Freescale Semiconductor MC9S12ZVHL32, Reference Manual

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Chapter 6 S12Z Debug (S12ZDBGV2) Module
S12ZVHY/S12ZVHL Family Reference Manual Rev. 1.05
Freescale Semiconductor 225
transmission of the INFO byte starts when a line is complete. Whole bytes are always transmitted. The
grey shaded bytes of
Table 6-58 are not transmitted.
Figure 6-32. INFO byte encoding
Table 6-59. Profiling Format Encoding
6.4.6.4 Direct COF Compression
Each branch COF is stored to the trace buffer as a single bit (0=branch not taken, 1=branch taken) until an
indirect COF (indexed jump, return, or interrupt) occurs. The branch COF entries are stored in the byte
fields labelled “Direct” in
Table 6-58 . These entries start at byte1[0] and continue through to byte4[7], or
until an indirect COF occurs, whichever occurs sooner. The entries use a format whereby the left most
asserted bit is always the stop bit, which indicates that the bit to its right is the first direct COF and byte1[0]
is the last COF that occurred before the indirect COF. This is shown in
Table 6-60 , whereby the Bytes 4 to
1 of the trace buffer are shown for 3 different cases. The stop bit field for each line is shaded.
In line0, the left most asserted bit is Byte4[7]. This indicates that all remaining 31 bits in the 4-byte field
contain valid direct COF information, whereby each 1 represents branch taken and each 0 represents
branch not taken. The stop bit of line1 indicates that all 30 bits to it’s right are valid, after the 30th direct
COF entry, an indirect COF occurred, that is stored in bytes 7 to 5. In this case the bit to the left of the stop
bit is redundant. Line2 indicates that an indirect COF occurred after 8 direct COF entries. The indirect COF
address is stored in bytes 7 to 5. All bits to the left of the stop bit are redundant.
7 6 5 4 3 2 1 0
0 TSOVF TBOVF TERM Line Format
INFO[3:0] Line Format Source Description
0000 PTS CPU Initial CPU entry
0001 PTIB CPU Indexed jump with up to 31 direct COFs
0010 PTHF CPU 31 direct COFs without indirect COF
0011 PTVB CPU Vector with up to 31 direct COFs
0111 PTW CPU Error (Error codes in INFO[7:4])
Others Reserved CPU Reserved
INFO[7:4] Bit Name Description
INFO[7] Reserved CPU Reserved
INFO[6] TSOVF CPU Timestamp Overflow
INFO[5] TBOVF CPU Trace Buffer Overflow
INFO[4] TERM CPU Profiling terminated by disarming
Vector[7:0] Vector[7:0] CPU Device Interrupt Vector Address [8:1]