.:madworm:.'s photos

Now all that is missing is a bar of aluminium for mounting it under the cupboards in my kitchen. It should be 1200x40x5mm. All the stuff I can get at the hardware stores is either too short, too thin or too narrow...

One board is still missing, but its quite bright already.

The boards are actually quite purple.

I used my table top milling machine to remove some material. This avoids accidental shorting to the ground plane. Left one: using a small bit Right one: using a large bit, which saves time.

Saving pins by using an ADC channel to read 3 buttons is OK for just one board. But as soon as I connect two of them, the voltage levels are off. This was to be expected, as now two pullups are there, but even after removing one of them... doesn't work. The SMD resistors also vary quite a lot it seems. As I have another pin on the bus, I might later create some sort of message system to let the boards talk to each other (half duplex).

The final board. It takes about 8.5 to 10W, depending on the supply voltage. It is designed to run at 660mA. The LEDs are grouped in sets of 4, which requires about 12V to run at a high enough current. The LED driver takes about 0.7V off, so we're looking at a real 12.5V to 13V on the supply voltage connectors. Each group can be controlled individually, but currently all 8 channels are treated as one. The PWM is generated by a timer compare match interrupt. The data is sent via SPI to the LED driver.

I finally managed to capture the 'purple-ness' of the boards adequately.

This is what it looks like before the LED catastrophe. I had to remove 16 of them as something was shorting. I suspect that parts of the extremely wide pins (uses as heatsinks as well) were shorting to the ground plane somehow. I clipped them and partially ruined my wire cutter. It wasn't meant to cut such thick stuff. Only 64 more of these to go (LEDs not boards).

This is what it looks like before the LED catastrophe. I had to remove 16 of them as something was shorting. I suspect that parts of the extremely wide pins (uses as heatsinks as well) were shorting to the ground plane somehow. I clipped them and partially ruined my wire cutter. It wasn't meant to cut such thick stuff.

The purple colour of these boards seems to be totally incomprehensible for my scanner.

The purple colour of these boards seems to be totally incomprehensible for my scanner.

The purple colour of these boards seems to be totally incomprehensible for my scanner.

The purple colour of these boards seems to be totally incomprehensible for my scanner.

2 FRIGGIN' WEEKS !!!!! An airmail letter from the US takes 14 friggin' days to get to Germany. Where the heck do I live? Those damn customs guys really do hate me. I bet this letter has been sitting in some back office for the better of those 14 days.