ESP_Sprite wrote:No, sorry. The flash and psram have slightly different timing requirements, and the intrinsics of the cache mechanism makes it impossible to cater to both using one clock line. I was surprised by that myself as well and suggested a few workarounds to the digital team, but seems they already thought of all of them and the only way to make it work is by using a separate clock line.
separate clock line
then sry - this info
in the tech referenz manual is then wrong and a bug - please add me to the bug bounty for it
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- 0_pSRAM-ESP-tech_ref.jpg (63.07 KiB) Viewed 14939 times
ivan
tweets last hours the same and i think then the referenze manual need an update asap and very fast.
now the pSRAM puzzle becomes more face
D0WD:
we need 1.8V, S3:S0 share pins, CLK and CS is difference to the Flash, pSRAM use IO16 for CS and IO17 for CLK
D2WD:
we need 1.8V
In D2WD, the flash chip is connected internally to GPIOs 6 (clk), 7(wp), 8(d), 11(hd), 16(cs), 17(q).
This is pre-configured using SPICONFIG_ block of fields in the EFUSE.
and now we know the CS( IO16) and CLK (IO17) pin in Wrover.
so we can now use and test the wrover we bought from espressif in the past with PSRAM support.
the information is hidden on the street - you just have to find it and put it together.
this info in the technical referenze manual Is very dangerous -
i am glad the routing here in the PCB has not yet finished and charged tasks;
it is the same theme as for SD and SD host. many
have wrongly shared the pins - and gived up the next Revision ( olimex REV B comes not out! )
but now we hear from ivan and jeroen the facts. so i will bookmark this for psram here for the future askings and reference and for it.
one
new info we get today to:
Okay, can i finally give the reason why we don't burn the efuse for 1.8V in D2WD. The reason is, if the VDD_SDIO is configured by efuse, it takes some time for the hardware to read efuse values at startup. If the strapping pin configures VDD_SDIO to be 3.3V, then during this time, VDD_SDIO will be 3.3V. As soon as efuse read is complete, the regulator will switch to 1.8V.
We never learn everything here - and out.
Every day we learn more