Yahoo Groups archive

Lpc2000

Index last updated: 2026-04-28 23:31 UTC

Thread

lpc 210x Uart1 modem interface

lpc 210x Uart1 modem interface

2005-04-28 by rohan patil

hi
i m final year elect. engg student
in my project i m interfcing lg cdma phone with 
lpc 2106 . this cdma phone has data cable which
contains rs 232 converter in it.
normal rs 232 drivers such as max 3232 gives inverted
outputs & modem interface pins of uart 1 are active
low so total system works perfectly
but i want to remove that rs 232 converter & i havent
provided inverter in hardware . what is the software
solution so that system will work perfectly?

________________________________________________________________________
Yahoo! India Matrimony: Find your life partner online
Go to: http://yahoo.shaadi.com/india-matrimony

Re: [lpc2000] lpc 210x Uart1 modem interface

2005-04-28 by sudip nag

If are you trying to connect directly from LPC UART pins to mobile phone's UART eliminating RS232 transceivers in both end, there need not be any software change. You have to open the phone cover and solder onto PCB. No hardware inverter is required. But do not connect LPC pins directly into phone RS232 jack.
 
Sudip Nag

rohan patil <iamrohanpatil@...> wrote:
   hi
i m final year elect. engg student
in my project i m interfcing lg cdma phone with 
lpc 2106 . this cdma phone has data cable which
contains rs 232 converter in it.
normal rs 232 drivers such as max 3232 gives inverted
outputs & modem interface pins of uart 1 are active
low so total system works perfectly
but i want to remove that rs 232 converter & i havent
provided inverter in hardware . what is the software
solution so that system will work perfectly?

________________________________________________________________________
Yahoo! India Matrimony: Find your life partner online
Go to: http://yahoo.shaadi.com/india-matrimony


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

   To visit your group on the web, go to:
http://groups.yahoo.com/group/lpc2000/
  
   To unsubscribe from this group, send an email to:
lpc2000-unsubscribe@yahoogroups.com
  
   Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service. 


Yahoo! India Matrimony: Find your life partneronline.

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

Re:lpc 210x Uart1 modem interface

2005-04-28 by Owen Mooney

If you can get behind the RS232 driver in phone then you will
be able to make a direct connection from the 2106 ports to the 
corresponding micro ports of the phone (both should be 0 to 3.3 volts)

If you can't, then you cannot directly connect the 2106 ports to the 
data lines from the cdma phone. The line will not only be inverted, but
also have voltages outside the acceptable range of the 2106 ports - typically +/- 6 V.

An easy solution is a transistor invertor on each of the 2106 lines.
Use a fet and resistor for the tx line, and a npn transistor and resistor for the rx line

You can also get a tiny dallas chip that will do all of this

Owen Mooney
 

Subject: 

   hi
i m final year elect. engg student
in my project i m interfcing lg cdma phone with 
lpc 2106 . this cdma phone has data cable which
contains rs 232 converter in it.
normal rs 232 drivers such as max 3232 gives inverted
outputs & modem interface pins of uart 1 are active
low so total system works perfectly
but i want to remove that rs 232 converter & i havent
provided inverter in hardware . what is the software
solution so that system will work perfectly?

Re: [lpc2000] lpc 210x Uart1 modem interface

2005-04-29 by Robert Adsett

At 08:14 AM 4/28/05 +0100, rohan patil wrote:
>    hi
>i m final year elect. engg student
>in my project i m interfcing lg cdma phone with
>lpc 2106 . this cdma phone has data cable which
>contains rs 232 converter in it.
>normal rs 232 drivers such as max 3232 gives inverted
>outputs & modem interface pins of uart 1 are active
>low so total system works perfectly
>but i want to remove that rs 232 converter & i havent
>provided inverter in hardware . what is the software
>solution so that system will work perfectly?

Out of curiosity, why have you ruled out using a RS-232 level 
convertor?  It strikes me as a cleaner and easier solution unless you are 
building 1000's.

Robert

" 'Freedom' has no meaning of itself.  There are always restrictions,   be 
they legal, genetic, or physical.  If you don't believe me, try to chew a 
radio signal. "  -- Kelvin Throop, III
http://www.aeolusdevelopment.com/

Move to quarantaine

This moves the raw source file on disk only. The archive index is not changed automatically, so you still need to run a manual refresh afterward.