IRC #olimex 2015-05-15

[15:08:54] <viccuad> guys, what do you recommend as a Realtime Clock Module for an Olimex Olinuxino Lime with a case, so it fits inside? thanks in advance
[15:10:38] <lukas2511> onlinuxino lime already has a realtime clock
[15:11:45] <viccuad> well
[15:12:15] <viccuad> I need want with an external battery, I'm using it as an air-gapped computer, and it gets powered off from time to time
[15:12:27] <viccuad> s/need want/need one
[15:12:59] <lukas2511> if you attach a battery to the lime and shut it down it should keep the rtc running
[15:13:28] <viccuad> mmmmh..
[15:13:33] <viccuad> lukas2511: thanks
[15:14:36] <lukas2511> other then that you could look for those cheap DS1307 modules, which are I2C, should be relatively easy to attach
[15:16:32] <viccuad> lukas2511: do you know how much that battery will last, more or less, with a powered off A20 Olinuxino Lime and a 1500mA battery? does it power off CPU, etc, or it's just in nop state yet running everything?
[15:19:38] <lukas2511> if you shut it down it should actually be off, the axp209 (which also contains the rtc) should power everything off except itself
[15:20:50] <viccuad> lukas2511: thanks
[17:04:24] <viccuad> Guys, how can I know if a battery is charging in an A20 Olinuxino?
[17:16:13] <viccuad> Does it support "hot plugging the battery"? switching from the 3.7 lipo battery to the 5v Olimex connector?
[17:41:20] <lukas2511> viccuad: ?
[17:41:51] <lukas2511> you can see somewhere in /sys/class/power_supply, there should be something like "battery" or so, and that should have a uevent file which will contain all information about the current state of the battery
[17:46:09] <viccuad> lukas2511: thanks. Although that dir is empty. Should I have a kernel module or smth?
[17:46:33] <lukas2511> uh, do you have mainline or sunxi kernel?
[17:47:55] <viccuad> lukas2511: mainline, 3.19.1-1, debian one from their repos
[17:49:57] <lukas2511> yeaaa mainline is a bit of a problem right now i think
[17:50:51] <lukas2511> there is currently a patch on the mailinglist, but it is not supported right now
[17:53:01] <lukas2511> so if you want mainline you probably want to use a DS1307 module with its own battery... I2C has been merged in 3.13, so that should work.
[17:54:08] <lukas2511> i guess you could also use olimex mod-rtc with the corresponding adapter for the lime
[17:57:43] <viccuad> lukas2511: uh. that makes sense. thanks.
[20:42:57] <lanodan> Is there a high latency on the SATA port ? (I’m considering buying a SSD because it’s light but solid)
[20:45:13] <lanodan> (For A20-OLinuXino-LIME2-4G)
[20:47:09] <adj_> lanodan, allwinner sata is slow ~80MB/s reading ~40MB/s writing
[20:47:57] <adj_> I don't know about latency, but I suppose that latency is not much slower than sata in other platforms
[20:52:20] <lanodan> 80MB and 40MB is still better than USB xD
[20:57:17] <adj_> yes, much better than usb 2.0
[20:57:33] <adj_> and also much better than sd or internal flash
[21:21:47] <lanodan> Is there open-source drives ? (open-hardware would be great)
[22:23:37] <Turl> lanodan: what would make a drive open source?
[22:23:57] <Turl> they're hardware devices