STM32MP157FAD1

[filip1785]

Hello,

I would like to ask you few questions since I have some unclearances about STM32MP157F MPU:

1. If 933MHz DDR3L RAM was connected to the MPU according to the schematic, will the MPU automatically underclock it to max 533MHz?

2. Is it possible to connect an OLED display to the STM32MP157F?

3. Since SLC NAND memories are quite expensive in higher densities (>= 16GB), would it be a problem if a different configuration  such as TLC was used? Does the cell configuration also matter in e.MMC and what is its max data transfer rate for read/write when connected to SDMMC, if the datasheet says max I/O speed is 208 MB/s? Would it be possible to use HS200 mode to take advantage of the maximum capabilities of the MPU?

4. If the Wi-Fi + Bluetooth module has a Wi-Fi SDIO host interface and as stated , the SDMMC supports data rates up to 208 MB/s, would it be possible to use the Wi-Fi 5/6 module to also take advantage of the MPU maximum capabilities instead of the Wi-Fi 4 65Mb/s (8,125MB/s) 1DX module used in the Discovery Kit?

I am aware that my questions may be a bit trivial to stupid as I am not an expert in this field, but thank you very much in advance for any response.

Sincerely

[PatrickF · Accepted solution]

HI @filip1785 

1. there is no 'autodetection' of DDR speed (like you could have on PC SODIMM). The DDR configuration should be done according to DDR datasheet. Obviously a faster DDR would work at 533MHz max. Please see AN5168.
2. Display technology does not matter, what is important is the interface. We could support RGB parallel or DSI display. Please have a look to product documentation (RM0436 and DS12505) or board examples for details.
3. SLC is required for parallel NAND connected on FMC, we did not support other memory than the one requiring BCH4 or BCH8 ECC strength.
   For eMMC, we support all flavors as NAND cell management is hidden by controller inside eMMC. eMMC speed is limited to somewhat 50 MBytes/s (please see ES0438)
4. as SDMMC is limited to 50MBytes/s (raw bandwidth), and there is usually some protocol and CPU load overhead, there is no 'bare' speed gain using WIFI5 or 6. As those standard are using other frequency bands and different coding there could be some beneficial to use it in some cases (i.e. 2.4GHz band saturation).

You are welcome to ask even trivial questions.
If you are not confident or expert in some area, we recommend to stick as much as possible to existing solutions provided by ST (STM32MP157F-DK2 or STM32MP157F-EV1) or 3rd party like SOM modules (please have a look to partner page). This will reduce your overall effort and risks.

Regards.