Lpc2000

--- In lpc2000@yahoogroups.com, Peter Homann <groups@h...> wrote:
>
> Hi,
> 
> I am migrating a serial communications interface (Modbus) to a 
LPC2138 
> processor. The Modbus spec defines that an end of message has 
occurred 
> when a period equal to 3.5 characters has passed since the last 
> character has been received.
> 
> The LPC uart can generate an interrupt if the receive buffer has 
> characters in it and no character has been received for a period of 
3.5 
> - 4.5 characters.
> 
> I would like to use this feature for detecting the end of a received 
> message. The problem I have is that if I service an interrupt due 
the 
> the buffer being filled, and it also happens that that last 
character in 
> the buffer was the last character for the received message, the 
receive 
> time-out interrupt will not occur, resulting in the end of message 
not 
> being detected.
> 
> Is there a solution, other than using a buffer length of 1 and using 
a 
> timer to measure the inter message gap?
> 
> Cheers,
> 
> Peter.
> 
> -- 
> ------------------------------------------------------------------
> Web:   www.homanndesigns.com
> email: homann@h...
> Phone: +61 421 601 665
> www.homanndesigns.com/ModIO.html         - Modbus Interface Unit
> www.homanndesigns.com/DigiSpeedDeal.html - DC Spindle control
> www.homanndesigns.com/TurboTaig.html     - Taig Mill Upgrade board
>
If you are interested in MODBUS slave for LPC213X email me 
and I can send you some code fot it 
Radim design@micronix.ca