BGA soldering

Making A One-Of-A-Kind Lime2 SBC

Upgrading RAM on most computers is often quite a straightforward task: look up the supported modules, purchase them, push a couple of levers, remove the old, and install the new. However, this project submitted by [Mads Chr. Olesen] is anything but a simple.

In this project, he sets out to double the RAM on a Olimex A20-OLinuXino-LIME2 single-board computer. The Lime2 came with 1 GB of RAM soldered to the board, but he knew the A20 processor could support more and wondered if simply swapping RAM chips could double the capacity. He documents the process of selecting the candidate RAM chip for the swap and walks us through how U-Boot determines the amount of memory present in the system.

While your desktop likely has RAM on removable sticks, the RAM here is soldered to the board. Swapping the chip required learning a new skill: BGA soldering, a non-trivial technique to master. Initially, the soldering didn’t go as planned, requiring extra steps to resolve issues. After reworking the soldering, he successfully installed both new chips. The moment of truth arrived—he booted up the LIME2, and it worked! He now owns the only LIME2 with 2 GB of RAM.

Be sure to check out some other BGA soldering projects we’ve featured over the years.

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Hackaday Links: July 7, 2024

Begun, the Spectrum Wars have. First, it was AM radio getting the shaft (last item) and being yanked out of cars for the supposed impossibility of peaceful coexistence with rolling broadband EMI generators EVs. That battle has gone back and forth for the last year or two here in the US, with lawmakers even getting involved at one point (first item) by threatening legislation to make terrestrial AM radio available in every car sold. We’re honestly not sure where it stands now in the US, but now the Swiss seem to be entering the fray a little up the dial by turning off all their analog FM broadcasts at the end of the year. This doesn’t seem to be related to interference — after all, no static at all — but more from the standpoint of reclaiming spectrum that’s no longer turning a profit. There are apparently very few analog FM receivers in use in Switzerland anymore, with everyone having switched to DAB+ or streaming to get their music fix, and keeping FM transmitters on the air isn’t cheap, so the numbers are just stacked against the analog stations. It’s hard to say if this is a portent of things to come in other parts of the world, but it certainly doesn’t bode well for the overall health of terrestrial broadcasting. “First they came for AM radio, and I did nothing because I’m not old enough to listen to AM radio. But then they came for analog FM radio, and when I lost my album-oriented classic rock station, I realized that I’m actually old enough for AM.”

Continue reading “Hackaday Links: July 7, 2024”

DOOM On A Desk Phone Is Just The Tip Of The Iceberg

These days we expect even the cheapest of burner smartphones to feature a multi-core processor, at least a gigabyte of RAM, and a Linux-based operating system. But obviously those sort of specs are unnecessary for an old school POTS desktop phone. Well, that’s what we thought. Then [Josh Max] wrote in to tell us about his adventures in hacking the CaptionCall, and now we’re eager to see what the community can do with root access on a surprisingly powerful Linux phone.

As the names implies, the CaptionCall is a desk phone with an LCD above the keypad that shows real-time captions. Anyone in the United States with hearing loss can get one of these phones for free from the government, so naturally they sell for peanuts on the second hand market. Well, at least they did. Then [Josh] had to go ahead and crack the root password for the ARMv7 i.MX6 powered phone, started poking around inside of its 4 GB of onboard NAND, and got the thing running DOOM.