AVR-Chat

hi friends,
i want to convert baud rate of input data from a medical module.
my data is 60 packet per second & every packet includes 5 bytes.
this is also 8 data,1 stop & odd parity.  
therefore,my data is 4800bps & i must convert it to 9600bps because of my RF module.
my RF module can transmit a data that is 9600bps with odd parity,but it cant transmit 4800bps with odd parity correctly & when it transmits this data some byte cant be transmitted such as 45 or 7F(hexa).
also i wanna to know how odd parity work & what is its detail.

--- In AVR-Chat@yahoogroups.com, "iijfet" <iijfet@...> wrote:

>
> hi friends,
> i want to convert baud rate of input data from a medical module.
> my data is 60 packet per second & every packet includes 5 bytes.
> this is also 8 data,1 stop & odd parity.  
> therefore,my data is 4800bps & i must convert it to 9600bps because of my RF module.i use a atmega64 chip & write a suitable code at codevision.
> my RF module can transmit a data that is 9600bps with odd parity,but it cant transmit 4800bps with odd parity correctly & when it transmits this data some byte cant be transmitted such as 45 or 7F(hexa).
> also i wanna to know how odd parity work & what is its detail.
>

--- In AVR-Chat@yahoogroups.com, "Dave McLaughlin" <dave_mclaughlin@...> wrote:
>
> Hi there,
> 
>  
> 
> What is the input to the RF transmitter? Does the RF transmitter have
> onboard encoding to handle the air interface? IE, does to take your data and
> convert it to some form of RETURN TO ZERO format such as Manchester encoding
> or PWM?
> 
>  
> 
> Do you have a datasheet link to the RF module you are using? It would be
> useful to know what the module is expecting and help us figure out what you
> need.
> 
>  
> 
> There is a nice little intro to serial communications here that explains the
> use of the parity bit. It is a very simple way to check bytes for simple
> errors but not reliable enough to guarantee good communications. Better to
> use some form of CRC or other error correcting as part of your telegram.
> 
>  
> 
> http://www.taltech.com/TALtech_web/resources/intro-sc.html
> 
>  
> 
>  
> 
>  
> 
> From: AVR-Chat@yahoogroups.com [mailto:AVR-Chat@yahoogroups.com] On Behalf
> Of iijfet
> Sent: 18 August 2009 13:25
> To: AVR-Chat@yahoogroups.com
> Subject: [AVR-Chat] 4800bps to 9600
> 
>  
> 
>   
> 
> hi friends,
> i want to convert baud rate of input data from a medical module.
> my data is 60 packet per second & every packet includes 5 bytes.
> this is also 8 data,1 stop & odd parity. 
> therefore,my data is 4800bps & i must convert it to 9600bps because of my RF
> module.
> my RF module can transmit a data that is 9600bps with odd parity,but it cant
> transmit 4800bps with odd parity correctly & when it transmits this data
> some byte cant be transmitted such as 45 or 7F(hexa).
> also i wanna to know how odd parity work & what is its detail. 
> 
> 
> 
> [Non-text portions of this message have been removed]
>
my RF is HM-TR :
http://www.hoperf.com/pdf/HM-TR_EN.pdf
http://www.hoperf.com/tools/HM-TR_SETUP.exe
 the data which i explain it, is transmited by a medical module & i wanted to send it to  RF module,but it needs a micro to convert baud rate.

Hi there,

 

What is the input to the RF transmitter? Does the RF transmitter have
onboard encoding to handle the air interface? IE, does to take your data and
convert it to some form of RETURN TO ZERO format such as Manchester encoding
or PWM?

 

Do you have a datasheet link to the RF module you are using? It would be
useful to know what the module is expecting and help us figure out what you
need.

 

There is a nice little intro to serial communications here that explains the
use of the parity bit. It is a very simple way to check bytes for simple
errors but not reliable enough to guarantee good communications. Better to
use some form of CRC or other error correcting as part of your telegram.

 

http://www.taltech.com/TALtech_web/resources/intro-sc.html

From: AVR-Chat@yahoogroups.com [mailto:AVR-Chat@yahoogroups.com] On Behalf
Of iijfet
Sent: 18 August 2009 13:25
To: AVR-Chat@yahoogroups.com
Subject: [AVR-Chat] 4800bps to 9600

 

  

hi friends,
i want to convert baud rate of input data from a medical module.
my data is 60 packet per second & every packet includes 5 bytes.
this is also 8 data,1 stop & odd parity. 
therefore,my data is 4800bps & i must convert it to 9600bps because of my RF
module.
my RF module can transmit a data that is 9600bps with odd parity,but it cant
transmit 4800bps with odd parity correctly & when it transmits this data
some byte cant be transmitted such as 45 or 7F(hexa).
also i wanna to know how odd parity work & what is its detail. 



[Non-text portions of this message have been removed]

Just a quick note to take into account your occupancy of the channel, "Good" Devices Listen Before Talk and try not to interfere with other devices out there or interfere with your device. Try to minimise the tx time and channel occupancy. This will enahnv=ce the intergrity of your data and ithers around you.

Regards

--- In AVR-Chat@yahoogroups.com, "iijfet" <iijfet@...> wrote:

>
> hi friends,
> i want to convert baud rate of input data from a medical module.
> my data is 60 packet per second & every packet includes 5 bytes.
> this is also 8 data,1 stop & odd parity.  
> therefore,my data is 4800bps & i must convert it to 9600bps because of my RF module.
> my RF module can transmit a data that is 9600bps with odd parity,but it cant transmit 4800bps with odd parity correctly & when it transmits this data some byte cant be transmitted such as 45 or 7F(hexa).
> also i wanna to know how odd parity work & what is its detail.
>

OK. This has onboard handling of the air interface which does away with any
additional coding at your end other than some form of CRC etc.

 

A quick look at the datasheet says that it can be setup for 4800, 8, ODD, 1
which would match your medical data output so I can't see any reason it
won't work.

 

If you do have to convert to 9600 to use the unit as it comes from the
factory, you should use 9600, 8, None, 1 as your data rate. This way you
have no need to reprogramme the RF module and in theory you should be able
to get it working simply by sending your data to it.

 

Dave.

From: AVR-Chat@yahoogroups.com [mailto:AVR-Chat@yahoogroups.com] On Behalf
Of iijfet
Sent: 18 August 2009 13:54
To: AVR-Chat@yahoogroups.com
Subject: [AVR-Chat] Re: 4800bps to 9600

 

  my RF is HM-TR :
http://www.hoperf.com/pdf/HM-TR_EN.pdf
http://www.hoperf.com/tools/HM-TR_SETUP.exe
the data which i explain it, is transmited by a medical module & i wanted to
send it to RF module,but it needs a micro to convert baud rate.



[Non-text portions of this message have been removed]

On Tue, Aug 18, 2009 at 2:24 AM, iijfet<iijfet@yahoo.com> wrote:
> hi friends,
> i want to convert baud rate of input data from a medical module.
> my data is 60 packet per second & every packet includes 5 bytes.
> this is also 8 data,1 stop & odd parity.

You don't normally see 8 data bits used with parity, and most usarts
will not do that.
I suspect you either have 7 bit, odd parity, 1 stop, or 8 bit, no
parity, 1 stop.

> therefore,my data is 4800bps & i must convert it to 9600bps because of my RF module.
> my RF module can transmit a data that is 9600bps with odd parity,but it cant transmit 4800bps with odd parity correctly & when it transmits this data some byte cant be transmitted such as 45 or 7F(hexa).
> also i wanna to know how odd parity work & what is its detail.

The number of 1 bits in the byte will always be 1,3,5 or 7,
The parity bit is set or cleared to make this true.

>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
>