I am trying to set up a DMX-512 receiver using the LPC2148 Blueboard. I am
using the application note AN10717 (http://www.nxp.com/documents/applicatio ...
N10717.pdf or see the attachment) from NXP as reference. In this AN, the
receiver is based on LPC2103. I ported the code to the LPC2148 (hardly needed
any changes as all the SFR names are the same, I just changed the channel
number which is to be outputed). Also I made the schematics as shown in the AN.
But when I connect a DMX-512 transmitter (4 channel lighting control deck) to
the receiver, it doesnt function as expected. Later I modified the code in the
main loop so that the channel values received are sent to the PC through the
other UART and I observed them on TeraTerm terminal. I saw that the channel I
am trying to output shows random spurious values. It ranges from 128(min) and
188(max). It should be ideally 0(min) to 255(max) according to the protocol.
I dont understand what could be the problem? Is it a hardware problem (on the
RS485 chip side)? Or is it a software fault?
Please help me this is URGENT. I need to get it started in 1 week. Thanks in
Advance.
Regards,
Mayuresh
Original issue reported on code.google.com by daml...@gmail.com on 16 Dec 2010 at 12:22
Original issue reported on code.google.com by
daml...@gmail.comon 16 Dec 2010 at 12:22Attachments: