Is it safe to connect two different LPC4370 MCU Unit of GPIO pins directly to each other? such that LPC4370 MCU1 transmitter of GPIO0[0] connected directly to the LPC4370 MCU2 receiver of GPIO0[0]

[sujayp]

Is it safe to connect two different LPC4370 MCU Unit of GPIO pins directly to each other? such that LPC4370 MCU1 transmitter of GPIO0[0] connected directly to the LPC4370 MCU2 receiver of GPIO0[0]

I am working on an LPC4370 project that requires me to route the output of one GPIO pin in transmitter MCU1 into the input of another GPIO pin in Receiver MCU2 .so I have thinking of connecting directly to each other.

I will be configure a one pin as output and another as input. Is it it would  create any trouble.

Thinking about it in retrospect, putting a current-limiting resistor between the two pins would have prevented any worries, or it would require any hardware design to do at this point.

Can we connect directly?

Is it possibility of a programming error causing both to be (possibly conflicting) outputs

[a_bet]

Hi Sujay,
I'm working on the LPC4370 too in these days, but I'm far to be an expert, so take everything I say as a piece of advice and not a go to solution.
However, since this is intended to be a transmission line I'd expect an adapted termination to avoid reflections, and while designing it I'd be careful about the tolerance of the LPC4370 in terms of input/output currents.
Here's a simple schematic of (what I think might be) a possible solution.
A well known book for reference is the following: High Speed Digital Design: A Handbook of Black Magic: Martin Graham: 9780133957242: Amazon.com: Book... 

Good luck with your project.

[sujayp]

Hi ,

Thanks for the Reply, actually it is possible to add any High-Speed Differential Line Drivers and Receivers ICS between the 2 GPIO pins such that propagation delay is in few 5.0 nano seconds and the current limiting any where between +/- 30 mA

Is it possible for you to forward the E-book High Speed Digital Design: A Handbook of Black Magic: Martin Graham to my personal email address sujay@ifuturemec.com.

The book would cost around $ 100.00 which is a expensive to buy the book at this stage.

And one more thing , the Operating frequency of the LPC4370FET256is 204 MHz, If I am not wrong in order to execute each instruction is it , it would take around 5.0 nano seconds time.

I am now completed the schematics design and want move the schematics to the PCB design.

Please if you have time , you can  reply

Regards

Sujay

[a_bet]

I'm sorry Sujay, but the image I posted is from some slides that were part of a university course here in Italy: I don't own any copy of the book so I can't send it to you.  I know it's quite expensive and that's why I didn't get one neither.

And one more thing , the Operating frequency of the LPC4370FET256is 204 MHz, If I am not wrong in order to execute each instruction is it , it would take around 5.0 nano seconds time.

Yes i can confirm that this is the expected execution time of each instruction: if you need an in-dept view of the M4 core I suggest another book (that I actually bought few weeks ago): The Definitive Guide to ARM® Cortex®-M3 and Cortex®-M4 Processors, Third Edition: Joseph Yiu: 978012...   , but since you're planning to make a PCB I imagine you'll already know this one.

Regards,
Andrea

[sujayp]

Hi

I once again thanks for the reply, actually I had a soft copy of the The Definitive Guide to ARM Cortex-M3 and Cortex-M4 Processors, Third Edition: Joseph Yiu and I am going through this book and Next i have to choose  which version of the Software and JTAG programmer usually used for debug and loading the program for the LPC4370FET256FBGA,

Will you please help in this regards?

Regards

sujay

[a_bet]

Hi again Sujay.
Well done, it's a good book, hope you'll enjoy it.
Actually I'm using LPC link2, which is a good evaluation board to if you'll want to try out, but depending on the IDE there might be better options which unfortunately I still haven't use.
Check the LPC Link2 product page on NXP.com and also @embedded artists' website!
Regards,
Andrea