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BBAI-64 released?
My regular BBAI just arrived from mouser three days ago, and now I see there's a 64-bit version? With a DC barrel and what looks to be a ginormous heatsink? Maybe mouser will accept returns.....
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Images in first link on this page: https://beagleboard.org/ai-64/press
System reference manual: https://git.beagleboard.org/beagleboard/beaglebone-ai-64/-/blob/main/doc/SRM/BeagleBone_AI-64_System_Reference_Manual.adoc
Annoying that there is absolutely no mention (that I could find) of any cooling requirements. Is it designed to be free-air cooled? Does it require a minimal airflow from a fan? 5V @ 3A is 15 watts which is not trivial. Especially not in any closed container.
For comparison:
Okay, so I've ordered one of these.
In case it isn't obvious, don't go buying these things yet expecting them to work with the current Kiwi software release. It is quite likely some new software support will be required. Particularly GPIO differences as we saw between the BBG/BBB (TI AM3359 cpu) and the BBAI (TI AM5729 cpu). The BBAI-64 uses the TI TDA4VM cpu. Just go grep the sources for
CPU_AM5729andBBAIto see what was required last time with the BBAI.The current rev B1 schematics are here: BeagleBone_AI-64_Rev_B1_SCH_220602.pdf Page 29 shown a 5V fan power header connector. With fan tach/pwm control signals that connect to GPIOs on the processor. So these are likely meant for die temperature plus software-based fan speed control, although I'd bet no software support has been implemented yet.
Fun fact: The TDA4VM data sheet is 232 pages. The silicon errata is 70 pages. The technical reference manual, with all register descriptions, is 23701 pages (not a typo -- 23.7k!) FML..
Wow, that's a long datasheet! OK about not buying one for now, from an ease-of-use perspective it seems like a winner though. No homebrew cooling solution or linear power supply to USB-C adapter needed, that's super nice.
It might not need a USB-C adapter, but most existing solutions for linear 5V supplies (or the low-noise 12V-5V DC/DC solution) max out at ~3A, and now you need a total of 5-6A for the KiwiSDR + AI-64. Or am I missing something here? That'll require some consideration.
The input 5V should definitely be fed via the 2.1/5.5 mm DC jack on the AI-64. Have a look at the schematic page 29 (kiwisdr.com/files/BeagleBone_AI-64_Rev_B1_SCH_220602.pdf) The power mux chip (TPS2121) has an output current limit of 4.94A set by R16 = 20k. In a pinch that can be increased to 5.4A with R16 = 18k, but that's the maximum (see the TPS2121 data sheet).
Since a lot of the gates on the AI-64 will never be switched in the Kiwi application it's likely this will not be an issue. Note that 5V to the Kiwi is fed from VSYS_5V0 on the right side (switched) of the TPS2121 and with 3.3V from a regulator downstream from there.
The Kiwi board ran on the AI64 for the first time today. After a month of difficult work due to many factors, including the preliminary state of the AI64 software.
Even though it works in principle it will take more time before I can simplify and automate the installation procedure so it (hopefully) isn't any more complicated than the instructions were for the BeagleBone AI.
I haven't had time to do any measurements of any kind. But of course things feel a lot faster as you'd expect. Whether it's a worthwhile investment/upgrade or not is still unknown.
I'm hoping you are successful with this effort. I have three Kiwis, but have shied away from the BBAI because it looked to me as if it may be more trouble than it's worth, at least to this CLI-phobic guy. But it sure would be nice to have the additional channels.