Part Number: TDA4VL-Q1
Hello Ti Colleauges,
We need information to understand if device is in SDR or DDR mode?
Following parameters are set for OSPI communication on application side:
- DDR mode enabled on OSPI device side (0xE7 value written into VCR register of the OSPI device[DDR octal with DQS])
- DDR read opcodes used: (0x9D / 0xFD)
- DQS signal generated by OSPI device as per datasheet documentation for above mentioned read opcodes
- On TI uC side
- DTR protocol enabled (DDR based signal capturing)
- PHY module disabled (DQS signal not considered, internal clock used for capturing)
- Driver strength on uC side configured as per SID document
- On device side Driver Strength is default (50 Ohm).
With above configuration we expect the device to work in DDR mode.
But we observe few more things, for which we need clarifications
DDR_EN_FLD is always set to 0.
And we see in TRM 
If DDR_EN is set to 0, then it is mentioned that data,address is SDR. Does this mean we are in SDR mode or still in DDR mode. I have attached ospi_reg dump for more info(ospi_reg.txt)ospi_reg.txt . Also can you please confirm with above settings the if DQS is not considered by uC even if it is generated by device?
Also after some analyisis, DDR_EN_FLD, which is set during initialization of the driver (performed directly after setting 0xE7 value into VCR register of the device) and then is cleared after setting read opcode(0x9D). (Nor_ospiSetOpcode() in this function)
The DDR_EN_FLD is cleared but never set back again in case DTR is enabled, so even if tuning is enabled on application side, the DDR_EN_FLD is always zero.
Can you please help us understand what exact meaning DDR_EN_FLD has ?
Also we got feedback from our hardware team that we need to set DDR_READ_DELAY_FLD 7, currently it is 0. Is there a possibility to do this?
