Convolutional Encoder COM-1010 -> Convolutional Decoder COM-1015 -> BER measurement COM-1005.  

Test configuration example: 
 - 1.33 Mbit/s Set by internal NCO in Convolutional Encoder. 
 - Rate 1/3 Encoding/Decoding
 - Hard Decision 

Back to back Convolutional Encoder/Decoder test. A periodic 2047-bit sequence is generated by the COM1010 
and used as the input to the rate 1/3 encoder. 
The end to end BER is measured using the COM-1005 module. Zero bit errors are expected. 


Proper operation can be verified as follows:
(a) import the 1010_1015_1005.stn settings into the assembly, using the
ComBlock Control Center file | import menu. 

(b) using an oscilloscope probe:


COM-1005 TP1 is high, indicating synchronization with the 2047-bit periodic test pattern 

COM-1005 TP3 is always zero, indicating zero bit errors

COM-1010 TP5 shows regular periodic start of frame pulses every 2047 bits = 1.5 ms.
Trigger on COM-1010 TP5, and compare decoded bits (COM-1005 TP5) with the 
transmitted bits (COM-1010 TP2). The bits should be identical, taking into a 36-bit delay 
which at this data rate will be ~30 us.  

(c) from the ComBlock control center check:

The Viterbi Lock Status (COM-1015 status, REG4 bit 0)
It will show 0x01 for "In Lock."

The BER (COM-1005 status).
It will show bit errors =  0x0000.