Enhanced Direct Memory Access (eDMA)
MPC5606S Microcontroller Reference Manual, Rev. 7
520
Freescale Semiconductor
3. minor loop done
set channel 12 TCD.start bit
4. minor loop done, major loop done
set channel 7 TCD.start bit
When minor loop linking is enabled (TCD.citer.e_link = 1), the TCD.citer field uses a nine bit vector to
form the current iteration count.
When minor loop linking is disabled (TCD.citer.e_link = 0), the TCD.citer field uses a 15 bit vector to form
the current iteration count. The bits associated with the TCD.citer.linkch field are concatenated onto the
citer value to increase the range of the citer.
NOTE
The TCD.citer.e_link bit and the TCD.biter.e_link bit must equal or a
configuration error will be reported. The citer and biter vector widths must
be equal to calculate the major loop, half-way done interrupt point.
15.5.7
Dynamic programming
This section provides recommended methods to change the programming model during channel execution.
15.5.7.1
Dynamic priority changing
The following two options are recommended for dynamically changing
channel
priority levels:
1. Switch to round-robin channel arbitration mode, change the channel priorities, then switch back to
fixed arbitration mode.
2. Disable all the channels within a group, then change the channel priorities within that group only,
then enable the appropriate channels.
The following two options are available for dynamically changing
group
priority levels:
1. Switch to round-robin group arbitration mode, change the group priorities, then switch back to
fixed arbitration mode.
2. Disable ALL channels, change the group priorities, then enable the appropriate channels.
15.5.7.2
Dynamic channel linking and dynamic scatter/gather
Dynamic channel linking and dynamic scatter/gather is the process of changing the TCD.major.e_link or
TCD.e_sg bits during channel execution. These bits are read from the TCD local memory at the
end
of
channel execution thus allowing the user to enable either feature during channel execution.
Because the user is allowed to change the configuration during execution, a coherency model is needed.
Consider the scenario where the user attempts to execute a dynamic channel link by enabling the
TCD.major.e_link bit at the same time the DMA engine is retiring the channel. The TCD.major.e_link
would be set in the programmer’s model, but it would be unclear whether the actual link was made before
the channel retired.
The following coherency model is recommended when executing a dynamic channel link or dynamic
scatter/gather request:
1. Set the TCD.major.e_link bit.
Содержание MPC5602S
Страница 76: ...Overview MPC5606S Microcontroller Reference Manual Rev 7 74 Freescale Semiconductor...
Страница 82: ...Memory Map MPC5606S Microcontroller Reference Manual Rev 7 80 Freescale Semiconductor...
Страница 112: ...Signal Description MPC5606S Microcontroller Reference Manual Rev 7 110 Freescale Semiconductor...
Страница 166: ...Analog to Digital Converter ADC MPC5606S Microcontroller Reference Manual Rev 7 164 Freescale Semiconductor...
Страница 182: ...Boot Assist Module BAM MPC5606S Microcontroller Reference Manual Rev 7 180 Freescale Semiconductor...
Страница 234: ...Clock Description MPC5606S Microcontroller Reference Manual Rev 7 232 Freescale Semiconductor...
Страница 286: ...Crossbar Switch XBAR MPC5606S Microcontroller Reference Manual Rev 7 284 Freescale Semiconductor...
Страница 470: ...e200z0h Core MPC5606S Microcontroller Reference Manual Rev 7 468 Freescale Semiconductor...
Страница 524: ...Enhanced Direct Memory Access eDMA MPC5606S Microcontroller Reference Manual Rev 7 522 Freescale Semiconductor...
Страница 546: ...Error Correction Status Module ECSM MPC5606S Microcontroller Reference Manual Rev 7 544 Freescale Semiconductor...
Страница 669: ...Flash Memory MPC5606S Microcontroller Reference Manual Rev 7 Freescale Semiconductor 667...
Страница 670: ...Flash Memory MPC5606S Microcontroller Reference Manual Rev 7 668 Freescale Semiconductor...
Страница 716: ...FlexCAN MPC5606S Microcontroller Reference Manual Rev 7 714 Freescale Semiconductor...
Страница 882: ...LIN Controller LINFlex MPC5606S Microcontroller Reference Manual Rev 7 880 Freescale Semiconductor...
Страница 901: ...Memory Protection Unit MPU MPC5606S Microcontroller Reference Manual Rev 7 Freescale Semiconductor 899...
Страница 902: ...Memory Protection Unit MPU MPC5606S Microcontroller Reference Manual Rev 7 900 Freescale Semiconductor...
Страница 955: ...Mode Entry Module MC_ME MPC5606S Microcontroller Reference Manual Rev 7 Freescale Semiconductor 953...
Страница 956: ...Mode Entry Module MC_ME MPC5606S Microcontroller Reference Manual Rev 7 954 Freescale Semiconductor...
Страница 1072: ...Quad Serial Peripheral Interface QuadSPI MPC5606S Microcontroller Reference Manual Rev 7 1070 Freescale Semiconductor...
Страница 1096: ...Reset Generation Module MC_RGM MPC5606S Microcontroller Reference Manual Rev 7 1094 Freescale Semiconductor...
Страница 1106: ...Real Time Clock RTC API MPC5606S Microcontroller Reference Manual Rev 7 1104 Freescale Semiconductor...
Страница 1186: ...Stepper Stall Detect SSD MPC5606S Microcontroller Reference Manual Rev 7 1184 Freescale Semiconductor...
Страница 1213: ...System Integration Unit Lite SIUL MPC5606S Microcontroller Reference Manual Rev 7 Freescale Semiconductor 1211...
Страница 1214: ...System Integration Unit Lite SIUL MPC5606S Microcontroller Reference Manual Rev 7 1212 Freescale Semiconductor...
Страница 1238: ...Voltage Regulators and Power Supplies MPC5606S Microcontroller Reference Manual Rev 7 1236 Freescale Semiconductor...
Страница 1252: ...Wakeup Unit WKPU MPC5606S Microcontroller Reference Manual Rev 7 1250 Freescale Semiconductor...
Страница 1258: ...Registers Under Protection MPC5606S Microcontroller Reference Manual Rev 7 1256 Freescale Semiconductor...
Страница 1323: ...Register Map MPC5606S Microcontroller Reference Manual Rev 7 Freescale Semiconductor 1321...
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