New Crowdfunding Campaign Offers Modular EOMA68 Computing Devices (crowdsupply.com)

A new crowdfunding campaign by Rhombus Tech "introduces the world's first devices built around the EOMA68 standard," which separates a "modular" CPU board from the rest of the system so that it can be easily used in multiple devices and upgraded more simply. Rhombus Tech is now offering a 15.6-inch laptop, a laser-cut wooden Micro-Desktop housing, and two types of computer cards, both using A20 dual-core ARM Cortex A7 processors. The cards are available with four flavors of the GNU/Linux operating system, and they're hoping to receive RYF certification from the Free Software Foundation.

"No proprietary software," explains their campaign's video. "No backdoors. No spyware. No NDAs." They envision a world where users upgrade their computers by simply popping in a new card -- reducing electronic waste -- or print new laptop casings to repair defects or swap in different colors. (And they also hope to eventually see the cards also working with cameras, phones, tablets, and gaming consoles.) Rhombus Tech CTO Luke Leighton did a Slashdot interview in 2012, and contacted Slashdot this weekend to announce: A live-streamed video from Hope2016 explains what it's about, and there is a huge range of discussions and articles online. The real burning question is: if a single Software Libre Engineer can teach themselves PCB design and bring modular computing to people on the budget available from a single company, why are there not already a huge number of companies doing modular upgradeable hardware?

Comments

Because.se one size does not fit all

[zemned3000]

The reason that this isn't already a common approach in the industry is that forcing constraints on form factors for SoC devices has some intractable issues. If you have a powerful SoC it demands high power and needs to dissipate heat; so the upper bound of what you can achieve in the packaging and with the connector will be rapidly met u.nless it is massively over specified, and then it will be large and expensive. Also, display technology is not fixed in time, parallel interface signals are already quite out of date as an interface specification , although the actual limit here will probably be down to the PCMCIA connectors impedance discontinuity and consistency after numerous insertions when more modern differential display protocols are adopted. It is a laudable aim, but I doubt this will save the planet from computer waste.

Re:Because.se one size does not fit all

[lkcl]

The reason that this isn't already a common approach in the industry is that forcing constraints on form factors for SoC devices has some intractable issues. If you have a powerful SoC it demands high power and needs to dissipate heat; so the upper bound of what you can achieve in the packaging and with the connector will be rapidly met u.nless it is massively over specified, and then it will be large and expensive.

we're dealing with that by setting a hard limit for the [re-used, pin-incompatible] PCMCIA "Type I" and "Type II" sockets which are 3.3mm and 5.0mm respectively: the hard limit for these two thinner card types is 5.0 watts. so at around 3.0 to 3.5 watts there's still absolutely no need for fans or any kind of special thermal considerations: passive cooling is all that's needed, and the SoC happens to be in contact with the stainless steel case, which happens to be in contact with the aluminium of the keyboard (in the case of the laptop).

just over that (up to 4.0 watts) and it is possible to use exactly the same graphite paper that's been developed for mobile phones. cheap, readily-available.

at around 4.5 watts it would be necessary to seal the package and flood it with thermal gel.

Also, display technology is not fixed in time, parallel interface signals are already quite out of date as an interface specification , although the actual limit here will probably be down to the PCMCIA connectors impedance discontinuity and consistency after numerous insertions when more modern differential display protocols are adopted. .

right. i spent five years analysing this and the impedance of PCMCIA (which, again, just to emphasise, we are *NOT* electrically or electronically compatible with: EOMA68 merely REUSES the PCMCIA connectors, housings, sockets and assemblies) is 100 ohms.

the EOMA68 standard uses RGB/TTL because that allows you to go all the way from 320x240 up to 1366x768 which works out to be around 80mhz. 80mhz over 100 ohm impedance is just about acceptable: you remember those "gold shields" on PCMCIA? those were designed to reduce EMI. the cards we're using for the initial prototypes have the metal case covering the entire connector, both sides.

why use RGB/TTL? this is covered in the eco-computing white paper in detail, section on "interface selection" http://rhombus-tech.net/whitep... basically if you consider the cost of 320x240 LCDs and take a look on http://panelook.com/ they're peanuts cost and they're *all* RGB/TTL. if you added a converter IC it would be a massively-disproportionate percentage addition to the BOM. however if you go up to a 1024x600 which costs $18 approx and you add a $1 SN75LVDS83b LVDS converter IC.... that's not so bad, is it?