Flash/SD booting TE0706+TE0720 problems

[trondeaa]

I am struggling to make boot mechanism to work.

We are using a combination of TE0706-04-A and TE0720-04-61Q33MA.
For design entry we are using VITIS/VIVADO 2025.1

Entering a simple design with bare metal works fine and the Hello world example is working without problems.
We have made a very small application toggling one I/O-pin
When we build the bootfile we are able to program the flash if the board is in SD boot mode.

BUT:
It refuses to boot when set to FLASH boot mode (after flash has been programmed).
It also refuses to boot with a SD card programmed with boot.bin and set to SD boot mode.
The FPGA is not programmed in any of these two cases.

By accident we discovered that the system was able to boot if an identical boot.bin was programmed to flash, and the same file stored on the SD card, while the board was set to flash boot (S1-3 to off).

In this case the system did boot, the FPGA was programmed and the application started.
(We tried to change details in the application, ran the program and reprogrammed the FLASH)
After reboot the application changed back to the unmodified one.
This indicates that the boot sequence fetches the application from SD.

We have not tried to find out where the bitfile for the FPGA is fetched (FLASH or SD).

[mch]

Hi,
have you set the FPGA for your desired boot mode correctly? The boot mode depends on the MODE and PGOOD signal. In the TE0706 carrier board you can change the both signals via the S1 dip switch.

Boot Mode |  S1-1 --> PGOOD | S1-3 --> MODE
QSPI      |         OFF     |   OFF
SD card   |         OFF     |   ON
JTAG      |         ON      |   ON

S1-4 --> Must be set to OFF --> EN1 = '1'
S1-2 --> Don't care, If OFF the CPLD of the module can be accessed.

Best regards,
Mohsen Chamanbaz

[trondeaa]

Hi mch :-)

This advice solved my problem. Thank you very much.
I have been very frustrated trying to figure out what I did wrong.

Originally I was looking at the schematic for version -03 where pin 1 is unconncted.

I left it untested in on position.

Looking at the schematics for version 4, I noticed that pin1 was now connected to PGOOD.


As soon as I moved the switches to off, on, off, off, booting from flash was working.
I have not yet tested booting from SD, but I assume that it will also work fine.

Once again, thank you very much for solving this frustrating situation.

Kind Regards Trond aarsaether