Update TPIU baud rate with results from testing

Results from testing what can be written within a 20kHz cycle without
blocking match pretty well with what will completely fill the bus.

Change-Id: I0e4a032de4acc134b0c9fd8ae9cfe2b18d12aa05
diff --git a/motors/core/itm.cc b/motors/core/itm.cc
index ce2aa08..3405881 100644
--- a/motors/core/itm.cc
+++ b/motors/core/itm.cc
@@ -7,8 +7,9 @@
 namespace itm {
 namespace {
 
-constexpr int kDesiredTraceFrequency = 128000;
-// TODO(Brian): Is this actually the frequency our parts use?
+// 480000 works for a bit but eventually errors out with an stlink-v2 and
+// FRDM-K64F dev board. 200000 works for longer, but still fails eventually.
+constexpr int kDesiredTraceFrequency = 192000;
 constexpr int kTpiuAsynchronousClockFrequency = F_CPU;
 
 }  // namespace
diff --git a/motors/print/itm.h b/motors/print/itm.h
index 99f9970..1ff0bd1 100644
--- a/motors/print/itm.h
+++ b/motors/print/itm.h
@@ -12,7 +12,7 @@
 //
 // To decode the output from this, use motors/print/itm_read.py.
 // To configure openocd to feed data to that:
-//   tpiu config internal /tmp/itm.fifo uart off 120000000 64000
+//   tpiu config internal /tmp/itm.fifo uart off 120000000 192000
 class ItmPrinting final : public PrintingImplementation {
  public:
   ItmPrinting();