196
Chapter 7
DMA Functions (DMA Controller)
Preliminary User’s Manual U15839EE1V0UM00
7.11 Forcible
Termination
In addition to the forcible interruption operation by means of the NMI input, DMA transfer can be forcibly
terminated by the INITn bit of the DCHCn register. The following is an example of the operation of a for-
cible termination.
Figure 7-28, “DMA Transfer Forcible Termination Example 1,” on page 196 shows a block transfer of
channel 3 which begins during the DMA block transfer of DMA channel 2. The block transfer of DMA
channel 2 is forcibly terminated by setting the INIT2 bit of its DCHC2 control register.
Figure 7-28:
DMA Transfer Forcible Termination Example 1
Remarks: 1. The next condition can be set even during DMA transfer because the DSAn, DDAn, and
DBCn registers are buffered registers. However, the setting to the DADCn register is
invalid (refer to 7.3 Next Address Setting Function and 7.2.4 DMA
control registers 0 to 3 (DADC0 to DADC3)).
2. n = 0 to 3
DMA Transfer
Request CH2
DMA Transfer
Request CH3
CPU
DMA3
DMA3
DMA3 DMA3 CPU
CPU
CPU
CPU
CPU
DMA2
DMA2
DMA2
DMA2 DMA2
CPU
CPU
EN3 bit = 1
TC3 bit = 0
EN3 bit
0
TC3 bit
1
Set register
EN2 bit = 1
TC2 bit = 0
Set register
Set register
EN2 bit
0
TC2 bit = 0
DMA channel 3 terminal count
DMA channel 3 transfer begins
DMA channel 2 transfer is forcibly terminated
and the bus is released
DSAL2, DSAH2,
DDAL2, DDAH2
DSAL3, DSAH3,
DDAL3, DDAH3
DCHC2
(INIT2 bit = 1)
→
→
→
Содержание mPD703128
Страница 6: ...6 Preliminary User s Manual U15839EE1V0UM00 ...
Страница 20: ...20 Preliminary User s Manual U15839EE1V0UM00 ...
Страница 32: ...32 Preliminary User s Manual U15839EE1V0UM00 MEMO ...
Страница 154: ...154 Preliminary User s Manual U15839EE1V0UM00 MEMO ...
Страница 238: ...238 Preliminary User s Manual U15839EE1V0UM00 MEMO ...
Страница 356: ...356 Preliminary User s Manual U15839EE1V0UM00 MEMO ...
Страница 522: ...522 Preliminary User s Manual U15839EE1V0UM00 MEMO ...
Страница 600: ...600 Preliminary User s Manual U15839EE1V0UM00 MEMO ...
Страница 610: ...610 Preliminary User s Manual U15839EE1V0UM00 ...
Страница 612: ......