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Dingoo A330

Posted 2010.05.31 20.26 in Computers/Internet/Technology

It’s the new release from Dingoo Technologies. I got one to satisfy my curiosity, but sadly it disappoints on many levels.

Dingoo A330

I made up a new version of Dingux that takes advantage of the added memory and faster clock speed. To do that, I needed to get a serial port in there for testing. Unlike the A320, the 330 seems to just have half a port; TX but no RX. So you can get debug data out, but you can’t interact with it. Sucky.

Probing for the RX Line

The TX data is found on a single unmarked testpoint that lies beneath the LCD screen, in the upper middle part of the motherboard. In hopes of finding the RX line, I did some probing to the copper traces around the CPU in the area of the TX line, but neither of my two most-promising candidates proved to be RX data. It is probably not connected at all. More sucky.

A330 Motherboard

I stuck the serial port on the left-hand side of the Dingoo, above the reset button. It was the only clear spot on the motherboard, but it turns out the left speaker wants to sit there, and the serial port keeps failing on me – I have to take it apart and fiddle with it to get it working again. The A330 disappoints on many levels.

Dingoo Serial Port Step-by-Step

Posted 2010.05.26 10.05 in Computers/Internet/Technology

I added another serial port to another Dingoo and this time I took pics of the process all along the way.

Click the thumbnails for enlarged images and details.

Cheers!

P.s. I forgot to publish this earlier, sorry for the delay.

Pointless Dingoo Mods – Redux

Posted 2010.05.07 8.50 in Computers/Internet/Technology

Not long ago I did some pointless mods to my Dingoo game device. I added a power LED and a good old fashioned serial port. I called them pointless because the LED just tells you it’s on, and usually you can tell that from other hints. As for the serial port, at the time I put it in, I didn’t even have a way to connect to it, so that was even more pointless. At the time.

Since then, I’ve ended up using the serial port quite a bit – I had an FTDI prototype chip in my parts bin, and made a USB to Serial converter to connect the port on my Dingoo, then installed Minicom on my linux laptop. This has come in handy a few times as I’ve been hacking around with the linux kernel and trying to learn more about the boot sequence. I’ve baffed up the Dingoo a few times such that the serial port was the only way to access it.

As for the LED, when I wired it in originally I just connected it directly between Vcc and Ground. The LED is rated for 3.2 to 3.5 vdc; the battery in the Dingoo is rated at 3.7v nominally. I’ve seen its output as high as 4v though. Needless to say, the blue LED was fried in only a matter of days. Ooops.

So I had to go back in again tonight, and while I was replacing the blue LED (and adding a resistor to limit the current) I took a couple pics.

Pointless Dingoo Mods

Posted 2010.04.22 9.44 in Computers/Internet/Technology

Last night I was a bit bored so I sat down and did some pointless hardware mods to my Dingoo.

First, I added a power LED. When the backlight is off, or if you boot it with the B button to go into flashing mode, it’s hard to know if the Dingoo is on or off. And in any event, I’m a sucker for LEDs. “Real electronics should glow in the dark.”

The easy part was attaching the LED, I used a surface mount blue LED that draws 10mA at 3.6v and stuck it near the start button, then wired it between Vcc and ground. I found a point on the rear of the board where the power is switched so I just ran a bit of 28 gauge wire around from the back to the front. The hard part was getting a hole in the black layer of the front case, without also going through the clear part of the front case. I used a cheap soldering iron to melt some of the plastic then some small precision chisels to cut out the plastic and get the hole to be just about right. Actually it was about 80% luck, I’m usually not this good at modifying the plastic parts.

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