I read the data sheet of i.MX6ULL Table 42. Asynchronous Mode Timing Parameters.
It shows data setup/hold time at EDO mode.
When EDO mode, NF16=tDSR=18.28nS and NF17=tDHR=11.83nS fixed value. the condition is
While in the Reference manual, there is a description, "If the GPMICLK period is greater than 6ns (and not greater than
12ns), set the GPMI_CTRL1[HALF_PERIOD]=1; This will cause the DLL reference
period (RP) to be one-half of the GPMICLK period." in 18.104.22.168 NAND Asynchronous EDO Mode Timing.
According to this, GPMICLK is between 166MHz to 83MHz, it should be set GPMI_CTRL1[HALF_PERIOD]=1.
However, data sheet describe like above, when GPMICLK is 100MHz , it is GPMI_CTRL1[HALF_PERIOD]=0.
at EDO mode
1. Is it OK to set GPMI_CTRL1[HALF_PERIOD]=0 at 100MHz?
2. When set GPMI_CTRL1[HALF_PERIOD]=1, can we still use the data setup time and hold time constant value in data sheet NF16 and NF17?