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Josef Albersmann
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UART Boot - timings

The AN-B-001 Booting from Serial Interfaces explains the UART Boot protocol.
A) Are there any timing for answering on STX (or a time window within the answer has to be done) ?
115.200kbps / 57.600kbps

Background:
Using smart snipped on UART 1 (Standard PC UART Port without USB) does not work on a very fast PC at 115.200 kbps.
It works fine with 57.600kbps
V24 Level Converter (Maxim) seems to be OK (Signals verified by Scope)

MHv_Dialog
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Hi Josef,

Hi Josef,

So you have it working at 57k6 using P0_0 and P0_1 (or P0_4 and P0_5), but not at 115k2 using P0_2 and P0_3? 

One reason could be that the 115k2 of the DA14580 running at 16MHz, is about 3.5% off on the baud rate. If your PC and converter is off by 1.5%, this could be a problem.

The timing of responding to the STX from the DA14580 isn't all that critical, so I will assume for now that this isn't your problem. I have asked internally what the timing requirement is.  

 

Josef Albersmann
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Thank's for the information.

Thank's for the information.
I will try to measure the UART Bit length to double check if this might be the problem.

Josef Albersmann
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Any Updates on related time

Any Updates on related time constrain for UART Booter communication?

Josef Albersmann
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OK... / new document AN-B-001

OK... / new document AN-B-001 V1.4 clarifies my question.

Ticket could be set to 'done'

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