Ashwini Shetty

Extra Byte received from SCI in HCS08

Discussion created by Ashwini Shetty on Jun 25, 2007
Latest reply on Jun 27, 2007 by David Payne
Hi all ,
 
I am working with MC13213 controller. i have written a code for SCI communication .
      ucStatus = SCI1S1;
      SCI1D = DataBuffer; ( data buffer which is to be transmitted)
      SCI1C2 = (RX_INT_ENABLE | RX_ENABLE | TX_SHIFT_REG_INT_ENABLE | TX_ENABLE); //TE bit enabled
 
now my isr gets activated.
 
    SCI1C2 &= ~(TX_SHIFT_REG_INT_ENABLE);
   
     SCI1C2 &= ~(TX_ENABLE);// TE bit disabled
 
This works really fine and i can transmit data easily without any error.
 
The problem is coming when on the same board we have interfaced MC13213 to MCHCS12DP512 (16bit controller) . The TXD1 of MC13213 gets connected to RXD1 of the MCHCS12DP512 . The moment the TE bit is disabled a character "0" gets transmitted. Is this the idle character which gets queued up?? But why doesnt it appear when i use only MC13213 with a serial port connected to hyperterminal. why is this happening only i interface those two controllers?

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