Differences between i.MX251 and i.MX257

[shigehisayamamo]

Hi all,

I am attempting to develop device drivers and middleware using i.MX251.

I have developed software (device drivers, middleware and application) with i.MX257.

I would like to port the existing software (using i.MX257) into i.MX251.

I have read the below MX25 datasheet and reference manual to find the differences between i.MX251 and i.MX257 as shown below.

- IMX25AEC Rev. 10, 06/2013

- IMX25CEC Rev. 10, 07/2013

- IMX25RM Rev. 2 01/2011

I got the following diff with the datasheet.

----------------------+------------+-------------

                            i.MX251  |  i.MX257

----------------------+------------+-------------

PATA/CE-ATA   |    -          |     yes

----------------------+------------+-------------

LCD Controller   |    -          |     yes

----------------------+------------+-------------

Touchscreen      |    -          |     yes

----------------------+------------+-------------

CSI                     |    -          |     yes

----------------------+------------+-------------

Security              |     yes     |    -

----------------------+------------+-------------

It seems that no functional difference between i.MX251 and i.MX257 except above.  And memory map, boot sequence and internal registers configurations of i.MX251 seems to be same as i.MX257.

So I think I can re-use the existing software (device drivers and middleware) which were developed for i.MX257 into i.MX251.  But not sure!

Then could you please advise to my questions below?

1. Is my understanding correct on the difference between i.MX251 and i.MX257? i.e. the only difference between i.MX251 and i.MX257 are the table I wrote above?
2. Excepting hardware functional difference, can I use the existing software (device drivers and middleware) which were developed for i.MX257 into i.MX251 without changing?
3. How and where can I get the comparison table between i.MX251 and i.MX257?

I would appreciate it if you could answer to my questions.

Thank you,

Shigehisa Yamamoto

FAE

eSOL Co., Ltd.

[shigehisayamamo]

Hi igor,

I'm sorry pester you, but i need one more advice you.

In table 2 of "Document Number: IMX25AEC Rev. 10, 06/2013", security feature is supported by both i.MX251 and i.MX255. But Table 2 of "Document Number: IMX25CEC Rev. 10, 07/2013", it says that i.MX257 does not support security. I just want clarify this difference.  The i.MX251 supports security, but i.MX257 does not support security.

Correct?

Best regards,

Shigehisa

[igorpadykov · Accepted solution]

Hi Shigehisa

correct, i.MX257 does not support security.

Best regards
igor

[shigehisayamamo]

Hi igor,

Thank you for your answer. Everything has been cleared. I can close this ticket.

Thank you again for your help and support!

Shigehisa

[igorpadykov]

Hi Shigehisa

differencies are provided on Table 2. i.MX25 Parts Functional Differences
https://www.nxp.com/docs/en/data-sheet/IMX25AEC.pdf

one can use existing software (device drivers and middleware) which were developed for i.MX257 and

excluding module drivers from linux image which are not present in i.MX251. As porting guide one can refer to i.MX53 UG

https://www.nxp.com/docs/en/user-guide/MX53UG.pdf 

Best regards
igor
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[shigehisayamamo]

Hi igor,

Thank you for your quick reply.

The Table 2 you mentioned is the comparison table for i.MX251 and i.MX255. What I need is the info on functional comparison for i.MX251 and i.MX257. Can you give further advices to me to understand the difference on these processors?

Regarding software porting, our device drivers and middleware are run on RTOS (eT-Kernel) and not linux. Do you have any reference document for RTOS?

Best regards,
Shigehisa

[igorpadykov]

Hi Shigehisa

>The Table 2 you mentioned is the comparison table for i.MX251 and i.MX255. What I need

>is the info on functional comparison for i.MX251 and i.MX257. Can you give further advices

>to me to understand the difference on these processors?

except differencies given in Table 2, two parts are identical.

>Do you have any reference document for RTOS?

not, sorry.

Best regards
igor