ESP32 Forum

hi guys

brand new -

ESP32-PRO new IoT board with 4MB external RAM, 4MB external Flash, external crypto engine, LiPo charger

look at olimex blogs for more details.

this is Open Hardware and Software and you find the shematic on github

this ESP32-Pro is a combine with PIC32, comes with USB-OTG, USB-Device and more.

also there is crypto chip from MC ATECC508A for P2P, M2M and other secure IoT projects.

best wishes
rudi

We had to go to bare ESP32 chip as the RAM signals are not available on WROOM neither WROVER modules

Makes no sense. WROOM has all the pins. WROVER doesn't have 16,17 but RAM is on module so why would you need it?

To be fair, WROOM uses 3.3V flash and as such isn't directly compatible with 1.8V PSRAM chips. You're right wrt the WROVER module, though.

ESP_Sprite wrote:To be fair, WROOM uses 3.3V flash and as such isn't directly compatible with 1.8V PSRAM chips. You're right wrt the WROVER module, though.

True but there are purportedly 3.3v psram chips out there. I don't really see a reason to not use wrover module on this board (besides the fact they still aren't shipping yet).

WiFive wrote:\I don't really see a reason to not use wrover module on this board (besides the fact they still aren't shipping yet).

They may be able to achieve tighter layout without the module. Not sure what their assembly costs are (so no clue if it's a win or loss in that respect). OTOH they possibly need to go through FCC/CE.

ESP_igrr wrote: They may be able to achieve tighter layout without the module. Not sure what their assembly costs are (so no clue if it's a win or loss in that respect). OTOH they possibly need to go through FCC/CE.

That is possible, but I think most of their boards are two layer and will have routing, RF and impedance control considerations. WROVER can hang the antenna off the board and has cleaner routing. I think they do PCBA in house but would be surprised if savings got to $1/pc. Anyway, whatever works. Variety is OK.

ESP_Sprite wrote:To be fair, WROOM uses 3.3V flash and as such isn't directly compatible with 1.8V PSRAM chips. You're right wrt the WROVER module, though.

to be correct, and to be better informed
not only not compatible to 1.8V psram
it was never tried (HRD) to combine 3.3 flash with 3.3 psram
cause
- there would be too much switching noise
- V^2 -> 4 times the energy
- and more power

WiFive wrote:

We had to go to bare ESP32 chip as the RAM signals are not available on WROOM neither WROVER modules

Makes no sense. WROOM has all the pins. WROVER doesn't have 16,17 but RAM is on module so why would you need it?

makes sense, see my answere.

WiFive wrote:

ESP_Sprite wrote:To be fair, WROOM uses 3.3V flash and as such isn't directly compatible with 1.8V PSRAM chips. You're right wrt the WROVER module, though.

True but there are purportedly 3.3v psram chips out there. I don't really see a reason to not use wrover module on this board (besides the fact they still aren't shipping yet).

you are 90 prozent right, wroom32 have all ( without vdd_sdio ) break out to pinheader
it makes no sense, to change the 3.3v flash to 1.8v flash that is possible to combine with 1.8 psram,

Double cost flash
- you pay the share of flash in wroom32
- you need a new flash 1.8
- you have to change it 3.3 -> 1.8
In short, open, remove, assemble, close.
- double cost
- extra work
then all extra work done you have a new sense:
- no vdd_sdio 1.8v break out for pull up psram /cs

this makes really no sense to use then wroom32 with psram



but i think this psram theme has been discussed deeply and emotionally enough here.

OK if you want vdd_sdio for sleep and you exclude 3.3v psram then wroom is out.

If you want custom flash sizes (and low volumes/short lead times) then wrover is out.

hi guys

next week is X-Mas -- and we celebrate few days earlier -

got it
on weekend more details - just in time unpacking and few testings.
( teardrops full of joy )

best wishes
rudi

@Rudi
Loooks very nice. I'm planning to use the PSRAM as graphical buffer, so if you ever make it throught the testing, and start making it I'm a buyer!!!!

Note: I'm very surprised you are using a PIC32. The Arm Cortex M0 micros are better IMO.

I would have rather gone with an Atmel ATSAMD21G micro, which is an Arm Cortex M0+ micro, and has all the features of the PIC.
It is also much cheaper than the PIC.
If you check on Mouser for example.
- Price of PIC32MX270F256DT - 3,18 EUR/pc (in Qty of 1600 reel)
- Price of ATSAMD21G18A (48pin TQFP version) - 2,74 EUR/pc (single buy), 2,22-EUR/pc in case of a reel of 1000.

1 EUR cheaper even in masses!

Plus this is the micro used in the Arduiono M0, and has a valid Arduino bootloader (to be loaded with a Cortex programmer) and can be programmed with Arduino IDE afterwards.

AtsamD21 features in a nutshell:
TQFP-48 package (or bigger, but the TQFP-48 is a usable size)
Arm Cortex M0 core, 32bit, DMA, all that thing, you name it
48MHz to 96 MHz clock speed
JTAG and 2 wire SWD programming, or through UART or USB (depending on bootloader)
USB either device or host mode supported. It can be essentially a full USB host.
Capacitive Touch (thorugh PTC periferial)
Lots of SPI, lots of I2C, and I2S

This Micro was my first candidate to be used in my IoT project... untill I found the holy grail (ESP32).

Vader