Make:

Looks perfect for restoring/emulating pinball games...

This source comes with no mention of a license. Additionally, the source for the Windows service ( u-disp_sw_1.0_src.zip) contains nothing but a JPEG of some lady who seems to be on vacation!

Hi, I'm the project designer.

There seems to be a major SNAFU with the source zip. The file there was a test that I did when creating the site, and my old brain forgot about putting up the real file before launch. I bet my wife is really glad that it was a "decent" pic of her :-) And no, we're not on vacation, is a pic of her outside the Dubai Creek Golf Club a couple of minutes from our apartment.

Anyhow, the licenses are BSD - Do what you like with is as long as copyright notices are left intact. I'll update the site with it.

This is my first project with a "high visibility" factor, please bear with my mistakes.... I'm sure there are a lot of missing information and stuff.

I like the way the boards stack side-by-side with the serial connections linking up. That's good design. I have a bunch of LED displays here (and loads of 10-LED bargraph displays); might have a go at something similar.

Two comments:

a) Watch your current consumption. It doesn't look like you tell the OS that your device is a "high power" device (meaning it draws more than 100 mA after enumeration). You might find that it simply won't work, or works intermittently, on some computer's USB ports or on bus-powered hub ports. Thems the breaks of violating the USB specs, I guess.

b) Instead of the hacky USB-to-RS232 chip hooked to the micro, you could've used an SiLabs C8051F320 which includes a USB interface. Choose HID as the device class (so you don't need to write a driver) and define a simple report containing the string to display. SiLabs has excellent app notes and firmware to get you started.

Andy,

a) The FT232R-chip that I'm using is set to report itself as a high power device that wants 500 mA. Still, a single display draws about 110 mA so it would (more or less) work even without the high power setting. The u-disp is violating the suspend mode max of 0.5 mA though.

b) Come again? The FT232R is "hacky"? It's a fourth generation highly USB-to-Serial chip from FTDI having internal clockgenerator & eeprom (no external components needed) as well as a unique serialnumber for sequrity applications. Win XP have built in drivers for it and it reports as a virtual com-port.

I like the AVR architecture, much more than for instance PIC. Is the C8051F320 like the old 8051 that I've used 15 years ago? I really don't feel to learn yet another microcontroller now, my brain is getting older for each day, and I have enough trouble going from PHP/C/C# in my different projects.... :-)

Yeah you gotta watch out for clever clogs, they're everywhere.

Nice work Mats - well impressed!

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