings by a guy in the USA called Johan Forrer who had come up with a design for the automation circuit and had produced a simple version of the software to drive it, for the Arduino platform. When I got in touch with Johan he very kindly and with no hesitation, sent me the source code for his automation.

eTap2hw-Automation 014

One of Johan Forrer’s early prototypes with basic automation from October 2012.

Having studied his code I quickly realised it wouldn’t fulfil my basic requirement of being able to name the patches to match the tunes: he had allowed for 8 presets (basically one for each of the 8 emulations in Piet’s SKRM-eTap2hw module) and only four user patches which could not be named, only referred to by number. Each could use any of the 8 emulation presets and you could set the values of the three parameters of each by hitting the up and down buttons but there was no provision for setting the parameters with real knobs.

Johan’s code did, however, have the basic structure that would be needed so, with his permission, I started to ‘hack’ it and add the features I’d planned. First though I needed the hardware on which to run the automation and, whilst Johan had built his own Atmel Arduino-like microcontroller circuit I decided to go for an off the shelf Arduino Uno and an LCD/Buttons shield kit from Adafruit.

The latter would be more or less essential to leave enough free inputs and outputs on the Arduino to satisfy my ambitious plans. As it connects to the Arduino via the I2C bus, it required only two input/output lines to operate both the LCD and the buttons, rather than the more normal parallel LCD drive which needs up to seven of the Arduino’s precious digital pins.

In the manual eTap2hw design the three parameter pots are connected directly to the SKRM module’s P0, P1 and P2 inputs. These each provide  a variable DC voltage between 0 and 3.3V that is read by the DSP code running on the FV-1 chip on the module and can used to alter the parameters, depending on what the code has been designed to do. Piet’s eTap2hw code mainly used P0 to control the mix of wet and dry signal, P1 was a program or ‘heads’ control which usually emulated the heads switch on the Meazzi and Vox echo machines and P2 was usually controlling the feedback or ‘repeats’ of the echoes.

To automate the system these pots had to be disconnected from the echo module and instead the voltages they were outputting would be read by three analog inputs on the Arduino. As the Arduino operates at 5V logic levels and the FV-1 operates at 3.3V logic levels, the pots would have to be wired to GND and +5V rather than +3.3V and some sort of interface would be needed to drop the Arduino’s ‘analog’ outputs to a 0 – 3.3V range.

The P0, P1 and P2 inputs on the echo module would now be driven by dc voltages output from the Arduino. A complication was that the Arduino’s analog outputs are not true analog DC voltages. Instead they use a system of pulse width modulation (PWM) to generate the output and not a true DC voltage – the wider the pulse the higher the average voltage:

Johan and Piet together had already solved these two problems by coming up with a low-pass filter combined with a voltage divider that would both smooth the PWM to give true DC and at the same time reduce it from 5V max to 3.3V max. You can see one of these on the left hand end of the breadboard in the following photo of my first test-bed prototype.

IMG_6873_5503

My first bread-boarded automation test-bed. January 2013

The blue trimmer pot on the right is connected to an analog input pin on the Arduino and the LCD is showing which button was last pressed and the analog input value being read from the pot wiper. The buttons board assembly which I built on Veroboard actually ended up being used in my first completed Echotapper Vintage Echo Unit – until the buttons wore out!

At this point Piet came up with a great little design for a shield that would do all the interfacing between the Arduino, the pots and the SKRM-eTap2hw echo module.He called it the Universal I/O Shield and it certainly simplified the wiring required as it would stack on top of the Arduino and the LCD shield would stack on top of that. The only wiring required would be to the external pots, the eTap2hw motherboard and the 12V dc power supply.

The Universal I/O shield takes care of all the PWM filtering and logic level shifting between the Arduino and the echo module.

IMG_6923_5567

The Universal I/O Shield stacked on top of the Arduino Uno.

Having proved my ideas were going to be feasible I continued to develop the software for the automation, which I’ll refer to as firmware from now on to avoid any confusion with any software possibly running on the PC.

In parallel with the firmware development I looked for a suitable enclosure that could house the project and after much deliberation, measurement and ‘guesstimating’ I settled on a Hammond 1455N2201 Extruded Aluminium Enclosure measuring 223 x 103 x 53mm. As you’ll see below, it was quite a squeeze to fit it all in!

The finished unit turned out very well and I even managed to include the MIDI control that had been on the ‘nice but maybe later’ wish-list.

IMG_6946_5590

The Automation Version Completed – January 2013

Word had begun to get around and this project seemed to be generating a good bit of interest from The Shadows forums. Steve Mitchell, who would come to play an important role in the Blue Nebula Team, was probably the first builder to take on the task of emulating my efforts. As he says himself

I eventually got into the Automated eTap2HW after managing to contact Piet who kindly pointed me in the direction of Newtone. Then I realised that there was also an Arduino based automation, which Piet was supporting with his interface shield PCB. So I contacted Johan, Lars and yourself and it went from there when I decided to “bite the bullet” and go for broke without ever building a manual version. Once I’d purchased the interface from Piet then off I went now firmly attached to your “Journey”.

Though doing a few things a little differently, such as using a larger enclosure  (good decision Steve!), by April 2013 Steve had become the proud owner of another eTap2HW plus automation or, as he called it on his excellent front panel, his “EchoTapper Vintage Echoes of the Sixties.”

eTap2build-USB-SCM

eTap2build-SCM

The Finished Project by Steve Mitchell

While working with Steve and helping him with his project we formed a close working relationship and soon Steve was coming up with some great suggestions for improving the firmware and some clever ideas to get an even better sound out of Piet’s analog preamp design – but that will have to wait for Chapter 3!

Librarian and Blue Nebula Version 3.0

The release Version 3.0 of the Blue Nebula firmware and the matching Librarian app Version 3.0 are undergoing final testing and will be released here shortly.

Librarian V3 Screenshot

A quick glance at the new Librarian User Guide (link below) will show you the many interesting features and how it works with the Blue Nebula to give a really unique and exciting new effect pedal experience.

Briefly, the Librarian app allows you to transfer your patches between the Blue Nebula and your computer and it allows you to back them up by saving onto the computer – but it does a LOT more!

It also allows you to edit your patches, for example renaming them or tweaking the parameters, as well as having copy and paste functions and it allows you to create set lists so you can have the tunes arranged in the order you want for a show. The up and down footswitches then allow you to step through the list with the LCD display showing you the name of each tune.

The Blue Nebula comes with 8 vintage echo effects already installed in its first memory chip (MEM 1) but the new Librarian’s biggest and most unique feature is probably its ability to upload another 8 effects via USB to the second memory chip (MEM 2). This updates the effect and parameter names on both the Blue Nebula pedal and in the Librarian app which will recall them next time it’s run so that it always stays in sync with the effects on-board the pedal.

These additional 8 effects can be chosen from a wide range to standard guitar effects that are already available on the internet – many free DSP programs are listed on the Spin Semiconductors website. In addition there are several unique new effects that the Blue Nebula design team is currently working on and we will be making these available (also free) ready to upload to the Blue Nebula via the USB input.

‘Standard’ effects include popular guitar effects including chorus, phaser, flanger, delays and reverbs and the new effects currently in development include emulations of the classic Binson Echorec and an enhanced Vox Long Tom emulation.

User Guide for Librarian Version 3.0 (pdf)

Latest Versions Page Updated

I realized that the version of Firmware 3.30 I posted on the updates page was compiled for a MONO LCD so those who have gone to the expense of fitting an RGB LCD were not getting the benefit so I’ve added a new Version 3.30 compiled for RGB LCDs. You can download all the latest firmware and software by clicking on the ‘Latest Updates Here’ link in the banner above.

The RGB display uses some different screen colours to indicate the different modes that your eTap2HW is operating in. For example:

Setting-MIDI-Channel IMG_7101_7086_edited-1 Advanced-Editing-(pots)

Firmware Update 3.30

These updates are like buses, none for ages then two come along at once! This one features a nice little improvement to the Manual Mode display suggested by Rolf Holmberg. It now shows the function of each of the three pots so you don’t need to remember what each one does. For anyone not familiar with the eTap2HW effects designed by Piet Verbruggen, the function of the three controls can vary depending on which echo model you have selected. Click on the ‘Latest Updates Here’ link in the menu bar at the top of the page.

The new display is shown in this quick little video I made. Video

LCD – Common Anode or Common Cathode?

It has come to my attention recently that there are some LCD display modules on sale that are ‘Common Cathode’ types (e.g. this one from SparkFun) , rather than the more common ‘Common Anode’ type (e.g. this one from Adafruit).

Why would you care about this?

Because the two types of display essentially operate with ‘inverted’ logic signals relative to each other, you will probably find that your LCD display is very dark after you upload the ‘wrong’ Automation code. Essentially the ‘common cathode’ type is insisting that white is black and black is white – just like some people we know!

If you’re got an RGB display then all the other colours will not appear as intended either and they won’t match what’s stated in the User Guide.

As a result I’m now providing two versions of the Automation code on the Updates page so make sure you use the correct one for your LCD type.

If, after uploading, your screen is very dark then try the other version.

A handy feature I’ve added to the code (thanks to Eric Thacker for prompting me to implement it), the unit now ‘remembers’ the last preset or user patch that you used and starts up with this when it’s next switched on, rather than always defaulting to Preset 0: Apache. This is actually very convenient if there is a favourite patch you use a lot 🙂