READI Module
MPC561/MPC563 Reference Manual, Rev. 1.2
Freescale Semiconductor
24-57
NOTE
If multiple trace messages need to be queued at the same time, program trace
messages have a higher priority for queue entry than data trace messages,
unless the data trace buffers are full, in which case the data trace messages
are given temporary higher priority than the program trace messages.
24.9.8
Throughput and Latency
24.9.8.1
Assumptions for Throughput Analysis
•
All accesses are data trace only
•
56-MHz operation
•
Output signals are always free (not in middle of transmission) when requested
•
Relative Address field for data trace messages is 20 bits
•
Data field for data trace messages is 32 bits
•
One idle clock between data trace messages
24.9.8.2
Throughput Calculations
The data (read or write) trace message is 58 bits (6 [TCODE] + 20 [Relative address] + 32 [Data]).
Data trace messages are transmitted out via the MDO signals. Hence it will take eight clocks (58 bits/8
MDO signals) to send a message. There will be one idle clock before the next data trace message can be
sent.
At 56 MHz, it will take 161ns ((8+1) x 17.8) to transmit the message.
Therefore, the average number of data trace messages that can be transmitted out is 6.2 million (1/161ns)
per second, or 24.8 million bytes of read/write data per second.
24.9.9
Data Timing Diagrams
Figure 24-50. Date Write Message
TCODE = 5
Relative address = 0x318
Data = 0x4A
Don’t care data
(idle clock)
MCKO
MSEO
MDO[7:0]
00000101
11000110
01001010
00000000
00000000
Summary of Contents for MPC561
Page 84: ...MPC561 MPC563 Reference Manual Rev 1 2 lxxxiv Freescale Semiconductor...
Page 144: ...Signal Descriptions MPC561 MPC563 Reference Manual Rev 1 2 2 46 Freescale Semiconductor...
Page 206: ...Central Processing Unit MPC561 MPC563 Reference Manual Rev 1 2 3 62 Freescale Semiconductor...
Page 302: ...Reset MPC561 MPC563 Reference Manual Rev 1 2 7 14 Freescale Semiconductor...
Page 854: ...Time Processor Unit 3 MPC561 MPC563 Reference Manual Rev 1 2 19 24 Freescale Semiconductor...
Page 968: ...Development Support MPC561 MPC563 Reference Manual Rev 1 2 23 54 Freescale Semiconductor...
Page 1144: ...Internal Memory Map MPC561 MPC563 Reference Manual Rev 1 2 B 34 Freescale Semiconductor...
Page 1212: ...TPU3 ROM Functions MPC561 MPC563 Reference Manual Rev 1 2 D 60 Freescale Semiconductor...
Page 1216: ...Memory Access Timing MPC561 MPC563 Reference Manual Rev 1 2 E 4 Freescale Semiconductor...