Hi
We have three customized IMX8MN boards. Now, we are trying to do the ddr training & stress test.
However, two of our boards are not recognized by the PC at all. Another one just got a warning of USB device not recognized. We already changed the boot mode to serial download mode.
Of cause we got the error inside ddr training and stress test tools:
ERROR: Can't open USB device!!!
Please check if the correct target is selected and set to the serial download mode
We are using the PMIC of PCA9450 with a 2Gb DDR4. Here is the power rail supply from the pmic I measured(when in serial download mode before firmware download):
| VSYS_5V | 5V |
| PCA9450B_BUCK1(VDD_SOC&VDD_DRAM) | 0.85V |
| PCA9450B_BUCK2(VDD_ARM) | 0.85V |
| PCA9450B_BUCK4(VDD_3V3/NVCC_3V3) | 3.3V |
| PCA9450B_BUCK5(VDD_1v8/NVCC_1V8) | 1.8V |
| PCA9450B_BUCK6(NVCC_DRAM) | 1.1V |
| PCA9450B_LDO1(NVCC_SNVS_1V8) | 1.78V |
| PCA9450B_LDO2(VDD_SNVS_0V8 ) | 0.8V |
| PCA9450B_LDO3(1V8_VDDA) | 1.8V |
Base on my understanding, the firmware download in ddr test tools(download into on-chip internal RAM) only needs the basic voltage(default config).
Where should I have a check in the next step?
Thanks.
