Enhanced Direct Memory Access (eDMA)
MPC5606S Microcontroller Reference Manual, Rev. 7
518
Freescale Semiconductor
14. DMA engine writes: TCD.saddr = 0x1000, TCD.daddr = 0x2000, TCD.citer = 2 (TCD.biter)
15. DMA engine writes: TCD.active = 0, TCD.done = 1, DMAINT[n] = 1
16. The channel retires
major loop complete
The DMA goes idle or services the next channel.
15.5.5
TCD status
15.5.5.1
Minor loop complete
There are two methods to test for minor loop completion when using software initiated service requests.
The first method is to read the TCD.citer field and test for a change. Another method may be extracted
from the sequence shown below. The second method is to test the TCD.start bit AND the TCD.active bit.
The minor loop complete condition is indicated by both bits reading zero after the TCD.start was written
to a one. Polling the TCD.active bit may be inconclusive because the active status may be missed if the
channel execution is short in duration.
The TCD status bits execute the following sequence for a software activated channel:
1. TCD.start = 1, TCD.active = 0, TCD.done = 0 (channel service request via software)
2. TCD.start = 0, TCD.active = 1, TCD.done = 0 (channel is executing)
3. TCD.start = 0, TCD.active = 0, TCD.done = 0 (channel has completed the minor loop and is idle)
or
TCD.start = 0, TCD.active = 0, TCD.done = 1 (channel has completed the major loop and is idle)
The best method to test for minor loop completion when using hardware initiated service requests is to
read the TCD.citer field and test for a change. The hardware request and acknowledge handshakes signals
are not visible in the programmer’s model.
The TCD status bits execute the following sequence for a hardware activated channel:
1. ipd_req asserts (channel service request via hardware)
2. TCD.start = 0, TCD.active = 1, TCD.done = 0 (channel is executing)
3. TCD.start = 0, TCD.active = 0, TCD.done = 0 (channel has completed the minor loop and is idle)
or
TCD.start = 0, TCD.active = 0, TCD.done = 1 (channel has completed the major loop and is idle)
For both activation types, the major loop complete status is explicitly indicated via the TCD.done bit.
The TCD.start bit is cleared automatically when the channel begins execution regardless of how the
channel was activated.
15.5.5.2
Active channel TCD reads
The DMA will read back the 'true' TCD.saddr, TCD.daddr, and TCD.nbytes values if read while a channel
is executing. The 'true' values of the saddr, daddr, and nbytes are the values the DMA engine is currently
using in its internal register file and not the values in the TCD local memory for that channel. The
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...
Страница 1324: ...Register Map MPC5606S Microcontroller Reference Manual Rev 7 1322 Freescale Semiconductor...