arm-netbook November 2015

arm-netbook@lists.phcomp.co.uk

15 participants
11 discussions

qualcom snapdragon 410
by Luke Kenneth Casson Leighton 28 Nov '15

28 Nov '15

> [*] https://developer.qualcomm.com/hardware/dragonboard-410c > > ("Free graphics possible" according to the Debian Wiki's ARM 64 port page... > > https://wiki.debian.org/Arm64Port Adreno GPU. niiiice. minimalist hardware datasheet (with pinouts but not mechanical layout) on arrow electronics, as well as a five THOUSAND page datasheet on the hardware registers. this might actually qualify as an FSF-Endorseable processor, and, with a bit of work, might actually be a great candidate for an EOMA68 CPU Card. it will need a MIPI-to-RGB/TTL converter IC on-board. there's I2C, UART, SPI, 2 SDCs (one is eMMC, the other is SD/MMC), only one USB port (bleeeergh!), which means that a USB Hub IC is needed.. so we're looking at... whatever the SoC cost is (knowing qualcomm they'll want around the $12 mark for it), plus USB Hub IC and components ($1.50), plus a MIPI-to-RGB/TTL converter IC (could be as high as $2.50), so we'd be looking at what.... $15.... ... and the allwinner A64 we know is only $5. with 2 USB interfaces, RGB/TTL output.... whyy, god, whyyyyy... :) l.

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laptop power board
by Luke Kenneth Casson Leighton 28 Nov '15

28 Nov '15

.... i have the LTC 4155 15W power IC as well as the STC3115 battery monitor ICs recognised on the I2C bus with 5V power applied, yippeee. embarrassingly, i had the 5V DC socket wired reverse-polarity. this is, uhh, an officially-sanctioned test of the reverse-voltage protection on the power board design. no, really :) on a 2nd (minimally-populated) board i have the 5V regulated output up, but not on the fully-populated board. what i'll do is fill in all the components from the minimally-populated board, testing it as i go along. i'm looking forward to _not_ setting fire to the apartment when i plug in the e-bike lithium battery. unlike many of these "laptop" batteries it has no current protection circuit built-in, and it's perfectly capable of delivering 20 amps maximum current :) l.

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The $5 Raspberry Pi Zero is out
by joem 27 Nov '15

27 Nov '15

The $5 Raspberry Pi is out https://www.raspberrypi.org/blog/raspberry-pi-zero/ All sold out everywhere in hours :(

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laptop main board, power board and ingenic jz4775 cpu card
by Luke Kenneth Casson Leighton 26 Nov '15

26 Nov '15

ok, been quite busy, 3 to 4 different things going on. first one: i've been working on getting the eoma68-a20 board up and running (booting) out of NAND flash, that's been quite hair-raising. using a sunxi 3.15-10-rc5 kernel i was able to use the standard mtd-tools package to erase and write to the hynix TSOP48 NAND chip, placing an SPL-enabled recent version of u-boot onto it. this all worked fine... except it turns out that MLC NAND can self-destruct just by reading! all i can say is, no wonder allwinner's bootloader process is so damn complex! it's like a 4-stage boot: boot0 (minimum bring-up), boot1 (capable of reading NAND as well as SD/MMC FAT partitions), then u-boot (modified to read allwinner's strange partition format) and finally linux kernel. second, the jz4775 CPU Card is finally underway: http://rhombus-tech.net/ingenic/jz4775/news/ this is the first FSF-Endorseable CPU Card, using the 1.2ghz low-power Ingenic MIPS. it seems strange to put a $3 processor alongside $2.50 of NAND Flash and then put in almost $12 of DDR3 RAM ICs (2 GB RAM) but the threshold where SoCs were no longer the most expensive part of a BOM was passed a loong time ago. third, the laptop main board, i've got everything working except the LCD. i've blown up 2 LCDs already, it was necessary to buy 2 more. first mistake was that it was hard to read the datasheet so the connector was reversed: that resulted in -20V being shoved up the backside of the +3.3v sensitive ICs on the LCD, end result when i was finally able to make up a reversed-cable, the "magic smoke" left that LCD. also i hadn't noticed that i'd shorted the 5V rail to the 3.3v rail, which didn't help, and may have damaged some of the GPIOs on one of the EOMA68-A20 boards i have here. still quite a bit to investigate there. fourth, i've managed to smoke about 3-4 Power ICs already - various MOSFETs, two 3 Amp RT8288 PMICs from microdesktop boards i'm using for test purposes - all to get the laptop power / charger board up and running. annoying! but finally a couple of hours ago, by making up a 2nd board with minimal components, i managed to get the LTC4155 up and recognised on the I2C bus, as well as check that it was outputting stable 5V from USB-style input. the next phase is to populate the over-voltage and reverse-voltage protection components. it's getting there... it's just slower than i would like. l.

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laptop power PCB working!
by Luke Kenneth Casson Leighton 26 Nov '15

26 Nov '15

yaaaaa, i have battery-operation, i am currently running an eoma68-a20 off of a 10Ah e-bike battery, and both the LTC4155 charger/dual-supply IC and the ST3115 battery guage IC are up and recogniseable on the I2C bus. i have yet to compile up the linux kernel modules for both these devices, but they are both available... somewhere :) only slight issue to track down: power drops to 4V when the 5V DC is plugged in, i still have to investigate that, but it may be related to the setting of 3A input and i only have a 2A 5V charger. i can change the settings, and i can also "ping" the LTC4155 over the I2C bus... maybe :) but.... progress, yay! l.

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Cool Recycled Laptop Bag for EOMA-68 Laptop?
by Alexander Stephen Thomas Ross 23 Nov '15

23 Nov '15

http://www.protecttheplanet.co.uk/terracycle/denim-messenger-bag.html i look the look of it. made from scrap denim. I’d say looks the part for a laptop bag to sell/go with a eoma-* laptop. I wonder how the sew the scraps together? machine or cheap/slave labour?

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LVDS and HDMI to the same time
by Martin von Kameke 20 Nov '15

20 Nov '15

Hi, It is possible to use lvds and hdmi to the same time? I will display the same picture. Best regards, Martin

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Turris Omnia FLOSS Router
by Alexander Stephen Thomas Ross 16 Nov '15

16 Nov '15

https://omnia.turris.cz/en/ thoughts? there’s one comment on the indiegogo page about the wifi chipsets there looking at using depending on sourcing. not sure that it will be completely free software (inc (ie wifi)firmware & driver). they don’t say what is definition of the "lifetime of the device" is, regarding updates for it? 2 years or 10? ###### I’m looking to get a decent, free software router. come to think of it what about the eome-68 router? When eoma-68 isn’t going to have Ethernet?

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Jetson TX1 Module
by GaCuest 13 Nov '15

13 Nov '15

Maybe this is interesting for EOMA-68... http://www.nvidia.com/object/jetson-tx1-module.html

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The A64-OLinuXino laptop idea
by Paul Boddie 11 Nov '15

11 Nov '15

Hello, I see that Luke's friends/rivals at Olimex are considering the idea of a laptop based on their "64-bit" development board: "A64-OLinuXino OSHW 64-bit ARM DIY Laptop idea update" https://olimex.wordpress.com/2015/11/05/a64-olinuxino-oshw-64-bit-arm-diy- laptop-idea-update/ Their blog post about the board: "We work on A64-OLinuXino the first Open Source Hardware 64-bit development board" https://olimex.wordpress.com/2015/10/16/we-work-on-a64-olinuxino-the-first- open-source-hardware-64-bit-development-board/ The baffling thing about this "64-bit ARM" stuff, apart from the apparent lack of vendor cooperation for Linux kernel development... "One of the problem is that A64 is quite new and no any Linux-Sunxi support, as nobody have seen A64 development boards yet. SO it may pass several months until A64-OLinuXino run anything else than Android 5.1" ...is that the principal benefit of bringing "64-bit" to ARM - addressing more than 2GB RAM - is absent from this design. Indeed, I've only seen one ARM- based board - and not even a "64-bit" one [1] - which had 4GB RAM, let alone more than that. And I imagine that the 4GB RAM is divided between the cores on that Freescale i.MX6 board. (From what I've heard, Freescale is somewhat better than Allwinner with regard to support and documentation, contrary to claims in comments on the Olimex blog.) Anyway, I thought this was worth a quick perusal. Paul [1] http://solid-run.com/freescale-imx6-family/hummingboard/hummingboard- specifications/

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arm-netbook November 2015