Datasheet

www.tektronix.com/oscilloscopes 15
Debugging Serial Buses in Embedded System Designs
We can also copy the oscilloscope trigger settings to be the
search criteria for Wave Inspector. Wave Inspector will search
through the entire acquisition looking for every instance of a
NAK. In this case, Wave Inspector found 11 NAKs. The first
NAK is at the trigger position and the other 10 NAKs are after
the trigger. All NAKs are in response to the computer host
resending the IN token. Each NAK is easily viewed by using
Wave Inspector next and previous front-panel buttons to jump
to each marked NAK.
Available USB triggering capability includes the following
types:
SYNC
Reset
Suspend
Resume
End of Packet (EOP)
Token (Address) Packet
– SETUP, IN, OUT and SOF
Data Packet
– Any data value, DATA0, DATA1, DATA2 or MDATA
– Data matching with up to 16 data bytes of pattern
Handshake packets
– Any handshake value, or ACK, NAK, STALL, or NYET
Special packets
– Reserved, PRE, or ERR, SPLIT, or PING
Error types include PID Check Bits, Token CRC5, Data
CRC16 or Bit stuffing
Wave Inspector can also search on all of the same criteria
used for triggering.
With Tektronix oscilloscopes, you can easily capture and
analyze USB 2.0 signals, protocol, and data and then
correlate them to other analog and digital signals to provide
you with complete design visibility.
Figure 23. Decoded High-speed USB 2.0 waveform captured with serial triggering on
an MSO5204 with option SR-USB.