arox

From an end user point of view, a command like h3disp (for example h3power) with use case profiles would be usefull. Of course, it should use specific tables for the board and would be complex to define, test and parameter. I am not sure that dynamic handling of number of active cores should be a priority, because that depends itself of use cases and then it seems somewhat complex and needing numerous tests but others may think otherwise. (For me, who use cards for specifc functions, it is easy to know how many cores I can use. Number of servers in network or IO services can be a bottleneck in case of full load, but it principally concerns shared usage and do seldom apply to domestic cases). What is NanoPi Air ? Is there a platform targeted at BT audio server (it would make sense to disable internal DAC because of software complexity or instability in BT/a2dp/alsa/pulseaudio). I am a bit lost with nanopi : multiple sites, old cards that would I would have be interested in but no more to sale (?), payment threw PayPal, lot of accessories, serious support and documentation (compared to Orange Pi) but frantic new products release ?

Well, (bad) SSD (may) need 5W on active state. (what about init, journal replay or fsck). When running on battery, the idle state consumption is what import. But one have to be cautious about how it is powered. I power mine directly (not threw the card).

By the way, if you have a look at the specs, an SSD need 5W on active state !

Does it work with other wannabe "cutting edge" debian distros for arm ? I ask this because I had a hard time to install wireshark on gentoo on a headless system, because it requires gtk+, which requires opengl, witch requires mesa, witch requires llvm, witch wont compile and is perfectly unnecesseary for mali driver (if I understand well).

pezi said ! "The sink has the same size like the SBC!" I hate noise. 12 years ago, I assembled an AMD Athlon with (almost) passive cooling. The heat sink costed me more than a powerfull arm card : a copper block with large fan-shape wings, the size of one of our favorite cards, and 5 centimeters high. It was assembled with silver paste and tithlty pressed on the proc ... There is no miracle : if you want to reach high frequencies without a noisy fan wich increase air pressure on the heatsink, you need a costly (copper) and big (air contact surface) heatsink. But I think I nevertheless I will buy a small aluminium heatsink to improve things for my desktop device.

mmcblk01 ? or mmcblk0p1

At least you have to change root in bootargs from mmcblk0p1 to sda1 in /boot/boot.cmd and do an "mkimage" as specified at end of file. The kernel is on SD card and will be newer, so you will need to update modules and headers, by upgrading with apt if you can boot on sata or by copying /lib/modules/<kernel version> and /usr/src/linux-headers-<kernel version>

A quick test show that I can spare 150 mW by downgrading ethernet to 100 Mbits - witch is not surprising. (ethtool -s eth0 speed 100 duplex full). Modern switchs boast having adaptative power (with port usage and wire length). I use currently a 10 meters cable and will check the difference when I moved the swith and use shorter cable. But I dont expect a difference for BPI m2+ as the power consumption does not lower at idle when I unplug the cable.

I asked because I never could power the card threw the jack entry, even by soldering 0.75 mm2 wires. But it could be the other end USB-A contacts, bad soldering, my card or the PSU ... or a design problem in the PCB ? If I had been prepared to face such stupid problem (by reading more carefully this forum) before I ordered the card, I would have also ordered an (other) industrial PSU with screw bornier and adjustable voltage (like MeanWell SNT RS 15 5). I power 3 cards, relays, HDD and other things flawlessly with one of those (and cannot use it for tests !).

Yes, my BPI m2+ has exactly the same problem. Could you say us if you managed to power it by micro-usb or barrel plug ?

"switched also DRAM clockspeed between 432 MHz and 624 MHz ..." Have you made stress test with reduced DRAM clockspeed ? My BPI M2+ entered in a total instability state while compiling large packages ending up with system freezing. Even with reduced CPU clockspeed and number of cores - not a CPU heating problem. The symptoms disappeared when I reseted original DRAM clockspeed. Could it be a problem of eMMC calibration ? (I'll make other tests with io activity trace and reduce DRAM speed when I eventually manage to get *!@? wireshark running on gentoo)

If you have electronics skills, you can easily make a hat with an MCP3002 (https://www.sparkfun.com/products/8636 2.3$) : 10 bits 2 channels SPI ADC. (I had tested a MCP3208 (12bits 8 channels) but the two last bits there noise.)

Well bad idee : sound cards seem to have a condo in input and cannot mesure DC.

When my scope died 3 years ago, I had a look at xoscope. Audio cards have a 16 bits adc and so must have an A20 card ? By the way, one for the mic and another with 2 chans on the camera connector. (I have to get a flat cable to check audio input, because it is almost impossible to solder on card). I had bought a dozen of metal resistor to make a shunt but never found the time to check it and lost my calcualtions about current mesurement, impedance and input limit on audio cards. With 10 1 ohm resistors in parallel, and 1 amp current, the 0,1 ohm shunt should take 0,1 W and 100 mV on power line. And I should be able to calibrate and mesure transcient and average current at 20 kHz. (I also checked an SPI ADC on RPI - easy to wire on a test board - the problem was then the noise level).

"Simply try it out" Well, question of priority ! I will have a look at longsleep project because a virtualizer is one of my architecture targets. I just found the sale page for pine64. Money is not a big deal when you compare to the time spent in trying to make it work (with people that pretends it is working - I have a long list). I donot understand how you manage to do so much, but I am new to armbian and a bit lost in the mass of information. Thanks a lot one more time : you saved my skin many times with uboot or /sys/ info or little things like op_mode=2 for bcmdhd.

tkaiser said : "Apart from that 64-bit ARM systems can be pretty fast." I am a bit at a loss. What is for exemple the state of the art with Odroid C2. Am I right to say that there is no today any distro that can use userspace programs and libraries (like firefox) compiled for 64 bits arm ? And at the end, how much is the performance/heat dissipation ratio better (which determine the usability for a passive cooling small card system) ?

They propose to ship it with unsoldered USB-A and ETH connector : good, it will be the smaller and lighter card on the market !

Well, parallelizing boot script or making it dependant of network is a bad idee, because it tends to make it unpredictable. Especially when some init process depends on clock and the RTC dont keep time if you unplug power supply ...

@tkaiser Thanks a lot. I spared another 200 mW and 3° ! I can now run my "gatekeeper" with less than 2W (no video, 2 cpu) - initially more than 5W with an (untuned) RPI-B with outdated software. Benchmarking performance in real world for my use case is not so easy and I have to think of a method. The usage is interactive (text filtering by privoxy) and the final result depends from network, and complex pipelining. I already found in first test that cpufreq governor parameters were optimal in armbian. Energy saving (and heat dissipation) is a complex matter anyway but not so important during winter ! As a matter of fact, I spare 20W by shutting down my ISP TV box and audio booster with relays, and I can spare much more by driving intelligently my central heating circulator. I would like to have humidity sensors everywhere in the house because a leakage can cost you up to 1000 times the cost of a card if you dont detect it. So my next project will be to find the best card for IOT projects, even if I must downgrade performance of a 4 core, 1,5 GHz, 1Go RAM card - as manufacturers are not so much interested in providing cheap and light solutions.

Hi, I found I could spare 300 mW and 3° at idle by disabling 2 cpu, but I dont have any change by setting dram_clk = 480 in dram_para in script.bin. Did I miss something ? (BPI M2+ 3.4.112-sun8i #8 SMP PREEMPT Mon Jun 20 12:54:33 CEST 2016 armv7l ARMv7 Processor rev 5 (v7l) sun8i GNU/Linux stock kernel)

I'm not sure 64 bits systems are of any interest, and I dont feel like installing a virtualization system on a arm card. Is that possible anyway ?

well, thats a good question anyway. But, how do you save and archive your Windows system, your ISP Box HD, your phone, your micro-oven firmware ? The systens are today [auto]-updated more rapidly than you can do full archive of modified system. The caches grows and sature your disks, the system can break anytime due to updates. Progressive archives are not easy to manage and resoring is even more difficult So if you dont do anything usefull with it, there is no point to save or archive anything. If you store document, media, program sources, do it in user directory or a network share and save it every day. If you spend days or month on a project, then reject updates, archive the installed system, the boot block and part table (1st Mb of SD card), the insallation image, acquire hardware replacement parts and document in electronic and paper format every single hardware and software step necessary to restore your project when it will crash in 3 years and you will have completely forgotten how it could work. If someone has a better answer (excluding the installation of a noisy rack of Terabytes disks - and daily work), I am interested.

"Different people, different needs!" Well, my first Unix workstation was a microVax (Digital Equipment). One tiny mips and it ran X11 ! My new H3 BPI boasts : SMP: Total of 4 processors activated (19200.00 BogoMIPS) LOL I should say my new BPI M2+ is not the best card I ever saw, but eMMC is very valuable. It replaces now a RPI-B as firewall/gateway with 10 times cpu power and IO bandwith but with half the consumption (2 Ethernet - GbE + USB, wifi, Bluetooth, no display = 2,5 W - PSU has 75% efficiency). The (2nd level) http proxy cache can now run on the gateway thanks to eMMC). I will test DRAM lower frequency after reinstalling the mail gateways.

"Unfortunately not with H3 boards." If I anderstand well, H3 boards have no voltage monitoring hardware. So I should find an external hardware solution. How do you retrieve PMU stats ? Perhaps could you power an A20 board threw an H3 device to check power stability ? Thanks for your works anyway : I got the first usable distro for BPI-m1 as desktop with armbian (ubuntu) and my bpi m2+ will be ready for production in a few days as firewall/gateway/ap (customized gentoo with armbian kernel/uboot) N.B. I use ap62xx for wifi and external dongle for bt since bluez is (one more time) buggy - in order to use external adapter, disabling bt in script.bin is necessary.

Perhaps a schmitt trigger and a LED on 5V GPIO ?