
Universal Serial Bus Interface – On-The-Go Module
21-76
Freescale Semiconductor
Split State Machines
The start and complete-split operational model differs from EHCI slightly because there is no bus medium
between the EHCI controller and the embedded transaction translator. Where a start or complete-split
operation would occur by requesting the split to the HS hub, the start/complete-split operation is simple
an internal operation to the embedded transaction translator.
summarizes the conditions where
handshakes are emulated from internal state instead of actual handshakes to HS split bus traffic.
Asynchronous Transaction Scheduling and Buffer Management
The following USB 2.0 specification items are implemented in the embedded Transaction Translator:
•
USB 2.0 – 11.17.3
— Sequencing is provided and a packet length estimator ensures no full-/low-speed packet
babbles into SOF time.
•
USB 2.0 – 11.17.4
— • Transaction tracking for 2 data pipes.
•
USB 2.0 – 11.17.5
— • Clear_TT_Buffer capability provided though the use of the TTCTRL register.
Periodic Transaction Scheduling and Buffer Management
The following USB 2.0 specification items are implemented in the embedded transaction translator:
•
USB 2.0 – 11.18.6.[1-2]
— Abort of pending start-splits
– EOF (and not started in microframes 6)
– Idle for more than 4 microframes
— Abort of pending complete-splits
– EOF
– Idle for more than 4 microframes
•
USB 2.0 - 11.18.[7-8]
— Transaction tracking for up to 4 data pipes.
Table 21-62. Emulated Handshakes
Condition Emulate
TT
Response
Start-Split: All asynchronous buffers full
NAK
Start-Split: All periodic buffers full
ERR
Start-Split: Success for start of async. transaction
ACK
Start-Split: Start periodic transaction
No handshake (Ok)
Complete-Split: Failed to find transaction in queue
Bus time-out
Complete-Split: Transaction in queue is busy
NYET
Complete-Split: Transaction in queue is complete
Actual handshake from FS/LS device
MCF5329 Reference Manual, Rev 3
Содержание MCF5329
Страница 106: ...ColdFire Core 3 32 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 126: ...Enhanced Multiply Accumulate Unit EMAC 4 20 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 148: ...Cache 5 22 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 154: ...Static RAM SRAM 6 6 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 184: ...Power Management 8 18 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 204: ...Reset Controller Module 10 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 220: ...System Control Module SCM 11 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 228: ...Crossbar Switch XBS 12 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 268: ...General Purpose I O Module 13 40 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 392: ...SDRAM Controller SDRAMC 18 30 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 436: ...Fast Ethernet Controller FEC 19 44 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 564: ...Liquid Crystal Display Controller LCDC 22 44 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 594: ...FlexCAN 23 30 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 678: ...Pulse Width Modulation PWM Module 26 22 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 684: ...Watchdog Timer Module 27 6 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 692: ...Programmable Interrupt Timers PIT0 PIT3 28 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 704: ...DMA Timers DTIM0 DTIM3 29 12 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 720: ...Queued Serial Peripheral Interface QSPI 30 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 754: ...UART Modules 31 34 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 770: ...I2 C Interface 32 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 790: ...Message Digest Hardware Accelerator MDHA 33 20 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 866: ...Debug Module 36 50 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 902: ...Register Memory Map Quick Reference A 26 Freescale Semiconductor MCF5329 Reference Manual Rev 3...