Orange imposters

I'm sure about it now. Seven of the LEDs above are orange. The rest are yellow. I've asked the supplier if I can get a replacemet set of yellow ones.

Flashing the EEPROM

In order that the MonomeSerial software 'sees' the monome clone, it's necessary to change the serial number of the arduino's EEPROM to resemble the serial number of a real monome.

I successfully followed Melka's instructions that have been posted on the bricktable blog (update: the bricktable blog instructions have been updated, you should follow those instructions rather than my version here).

You'll need access to a windows machine to complete this procedure, since the MProg software is windows only.

I'm going to paste his instructions here too (I hope that's not treading on anyone's toes), and include some of my own notes inbetween.

you have to install Mprog and the D2XX drivers from FTDI (your arduino will still work with the arduino IDE with this drivers)

MProg 3.0 > http://www.ftdichip.com/Resources/Utilities.htm
D2XX Drivers > http://www.ftdichip.com/Drivers/D2XX.htm

1/ Install both, then run Mprog

I installed the D2XX drivers on my winXP laptop first, following instructions in this PDF. This part requires you to have the arduino plugged into the PC via the usb cable. NB. while following these instructions the 'found hardware wizard' will run twice, this is normal, just point it to the directory that contains the drivers you downloaded both times.

I then installed Mprog on the same XP laptop, which was straightforward.

2/ Launch Mprog, then click on Device / Scan. You should see something like this appearing in the box down.
Code:

Number Of Blank Devices = 0
Number Of Programmed Devices = 1

3/ Click on Tools > Read and Parse. This will fill the boxes.
4/ Check the “use fixed serial number” box and change the value below.
To have your board recognized as a monome by monome serial, you have to enter something like
m40h-xxx (we used m40h-001)

I used the m40h-001 code too.

m64-xxxx
m128-xxx
m256-xxx
Choose whatever you want, I’m not sure what is different between the various IDs, for the moment I’m using m40h-001.
There is 2 protocols described on the monome site, and the 64/128/256 seems to be more complete (15 message IDs, 9 for the 40h protocol), so maybe you’d better use m256-xxx
5/ Click on File > save as
6/ Once saved, click on the flash icon (Program all existing devices, Ctrl+P).

It's the icon that looks like a lightening flash.

7/ Unplug / plug back your board from the usb port.

In my case, this meant unplugging the arduino's USB cable from my XP laptop and plugging it in to my macbook (where i have MonomeSerial installed).

8/ Run monomeserial, you should see something appear on the devices list.

You'll see the serial code you chose in the devices list (m40h-001).

Difficulty lighting a whole row

I've been adjusting the MAX test code, to gets the lights moving in different ways. While doing this I noticed that if a row is asked to light seven or eight of its LEDs at once, all the lights go out and I have to reset the arduino to get it going again. I'd like to find out why that is.

The button pad PCBs are all soldered up and all the components are in place in the breadboard version of the controller. To test that the MAX chip was working and wired up correctly, I uploaded this code to the arduino.

The MAX7219 has 'DIG' pins and 'SEG' pins, corresponding to the two axes of the LED matrix. The SEG pins supply voltage to the grid, and the DIG pins act as ground sinks. The SEG pins are named A to G and the eighth pin is called SEG DP. The DP pin should come first in the sequence, not last (the way I wired it first).

Once I'd corrected it, the example code gave the following pattern.



The difference between the two distinct colours of LED show up quite clearly (less so in the photo), that's a bit of a shame.

Button pad PCBs wired up

What's the best way to cleanly divide header strips?

The guy in my local electronics shop recommended that I just press in the notch with a knife. I tried it but wasn't able to snap them this way.



So I used a chisel and hammer. Which snapped them in the correct place, but a few times the casing to one of the sides of the break was damaged, sometimes losing a pin.

So what's a reliable way to cleanly break header strips like this into the lengths that you need?



Meanwhile, at Owen's suggestion I'm twisting wires together like this as a way of attaching two of them to a single via hole in the button pad PCBs (one wire is a jumper connecting the PCB to another one, the second wire leads to one of the shift registers or the max LED driver chip).

Misc parts

I got hold of a few more parts I needed.

The chip in the blue box is the MAX7219CNG LED driver.

There's a long strip of paired male headers. I'll snap this into four lengths of 16 pins.

The four black plastic things with female sockets are IDC connectors to attach to two ribbon cable lengths. I messed this up with the first one I tried and broke it, this time I'll use a vice to push down the part that cuts the cable. The IDC headers will plug into the paired header pin strips, forming a removable connection from the arduino shield PCB (at least I think I'll use a shield) to the button pad.

The things with pins are IC sockets. I'm using these so that I don't have to solder the chips directly to the PCBs, and can replace them easily if necessary. There are two 16 pin sockets for the shift registers, and one 24 pin socket for the max chip.