topic Re: About the ECSPI Master Mode Timing Parameters. in i.MX Processors

About the ECSPI Master Mode Timing Parameters.

takashitakahash — Fri, 25 Sep 2015 08:45:10 GMT

Hi community.

Our customer has two question below.

About the ECSPI Master Mode Timing Parameters.

1, "ECSPIx_SCLK High or Low Time (tSW)"

Read at the time of 21.5ns (min) it is would be fixed ? regardless of the setting frequency of ECSPIx_SCLK?

(If the slower the frequency of SCLK when tSW (min) will also be larger? )

2 "ECSPIx_MISO Setup Time (tSmiso)"

Read at: tSW=21.5ns(min), tSmiso 18 ns (min) seems like a tough value and nalow is it correct?

igorpadykov — Mon, 28 Sep 2015 01:35:18 GMT

Hi Takashi

1. Read time of 21.5ns (min) is not fixed, it is given for max.

available frequency and will be increased proportionally ECSPIx_SCLK frequency

2. you are right, it seems as tough at max. frequency, however ar lower

frequency this may be acceptable

Best regards

igor

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takashitakahash — Wed, 30 Sep 2015 07:46:13 GMT

Hi commujnity.

I want to make sure about the answer.

About for 1.

tSW (min) is change by setting frequency, numerical value can be calculated from the set frequency?

(50% of the set frequency cycle?)

Example) tSW value, when it is set to ECSPIx_SCLK = 20MHz (min)

And about for 2.

Please allowed to check just in case.

tSmiso is fixed min = 18ns, regardless of the setting frequency.

igorpadykov — Wed, 30 Sep 2015 08:02:23 GMT

Hi Takashi

tSW=21.5ns (min) is defined by max. operational frequency.

With 20MHz it will be T/2 (T=1/20MHz) (typ.)

yes, min = 18ns, regardless of the setting frequency

~igor