**** BEGIN LOGGING AT Mon Dec 12 02:59:57 2022 Dec 12 12:25:46 Hi all, developing a custom beagle bone board (based on OSD3358-512M-BSM) to make it fiber-ethernet ready. Most of my questions are already sorted out. What I'm currently fiddling with is the eMMC. Never had one in my designs. Question is what to consider when selecting it (there are tons with the distributors). Size, clock-rate, ... Special Dec 12 12:25:46 (in)-compatibilities with the OSD3358...? Dec 12 13:02:30 OP: mainly just size and price... there might also be variations in performance and/or reliability features (e.g. SMART-like monitoring) Dec 12 13:04:18 Thanks zmatt. Took BeagleBoneBlack as reference and it has a 4GB Kingston which is not available. Is 4GB a sensible value then? 32 is common what I see and acceptable in price. Dec 12 13:05:23 OP: that's up to you and your application... we only use about half a gig of space on our production devices Dec 12 13:06:40 How much the operational system will use from the eMMC (a common debian)? Dec 12 13:07:08 that doesn't have an answer, it's completely dependent on what you're going to install on it or use it for Dec 12 13:07:21 Sure. Dec 12 13:08:32 Not planing to store any data. Using network mounts here. It is basically the default debian running Python scripts. Nothing more. Dec 12 13:09:19 even "default" depends on what image you use... the iot image needs a fair bit of space because it's crammed full of crap that may be of use to some users Dec 12 13:12:13 OK. So just for OS and applications I should be safe with 32G I guess then. With our prototype we used a BBBlack with a debian image around 3GB in size when I recall correctly. Some apps installed already. Dec 12 13:12:39 32G sounds like an excessive amount of space, but if that's the cheapest you can find then sure Dec 12 13:15:17 Kay, thanks! Dec 12 13:15:17 Regarding the power supply. I see the OSD3358-512M-BSM can be operated by a supply as low as 3.7V. Unfortunately not lower (3.3V) right? Dec 12 14:07:57 OP: tps65217 recommends a supply of 4.3-5.8V, if you're going to use USB it should be 4.75-5.25V (i.e. 5V ±5%) Dec 12 14:12:08 unless you mean VIN_BAT, which is for a li-ion/lipo cell specifically (not just any random power supply) Dec 12 14:12:37 and 3.7V is not its minimum... I'm not sure what the minimum is, at some point the 3.3V supplies will start to lose regulation Dec 12 14:14:18 if you do intend to run from a battery, beware that it comes with a bunch of caveats (e.g. the SYS_VDD1_3P3V of the OSD3358-SM should not be used in that case) Dec 12 14:15:19 I was referring to the VIN_BAT pin. We did some experiments with that pin. I remember the chip needed AC/USB power to boot but could later be switched to the BAT power. Guess we will need to go with AC/USB then. Dec 12 14:16:09 Could not get it working properly. Dec 12 14:16:16 it doesn't need AC/USB to boot, but you do need to press the power button to power on if on BAT only Dec 12 14:18:08 and if both BAT and AC/USB are present it will try to charge the battery via BAT Dec 12 14:18:12 It needed a edge there, you are right! Dec 12 14:18:17 It needed an edge there, you are right! Dec 12 14:18:58 This would have need to be emulated then (so the button press). Dec 12 14:20:14 also beware that BAT remains connected to SYS_5V even while the device is powered off Dec 12 14:20:31 Yes, thanks! Dec 12 14:20:38 and again, do not use SYS_VDD1_3P3V for anything if you're using BAT Dec 12 14:20:53 and of course USB will not work and should be disabled in DT Dec 12 14:21:25 (USB host port I mean) Dec 12 15:01:13 With the power manager on the BBBlack there was another issue. It's default settings (which could not be changed) was to have a lower voltage threshold of something around 3.5V (on the VIN_BAT). This setting could be change during runtime but would fall back on a power cycle (volatile). Dec 12 15:09:43 Thats why we could not boot it with 3.3V on VIN_BAT. Dec 12 16:29:45 3.3V on VBAT would also result in the 3.3V supplies being out of regulation, resulting in potential stability issues Dec 12 16:30:35 you're not going to get 3.3V out of an LDO when you supply it with 3.3V on its input Dec 12 16:31:16 it'll just turn into a resistor, resulting in voltage fluctuations as the current draw varies Dec 12 23:20:16 -Wall is a miracle w/ the BBB! Dec 12 23:20:36 I was having a set_ moment. Luckily, www. Dec 12 23:22:19 Hey, I think you guys handled the pwm functionality in a file somewhere on the BBB. I say this b/c I see the polarity and enable is already located on the BBB in /dev/pwm/ but the sysfs files are there too, e.g. w/out me making the files available. Dec 12 23:23:12 I never gave up on making PWM work. For instance, I know it works. It does. But...in .c files along w/ a .h or many .c files, it takes some research. Dec 12 23:23:28 I think...blah. Dec 12 23:24:19 I mean...blah. Did someone already make the pwm functionality available on the BBB w/ kernel 4.19.x and 5.10.x so people do not bug you all about it? Dec 12 23:25:01 I ask b/c it is way more interesting than once thought... at first, it was a hassle. Now, it is totally awesome! Dec 12 23:26:18 See. i have a dislocated mindset here, i.e. as I do/did not know of this fact being real. I just thought it was a given. NOt so! Dec 12 23:31:33 sometimes w/ the sysfs interface, things need to be allocated to it in userspace or even beforehand like w/ the images available. Dec 12 23:34:52 Hello? Dec 12 23:49:58 It is me... Dec 12 23:50:06 * set_ says hey you! Dec 13 01:52:58 Could anyone here help me with a Debian install? Dec 13 02:05:47 me, me, me! Dec 13 02:06:07 etcher Dec 13 02:06:41 stick in the SD Card to the host. Use etcher, once etcher finishes. Take it out of the host. Stick it in the target. BBB! Dec 13 02:12:36 Let me find the link to look over. Dec 13 02:14:05 This is a start. Just use the forum to get your Bullseye image install instead of the /latest-images page at beagleboard.org. Dec 13 02:14:13 Oh and here: https://beagleboard.org/getting-started Dec 13 02:54:06 Is cheese here? Dec 13 02:54:26 Forget it. Nope. Dec 13 02:56:00 If cheese shows up, please someone alarm me! **** ENDING LOGGING AT Tue Dec 13 02:59:56 2022