How to configure external memory in NUCLEO-H745ZI

ggowd.1 · ‎2024-03-22

Hello Team,

I want to add external memory to NUCLEO-H745ZI board. In that board i have configured 2SPI, Ethernet (without RTIOS) and Timmer for that I need huge memory. This there any configuration or steps to add external memory to board.

Best Regards,
Gagan Gowda

LCE · ‎2024-03-25

Better check again which / if DMA can access which RAM areas, incl. external.

SofLit · ‎2024-03-25

Unfortunately, you cannot use SDRAM for this specific package STM32H745ZI LQFP144 as FMC_SDNCAS alternate function is not available! You need to select another package.

To give better visibility on the answered topics, please click on "Accept as Solution" on the reply which solved your issue or answered your question.

ggowd.1 · ‎2024-03-25

Hi SofLit,

Can you suggest package that can used with SDRAM?

Best Regards,
Gagan Gowda

SofLit · ‎2024-03-25

You can use LQFP176 instead.

To give better visibility on the answered topics, please click on "Accept as Solution" on the reply which solved your issue or answered your question.

ggowd.1 · ‎2024-03-25

Hi SofLit,

Can you conform if we can proceed to design our own PCB for STM32H745XIH6U with LQFP176 for external SDRAM.

Best Regards,
Gagan Gowda

SofLit · ‎2024-03-25

Hello,

STM32H745XIH is the TFBGA240+25. If you can use it go ahead. It's already used in the TM32H745I-Disco board but it's hardwired in 16-bit mode.

For LQFP176 you need to order the part number: STM32H745IITX

Where X = 3 or 6:

3: you can't exceed 300MHz at the temperature range indicated above. While 6 you can reach up to 480MHz in LDO mode in the range of -40 to 85°C

Hope I answered your questions

To give better visibility on the answered topics, please click on "Accept as Solution" on the reply which solved your issue or answered your question.

SofLit · ‎2024-03-25

Sorry If you need 32-bit mode with an LQFP package you need to select LQFP208

To give better visibility on the answered topics, please click on "Accept as Solution" on the reply which solved your issue or answered your question.

ggowd.1 · ‎2024-03-25

Hi SofLit,

Thank you so much. In STM32H745IIT6 for LQFP176(package) microcontroller is there any NUCLEO Board by STM

Best Regards,
Gagagn Gowda

SofLit · ‎2024-03-25

Unfortunately Not.

If you want to start with an existing board you can purchase STM32H747-DISCO board.

It has already a hardwired 32-bit SDRAM.

Schematics from here.

Board's user manual and related documentation from here

SDRAM driver (BSP) from here.

To give better visibility on the answered topics, please click on "Accept as Solution" on the reply which solved your issue or answered your question.

MM..1 · ‎2024-03-25

You still dont reply for what you need buff. SPI or any other bus can send data in packets or continuosly. This is irelevant, because you on receive side set how and where is data stored. Normal system :

1. For simple match 1000 buffer start DMA receive

2. Half complete interrupt 500 is in memory next 500 continues on hw offload dma

3. your code in interrupt for half complete make job with this data and must be quick before next 500 arive.

4. Full complete interrupt repeat point 3 with data 500-999 and receive next 0..499 in circular mode

Use for this external SDRAM is waste of all planet resources...