Dear Sir or Madam,
Boot: Parallel NOR Flash (EIM_CS0)
Refer to Table 43. EIM Asynchronous Timing Parameters Table Relative Chip to Select in IMX6SDLAEC(Rev.3.0).
There is below description.
"WE35" : Max "3 + (OEA - RCSA)"
My customer set the OEA = 0 and RCSA = 0.
So, It should become WE35 = Max 3 [ns].
But, my customer observed WE35 = 20 [ns] with 1st access on custom board.
I reproduced this issue following steps on SABRE-AI.
1. Start-up the SABRE-AI from Parallel NOR.
2. Measured 1st clocks of CS and OE.
3. You can see the 20 [ns] delay.
Why was WE35 = 20 [ns] observed with 1st clock?
Refer to OEA bit of EIM_CSnRCR1 field descriptions in i.MX6SDLRM(Rev.1) (P.1043).
There is description of "If EIM_BOOT is 1, the reset value for EIM_CS0RCR1 is 0b010".
Could you tell me the external pin connected with "EIM_BOOT"?