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ESP32-S31

espressif.com

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Re: ESP32-S31

#121

Post by topspin »

PowerElectronix wrote: post #108
BenjiWiebe wrote: post #57

Earlier quoted context omitted.

Also why do you need 1uS for motor control? 1uS is 0.1 degrees of rotation at 16,666 RPM if I did the math right. I don't know much about motor control, is it normal to need that fast of feedback?

The closed loop experiences a phase margin loss that is exponential with the frequency. At lower frecuencies it is negligible, but if you get close to the frequency of the delay the phase margin reduction becomes dramatic and the control goes from stable to unstable very fast. If the sensor has a limited bandwidth, you add the conversion delay and then the computation delay on top of that you end up with a max workab…

You see this in low cost products like MKS SERVO42x, where they're doing FoC with a GD32 MCU. It works; the motor runs cool, smooth and quiet, but the system is limited to 3000 RPM, and struggles with rapid acceleration because the control loop is too slow.

Re: ESP32-S31

#122

Post by benj111 »

arabscum wrote: post #115
BenjiWiebe wrote: post #57

Earlier quoted context omitted.

Also why do you need 1uS for motor control? 1uS is 0.1 degrees of rotation at 16,666 RPM if I did the math right. I don't know much about motor control, is it normal to need that fast of feedback?

[flagged]

Have you never heard something that is surprising to you, and then asked for more information?

Well no. Probably not...

Re: ESP32-S31

#123

Post by numpad0 »

tliltocatl wrote: post #23
skybrian wrote: post #10

I'm interested in audio out because I dabble in musical instruments. What's the state of Bluetooth audio out on microcontrollers? Is low latency and high quality output possible?

Is there any reason you want wireless? Bluetooth audio is a disaster, AFAIK. You don't want to use it for music. Just go wired, the ether is too cramped already.

There aren't many choices of cheap hackable A2DP receivers if you were somehow looking for one. Not all headphone chips are programmed to run at slightly under 3.3V on VBAT pins so to protect the supposed battery, with no means to reprogram for lower voltages, officially or not.

Re: ESP32-S31

#124

Post by wildekek »

hart_russell wrote: post #26

Any reason why this device wouldn't have Z-Wave? Is the wireless protocol significantly different than Thread and Zigbee?

Z-Wave works on a different frequency and would separate radio hardware. And then comes the licensing cost.

Re: ESP32-S31

#126

Post by jamwise »

oritron wrote: post #18

The specs look great, will see how long it takes to get these as WROOM modules or on little dev boards; my two form factors of choice for Espressif devices. I'm also curious about the pricing, so far they've impressed me with how much more you get in successive generations at a similar price. If you're excited about the (relatively) speedy RISC-V cores and SIMD, look at the P4 which is available now. It has a slightl…

If the prices remain relatively similar this is going to be incredible value! I might have to procrastinate on my current side projects to go back to another side project I'm procrastinating on because of optimization issues on an older ESP32.

Re: ESP32-S31

#128

Post by snvzz »

NekkoDroid wrote: post #51
cassepipe wrote: post #35

Earlier quoted context omitted.

Thanks.I can't believe they chose non-arcane, memory-friendly letters. Kind of rare in naming hardware I feel (unless it's not ?)

I see you are unfamiliar with `rv64mafdcbvh_zicsr_zicntr_zihpm_ziccif_ziccrse_ziccrse_ziccamoa_zicclsm_za64rs_zihintpause_zic64b_zicbom_zicbop_zicboz_zfhmin_zkt_zihintntl_zicond_zimop_zcmop_zcb_zfa_zawrs_supm_svade_ssccptr_sstvecd_sstvala_sscounterenw_svpbmt_svinval_svnapot_sstc_sscofpmf_ssnpm_ssu64xl_sstateen_shcounterenw_shvstvala_shtvala_shvstvecd_shvsatpa_shgatpa` also known as `RVA23`

rva23 is pretty friendly.

Needn't use the long thing.

Re: ESP32-S31

#129

Post by polpo »

oritron wrote: post #18

The specs look great, will see how long it takes to get these as WROOM modules or on little dev boards; my two form factors of choice for Espressif devices. I'm also curious about the pricing, so far they've impressed me with how much more you get in successive generations at a similar price. If you're excited about the (relatively) speedy RISC-V cores and SIMD, look at the P4 which is available now. It has a slightl…

They've already released the ESP32-S31-WROOM-3 and two development boards based on it: the ESP32-S31-Function-CoreBoard-1 and ESP32-S31-Korvo-1. All are available on Espressif's official Aliexpress store.

Re: ESP32-S31

#130

Post by mrandish »

bobmcnamara wrote: post #94
mrandish wrote: post #69

Earlier quoted context omitted.

> I'm interested in audio out because I dabble in musical instruments. Sorry, I don't know. I'm just responding to echo and expand on another reply that Bluetooth for anything related to serious music, from audio playback to MIDI input is a dumpster fire on Windows. Several years ago I tried to set up a high-end Windows laptop for hobby DAW composition on the go. The real-world BT audio latency just from laptop to he…

I'll mention that you usually need to put the BT connection in a low latency audio profile or else you're likely to get something more suitable for mp3-style high buffer playback.

Thanks for the tip. I'm about to revisit this again soon (new laptop + some free time for fun). Have you been able to get BT latency low enough on Windows to hit a MIDI key and hear the note without noticeable lag?

It's been a few years since the last time I actually tried it myself, instead of just checking user reports. I do remember I followed the DAW company's FAQ, set a mode in the DAW, and switched something in Windows settings related to BT. The wired latency (MIDI in and audio out) was excellent but switching either to BT tanked it.

It's frustrating that it appears to not have improved at all in a decade. I get the whole "good, fast, cheap" triangle and that most of the BT ecosystem only cares about "cheap" while being just good enough 128Kbps MP3s don't sound too much worse on $50 cuff link-sized earbuds. But I can't help naively thinking that on decadal timescales, the rising tide should lift even the "cheapest" corner of the triangle enough to yield slightly better minimum baseline quality - especially when it's been stuck forever at barely usable. Even more surprising is that BT gaming controllers still have such high latency, most BT controllers also come with a proprietary wireless dongle. Talk about pointless COGS and landfill.

I guess maybe the reason is those who really care can go wired, use non-BT wireless dongles or lock themselves to a proprietary vendor who controls both ends of the stack. But it kind of nerfs the point of having a short range wireless "standard" if doesn't cut COGS, landfill waste and never improves more 'serious' use cases even a little.

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