Looking for SBC with Heterogeneous Multicore Processor for Drone Development - Page 1
Forum section: electronics / projects

author: sidereal
author_rank: Contributor
timestamp: October 09, 2024, 01:13:39 am
content: Hello everyone,I’m looking for a recommendation on a single-board computer (SBC) that features a heterogeneous multicore processor suitable for drone applications. Here’s what we need:At least 4 cores in total, with 2 or more being real-time coresRISC -V core is preferred, ARM is okAbility to run Linux on the application cores and boot an RTOS on the real-time cores (Or propose alternative boot sequence)Not near the end of life, and with decent long-term supportIdeally an SBC (i.e. we do not have to create our own boards from scratch), with Analog and Digital GPIOWishful thinking: two ethernet ports (i.e. can act as a bridge) but is not necessaryLCD output greatly appreciated. 4K video,High definition and such not necessaryWishful thinking: On board Graphics acceleration, If available, should be accessible for GPU programming via a cuda like mechanismI came across people having success with Toradex and Sifive Unleashed. But I cant find detailed recipe to prepare everything and set up the boards like I wantAny suggestions for hardware that fits this description would be greatly appreciated! Thanks in advance!

author: brucehoult
author_rank: Super Contributor
timestamp: October 09, 2024, 01:41:11 am
content: If you're considering the HiFive Unleashed then presumably size and weight are not an issue.Also they only ever made about 500 of them and that was 2018 and it would be hard to find one. "Not near end of life". They were EOL five years ago.They also don't meet your "2+ real-time cores". There is one. I guess you could tell Linux to not use one or more of the four "applications processor" cores. You can ignore the FPU and MMU, but you probably can't disable the caches and branch predictor.If the SiFive 4+1 setup is acceptable to you then can get those exact cores, at a slightly slower 667 MHz clock speed, in the MicroSemi Polarfire SoC, complete with an FPGA fabric. An example new SBC with this that should be supported for a long time is the BeagleV "Fire" for $150.The just announced but not yet available Microchip PIC64 GX is also the same thing without the FPGA.But what about two (or more) Milk-V Duo? A 1 GHz Linux core and 700 MHz real-time core, both 64 bit. $3 with 64 MB RAM, $9.90 with 512 MB. *Extremely* small and light weight. The Linux core has a 128 bit vector processor supported by gcc 14 (asm, inline asm, C intrinsic functions).Or if you want something better than the Unleashed, there's the Milk-V Mars ($40 with 2 GB RAM) or Mars CM ($34). The five cores are all dual-issue vs single-issue in the Unleashed / PolarFire SoC / PIC64 / Duo and run at 1.5 GHz. The JH7110 in those (and the VisionFive 2 etc) is well documented, with a fully open source 3rd party boot process. You can program the whole thing bare metal if you want.The only thing I know of with 2+ real-time cores is the SG2380 which has 16 A78-class Linux SiFive OoO P670 cores with 128 bit vector units, plus 8 real-time SiFive X280 cores with 512 bit vector units (the same as NASA has selected for their next gen space probe CPU, replacing PPC750). But that's only just taped out and is probably a Q2 2025 thing.Well, the Pi Pico 2 has 2 real-time RISC-V cores, but no Linux cores.

author: sidereal
author_rank: Contributor
timestamp: October 09, 2024, 01:59:55 am
content: THANK YouI was not sure about MilkV but i will check.I should add: I need about 2 - 4GB RAM in the linux side, minimum 2GB. and I also need full gnu toolchain to run D, Pascal, Python, and if possible Julia on the linux side.Also, the number of Analog and Digital GPIO will be my final choice parameter. I did not list them at the main question, because i am still evaluating my payload options. But in general, 4 to 8 analog GPIO and 4 to 8 digital gpio, would be good. If there is audio in (that can work as analog in) and pwm out, that increases the device's value.I will investigate all the info you posted, but i will request, if you could also help me narrow down my choices among all the options you listed?Thanks again, really!

author: brucehoult
author_rank: Super Contributor
timestamp: October 09, 2024, 03:03:51 am
content: Number of analogue and digital IO in itself can't be a parameter, without specifying things such as speed and precision. There are external analogue chips with SPI/I2C and shift registers let you expand a couple of digital IO pins to as many as you want.For that matter, there are SPI RAM chips too.

author: sidereal
author_rank: Contributor
timestamp: October 09, 2024, 03:22:57 am
content: Right, I should be fine with 12 bit or better ADC. Speed : ima happy with 10 - 20 KHz .interrupt isnt necessary.But The SPI chip is a good idea. Thank You

author: Someone
author_rank: Super Contributor
timestamp: October 09, 2024, 03:58:54 am
content: Sounds an awful lot like a Xilinx MPSoC, they come in various form factors.