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Section 11 User Break Controller (UBC)
Rev. 4.00 Sep. 14, 2005 Page 256 of 982
REJ09B0023-0400
11.3 Operation
11.3.1
Flow of the User Break Operation
The flow from setting of break conditions to user break exception processing is described below:
1. The break addresses is set in the break address registers (BARA or BARB). The masked
addresses are set in the break address mask registers (BAMRA or BAMRB). The break data is
set in the break data register (BDRB). The masked data is set in the break data mask register
(BDMRB). The bus break conditions are set in the break bus cycle registers (BBRA or
BBRB). Three groups of BBRA or BBRB (L bus cycle/I bus cycle select, instruction
fetch/data access select, and read/write select) are each set. No user break will be generated if
even one of these groups is set with 00. The respective conditions are set in the bits of the
break control register (BRCR). Make sure to set all registers related to breaks before setting
BBRA or BBRB.
2. When the break conditions are satisfied, the UBC sends a user break request to the CPU and
sets the L bus condition match flag (SCMFCA or SCMFCB) and the I bus condition match
flag (SCMFDA or SCMFDB) for the appropriate channel. When the X/Y memory bus is
specified for channel B, SCMFCB is used for the condition match flag.
3. The appropriate condition match flags (SCMFCA, SCMFDA, SCMFCB, and SCMFDB) can
be used to check if the set conditions match or not. The matching of the conditions sets flags,
but they are not reset. 0 must first be written to them before they can be used again.
4. There is a chance that the break set in channel A and the break set in channel B occur around
the same time. In this case, there will be only one break request to the CPU, but these two
break channel match flags could be both set.
5. When selecting the I bus as the break condition, note the following:
Several bus masters, including the CPU and DMAC, are connected to the I bus. The UBC
monitors bus cycles generated by all bus masters, and determines the condition match.
Physical addresses are used for the I bus. Set a physical address in break address registers
(BARA and BARB). The upper three bits of logical addresses in the P0 to P3 area issued
by the CPU on the L bus are masked (to 0) before they are placed on the I bus. The upper
three bits of the source and destination addresses set in the DMAC are masked in the same
way. However, logical addresses in the P4 area are output unchanged on the I bus.
For data access cycles issued on the L bus by the CPU, if their logical addresses are not to
be cached, they are issued with the data size specified on the L bus.
For instruction fetch cycles issued on the L bus by the CPU, even though their logical
addresses are not to be cached, they are issued in longwords and their addresses are
rounded to match longword boundaries.
Summary of Contents for HD6417641
Page 2: ...Rev 4 00 Sep 14 2005 Page ii of l...
Page 7: ...Rev 4 00 Sep 14 2005 Page vii of l...
Page 11: ...Rev 4 00 Sep 14 2005 Page xi of l USB Universal serial bus WDT Watch dog timer...
Page 12: ...Rev 4 00 Sep 14 2005 Page xii of l...
Page 28: ...Rev 4 00 Sep 14 2005 Page xxviii of l...
Page 204: ...Section 4 Clock Pulse Generator CPG Rev 4 00 Sep 14 2005 Page 154 of 982 REJ09B0023 0400...
Page 212: ...Section 5 Watchdog Timer WDT Rev 4 00 Sep 14 2005 Page 162 of 982 REJ09B0023 0400...
Page 228: ...Section 6 Power Down Modes Rev 4 00 Sep 14 2005 Page 178 of 982 REJ09B0023 0400...
Page 246: ...Section 8 X Y Memory Rev 4 00 Sep 14 2005 Page 196 of 982 REJ09B0023 0400...
Page 318: ...Section 11 User Break Controller UBC Rev 4 00 Sep 14 2005 Page 268 of 982 REJ09B0023 0400...
Page 454: ...Section 12 Bus State Controller BSC Rev 4 00 Sep 14 2005 Page 404 of 982 REJ09B0023 0400...
Page 504: ...Section 14 U Memory Rev 4 00 Sep 14 2005 Page 454 of 982 REJ09B0023 0400...
Page 566: ...Section 17 Compare Match Timer CMT Rev 4 00 Sep 14 2005 Page 516 of 982 REJ09B0023 0400...
Page 868: ...Section 21 A D Converter Rev 4 00 Sep 14 2005 Page 818 of 982 REJ09B0023 0400...
Page 914: ...Section 23 I O Ports Rev 4 00 Sep 14 2005 Page 864 of 982 REJ09B0023 0400...
Page 956: ...Section 24 List of Registers Rev 4 00 Sep 14 2005 Page 906 of 982 REJ09B0023 0400...
Page 1016: ...Section 25 Electrical Characteristics Rev 4 00 Sep 14 2005 Page 966 of 982 REJ09B0023 0400...
Page 1024: ...Appendix Rev 4 00 Sep 14 2005 Page 974 of 982 REJ09B0023 0400...
Page 1032: ...Rev 4 00 Sep 14 2005 Page 982 of 982 REJ09B0023 0400 X X Y data addressing 52 X Y memory 193...
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