MC9S12HY64 Datasheet, PDF (222/792 Pages) Freescale Semiconductor, Inc – S12 Microcontrollers

S12S Debug Module (S12SDBGV2)
This however violates the S12SDBGV1 specification, which states that a match leading to final state
always has priority in case of a simultaneous match, whilst priority is also given to the lowest channel
number. For S12SDBG the corresponding CPU priority decoder is removed to support this, such that on
simultaneous taghits, taghits pointing to final state have highest priority. If no taghit points to final state
then the lowest channel number has priority. Thus with the above encoding from State3, the CPU and DBG
would break on a simultaneous M0/M2.
6.5.6 Scenario 5
Trigger if following event A, event C precedes event B. i.e. the expected execution flow is A->B->C.
Figure 6-34. Scenario 5
SCR1=0011
SCR2=0110
State1
M1
State2
M0
M2
Final State
Scenario 5 is possible with the S12SDBGV1 SCR encoding
6.5.7 Scenario 6
Trigger if event A occurs twice in succession before any of 2 other events (BC) occurs. This scenario is
not possible using the S12SDBGV1 SCR encoding. S12SDBGV2 includes additions shown in red. The
change in SCR1 encoding also has the advantage that a State1->State3 transition using M0 is now possible.
This is advantageous because range and data bus comparisons use channel0 only.
Figure 6-35. Scenario 6
SCR1=1001
State1
SCR3=1010
M0
State3
M0
M12
Final State
6.5.8 Scenario 7
Trigger when a series of 3 events is executed out of order. Specifying the event order as M1,M2,M0 to run
in loops (120120120). Any deviation from that order should trigger. This scenario is not possible using the
MC9S12HY/HA-Family Reference Manual, Rev. 1.04
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