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f1fco

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Joined: 18/03/2012
Location: France
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Posted: 05:54am 13 May 2016

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is it possible to receive 7 bits serial datas on a Maximite ?
firmware 4.5

Pierre.

73s de F1FCO

Geoffg

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Joined: 06/06/2011
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Posted: 05:59am 13 May 2016

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No. It is 8 bit data with one or two stop bits.

Geoff Graham - http://geoffg.net

f1fco

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Posted: 06:03am 13 May 2016

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thank you for fast answer Geoff
and 7 bits, is it possible on a MicroMite ?
I need to read datas on 7 bits from a power counter and 8 bits is a garbage...

perhaps with a C function ?
or a future, or special, version of the firmware

PierreEdited by f1fco 2016-05-14

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MicroBlocks

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Posted: 06:14am 13 May 2016

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If it is 7 bits with two stopbits then you could configure for 8 bits with one stopbit and then disregard the one bit extra by masking it of.

Microblocks. Build with logic.

f1fco

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Posted: 06:41am 13 May 2016

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I find the Serialrx function here :
http://www.thebackshed.com/forum/forum_posts.asp?TID=7963&KW=serialrx

is it possible for the Gurus of Cfunction to have a version with the choose of numbers of bits ?
7 for me !

thank you very much

Pierre.

73s de F1FCO

JohnS
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Posted: 07:14am 13 May 2016

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How many stop bits are with the 7 data bits?

You might say what is creating them to help people...

JohnEdited by JohnS 2016-05-14

f1fco

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Posted: 07:24am 13 May 2016

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1200 or 9600 bauds
7 bits datas
even parity
1 stop

Pierre.

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MicroBlocks

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Posted: 07:36am 13 May 2016

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8 bit 1 stop bit will work
The total number of bits that are send are still 9
7 bits + parity + stop = 9 bits.
8 bits + stop = 9 bits.

Just disregard the parity bit.
Best is to examine the values by looking at their binary representation.
Without the last bit the received data should make sense.

Microblocks. Build with logic.

JohnS
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Posted: 07:51am 13 May 2016

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^^^
what he said!

John

Justplayin

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Joined: 31/01/2014
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Posted: 08:33am 13 May 2016

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Seems like 8N1 should work, then AND the received data with "01111111" to remove the parity bit.

--Curtis

I am not a Mad Scientist... It makes me happy inventing new ways to take over the world!!

MicroBlocks

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Posted: 08:55am 13 May 2016

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@Geoff, would that not be a good addition to MMBasic to support 7 bits?
As described above it can be done in software if the peripheral does not support it.
There are lots of sensor and equipment that work with 7 bits and toggling/masking some bits in C is trivial.
Edited by MicroBlocks 2016-05-14

Microblocks. Build with logic.

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