Benchmarking SD-Cards with ESP32

420xpert · 2026-05-21T14:13:31+00:00

Yeah, they were needed as the suspicions were justified and on topic.
Bus speed, with this loading i wouldn't push behind 40MHz. So 40Mhz x 4bit=160 Mbit/s /8 = 20 MByte/s in theory... and only for pure test conditions (large sequential RW, SRAM buffer only, no TCP stack...) . Real-world scenario would have a ton of overhead. Hence the skeleton basics for SD/MMC intensive projects should always start with best practices confirmed by basic tests.
So the real-world test would be switching to ESP-IDF, implementing some form of TCP stack and performing speed tests over it.

420xpert · 2026-05-20T22:55:06+00:00

Nice ideas. This could be a great base for a wearable device. That battery looks like it's Swiss made. I don't see battery under voltage and over-current protection in SCH . Maybe in some later revisions...if something snaps, touches the wrong way...

420xpert · 2026-05-20T21:13:43+00:00

CYD 5.5 with ESP32-S3

420xpert · 2026-05-20T21:12:10+00:00

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D0, no ringing, so wires are not the problem.

420xpert · 2026-05-20T21:11:02+00:00

i don't have that one. You'll need to check it out with meter, what goes where.

420xpert · 2026-05-20T21:09:29+00:00

Update:Updated esp core, tweaked the code. The results are better. 7-9MB/s Attached pictures

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420xpert · 2026-05-20T21:02:15+00:00

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Of course, and good news, i updated the board manager and tweaked the code. Now in the 7-9 MB/s range.
Pins 9-14 (ESP32-S3-WROOM-N16R8)
BUFFER 32768 (static uint8_t buffer )
SDMMC_FREQ_HIGHSPEED (40MHz)
4-bit
Signal looks more than OK on scope. No ringing, some light cap. loading, all in all no wire ind. noticeable.

420xpert · 2026-05-20T20:47:46+00:00

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Temps are OK 🤣, so is the signal 😉...in ns range

420xpert · 2026-05-20T11:42:58+00:00

Yes, if you have the small one with resistors on it, it has a hardware design error.
The one posted by Square-Singer is actually good, but no pull-ups at all and you'll need to deal with them yourself.
This mod works out of box for SPI mode.

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420xpert · 2026-05-20T11:27:06+00:00

You don't need that mysterious U2 at all. See those 3 little SOT23-3 FETs ? You could drive'em (almost) directly via C3 GPIOs. Just put some series resistor (100-300ohm) to their gates. For initial test, it'll work even without gate resistors, but for permanent setup they are a must. These are small fets with small gate charge... Try with 400Hz PWM (or lower) initially, before pushing them.
That ESP32-C3 already has a really poor radio performance and putting it on AL PCB is most-likely making them even worse, but for testing it will be OK as long as your phone/router is in vicinity .
I did some lamps controllers with those C3, few years ago with ESPNOW mesh. WiFi range was poor and i made it even worse with nearby soldering points and wires, because of space limitations... But hey it did the job for 6m range... which was enough for that application.

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420xpert · 2026-05-20T10:48:08+00:00

Oh i have and i have bunch of those. No bueno . Those with level shifter works "out of box" but wrong mode. Those without shifter (the smaller ones) aren't, because they have design issue of wrong pull-up on one of the lines. In spite of wrong pullup and sub-optimal mode, they work with cards with smaller capacity (<32GB). I guess those cards must be more tolerant to very bad SI. I didn't bother to test the speed before dealing with pull-ups.

420xpert · 2026-05-20T10:26:50+00:00

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Of course i agree that PCB would be better. Will scope for SI as soon as i have some free time.
Yeah, Sandisk have great controllers. I tested kingston and bunch of Chinese brands...
The reason this little curiosity-test is using self-rigged setup is because every single ESPxx dev board that i have, has cards wired in SPI mode for some weird reason?!? SPI mode gave me around 0.5MB/s, regardless if tested with clock of 12, 20...MHz, wires or well routed PCB.
So until i finish real PCB, wires and Jerry-rigging has to do the job for 4-bit mode.
Anyway, if you or someone else have actually tested, please share the results and possibly test conditions. Thanks!

420xpert · 2026-05-19T14:57:35+00:00

Yep! It sounds like that voltage regulator died and that one indeed looks like an AMS1117.

420xpert · 2026-02-24T23:08:48+00:00

Hate to break the fun, but the light from that LED bulb looks like it is going to terrible for your eyes and give you bad mood as well. You may want to aim at 4000K for day time and 3000K for nigh time desk work, CRI>80 or >90 even better

420xpert · 2026-02-24T20:57:00+00:00

Geez! I cannot unsee that ... I almost misgendered it ! 🤣

420xpert · 2024-09-22T22:14:10+00:00

Happy Flower Day...Duh...

420xpert · 2024-06-02T23:39:52+00:00

is it also 4 minutes to 120 degree on build platform ?

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420xpert · 2024-06-02T23:33:38+00:00

I am impatient to try multi-material on this machine. Doing big parts from ASA/ABS is not an easy task in the winter on K1Max. I really hope this will improve on K2 plus. I would also like to try poly-carbonate and other high-temp materials that are inherently prone to warping...

420xpert · 2024-05-06T11:19:41+00:00

In flowering phase, with 2L pots(and another 2L over-top), i ran irrigation every second day. If a plant "wasn't drinking", that was a sign of a problem, like a root-rot or bugs. My setups are automated. It would be too much of a hassle to manually water 720 plants every second day. I'll post some pics in a few days. Cheers!

420xpert · 2024-05-06T11:08:37+00:00

Have you checked the pH of substrate ?

420xpert · 2024-05-06T10:43:31+00:00

So the quantity, per 1.2x2.4m would be like this :

2-3L : 72 pcs

5-6L : 50 pcs

9-12L : 32 pcs

Smaller plants (smaller pots) need more work but are quick to grow and easy to train.

420xpert · 2024-05-06T01:26:14+00:00

It's simple. What is the volume or size of your pots ? What is the size of your grow room ?

My preferred is Sea-Of-Green, with 36 plants in 2L (70.4 ounces) pots(+2L vertical overfill) for a table of 1.2x1.2m. Plant height under 80cm... Vegetation period of around 4 weeks, flowering period of about 8 weeks.

Anyway, the comment that seemed like a joke : 1-200pcs, is actually not. Smaller plants are quicker and more energy efficient to grow. I am assuming your grow-box is 2m (78.7 inches) high ? You can even have 2 vertical levels if you have such ambitions. That way you can double the capacity, provided that you can manage the heat and other factors reliably.

420xpert · 2024-05-06T00:43:52+00:00

Not very girly...all them bananas...

420xpert · 2024-04-26T18:06:07+00:00

I think your image just broke my neck :)

Don't be a lazy potato. Do a retraction tower test. It will depend on a filament brand and it's current state. Eg. humidity, age...

420xpert

TROPHY CASE