In our design we are using AM1810BZWTA3 processor.Currently we are testing uPP in 8 bit with loopback mode Channel A to B & Channel B to A.
1/ Channel A to B:
Upp Register Configurations :
a/ uPP_UPCTL Register Value---->0x00000007 (A is Tx and B is Rx)
b/ uPP_UPICR Register Value---->0x00180020 (Signals are enabling related to A(Tx) and B(Rx))
c/ uPP_UPTCR Register Value---->0x00030303 (Transmit threshold and Read threshold for DMA Channel Q and I are set to 256 bytes)
d/ Digital Loop Back A to B is Enabled uPP_UPDLB = 0x00001000
Dma Related Configuration :
Channel-Q is Receive
Channel-I is Transmit
Line_Count = 1;
Byte_Count = 4096;
Line_Offset_Count = 0;
When we run the Upp with the above Configuration settings in Arm1810, In Inturrept routine continiously Underrun or Overflow Inturrept related to Channel-I are getting, But data corruption is not happening(Data size is 4k(4096)).
The following output as shown below:
TxBuff b b b
RxBuff
bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
Underrun or Overflow Inturrept Occured for Channel- I
TxBuff c c c
RxBuff
cccccccccccccccccccccccccccccccc
cccccccccccccccccccccccccccccccc
cccccccccccccccccccccccccccccccc
cccccccccccccccccccccccccccccccc
cccccccccccccccccccccccccccccccc
cccccccccccccccccccccccccccccccc
Underrun or Overflow Inturrept Occured for Channel -I
2/ Channel B to A:
The same configuration parameters used & working fine.
Kindly let us known your feedback/ suggestions for Channel A to B issue for Underrun or Overflow Inturrept Occuring.