Freescale Semiconductor PXR4030, Reference Manual

Page: 1358 / 1434

Nexus Development Interface (NDI)
31-42 Freescale Semiconductor
PXR40 Microcontroller Reference Manual, Rev. 1
Traditional BTM messages maintain their temporal ordering because each event that queues a message to
the FIFO is processed and sent in the order it was generated, and the message order is maintained when it
is transmitted.
31.13.2 BTM Message Formats
The e200z7 Nexus3 module supports three types of traditional BTM messages—direct, indirect, and
synchronization messages. It supports two types of branch history BTM messages—indirect branch
history, and indirect branch history with synchronization messages. Debug status messages and error
messages are also supported.
31.13.2.1 Indirect Branch Messages (History)
Indirect branches include all taken branches whose destination is determined at run time, interrupts and
exceptions. If DC[PTM] is set, indirect branch information is messaged out in the following format:
Figure 31-16. Indirect Branch Message (History) Format
31.13.2.2 Indirect Branch Messages (Traditional)
If DC[PTM] is cleared, indirect branch information is messaged out in the following format:
Figure 31-17. Indirect Branch Message Format
31.13.2.3 Direct Branch Messages (Traditional)
Direct branches (conditional or unconditional) are all taken branches whose destination is fixed in the
instruction opcode. Direct branch information is messaged out in the following format:
HIST
msb lsb
2 3 4
U-ADDR I-CNT SRC
5
4 bits
1
TCODE (011100)
1–8 bits 1–32 bits 1–32 bits 6 bits
Max length = 82 bits; Min length = 13 bits
msb lsb
2 3 4
U-ADDR I-CNT SRC
4 bits
1
TCODE (000100)
1–8 bits 1–32 bits 6 bits
Max length = 50 bits; Min length = 12 bits