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Chapter 26 DMA Controller
3.DMA Controller (DMAC) Operation
3. DMA Controller (DMAC) Operation
A DMA controller (DMAC) is built into all FR family devices. The FR family DMAC is a multi-func-
tional DMAC that controls data transfer at high speed without the use of CPU instructions.
This section describes the operation of the DMAC.
■
Principal Operations
•
Functions can be set for each transfer channel independently.
•
Once starting has been enabled, a channel starts transfer operation only after a specified transfer request has
been detected.
•
After a transfer request is detected, a DMA transfer request is output to the bus controller and the bus right is
acquired by the bus controller before the transfer is started.
•
The transfer is carried out as a sequence conforming to the mode settings made independently for the
channel being used.
■
Transfer Mode
Each DMA channel performs transfer according to the transfer mode set by the MOD[1:0] bits of its DMACB
register.
●
Block/step transfer
Only a single block transfer unit is transferred in response to one transfer request. DMA then stops requesting the
bus controller for transfer until the next transfer request is received.
The block transfer unit is the specified block size (BLK[3:0] of DMACA).
●
Burst transfer
Transfer in response to one transfer request is carried out continuously for the number of times in the specified
transfer count is reached.
The specified transfer count is the transfer count (BLK[3:0] of DMACA X DTC[15:0] of DMACA) X block size.
●
Demand transfer
Transfer is carried out continuously until the transfer request input (detected with a level at the DREQ pin) from
an external device or a specified transfer count is reached.
The specified transfer count in a demand transfer is the specified transfer count (DTC[15:0] of DMACA). The
block size is always 1 and the register value is ignored.
■
Transfer Type
●
2-cycle transfer (normal transfer)
The DMA controller operates using a read operation and a write operation as its unit of operation.
Data is read from an address in the transfer source register and then written to another address in the transfer
destination register.
●
Fly-by transfer (memory --> I/O)
The DMA controller operates using a read operation as its unit of operation.
If DMA transfer is performed when fly-by transfer is set, DMA issues a fly-by transfer (read) request to the bus
controller and the bus controller lets the external interface carry out the fly-by transfer (read).
Summary of Contents for FR Family FR60 Lite
Page 2: ...FUJITSU LIMITED ...
Page 3: ...FR60 32 BIT MICROCONTROLLER MB91460 Series User s Manual ...
Page 15: ...xi ...
Page 16: ...xii ...
Page 38: ...22 Chapter 2 MB91460 Rev A Rev B Overview 4 Block Diagram ...
Page 128: ...112 Chapter 4 CPU Architecture 9 Addressing ...
Page 153: ...137 Chapter 8 Device State Transition 3 State Transition Diagram ...
Page 154: ...138 Chapter 8 Device State Transition 3 State Transition Diagram ...
Page 169: ...153 Chapter 9 Reset 10 Caution ...
Page 170: ...154 Chapter 9 Reset 10 Caution ...
Page 180: ...164 Chapter 10 Standby 7 Q A ...
Page 182: ...166 Chapter 10 Standby 8 Caution ...
Page 199: ...183 Chapter 12 Instruction Cache 2 Main body structure Figure 2 3 I Cache Address Map ...
Page 200: ...184 Chapter 12 Instruction Cache 2 Main body structure Figure 2 4 I Cacheable Area ...
Page 222: ...206 Chapter 13 Clock Control 8 Caution ...
Page 232: ...216 Chapter 14 PLL Interface 7 Caution ...
Page 236: ...220 Chapter 15 CAN Clock Prescaler 3 Registers ...
Page 288: ...272 Chapter 19 Timebase Timer 8 Caution ...
Page 314: ...298 Chapter 22 Main Oscillation Stabilisation Timer 8 Caution ...
Page 326: ...310 Chapter 23 Sub Oscillation Stabilisation Timer 8 Caution ...
Page 348: ...332 Chapter 25 External Interrupt 8 Caution ...
Page 398: ...382 Chapter 26 DMA Controller 6 DMA External Interface ...
Page 402: ...386 Chapter 27 Delayed Interrupt 8 Caution ...
Page 412: ...396 Chapter 28 Bit Search 8 Caution ...
Page 521: ...505 Chapter 30 I O Ports 3 Port Register Settings ...
Page 522: ...506 Chapter 30 I O Ports 3 Port Register Settings ...
Page 574: ...558 Chapter 31 External Bus 4 Endian and Bus Access Byte Access ...
Page 628: ...612 Chapter 31 External Bus 13 Notes on Using the External Bus Interface ...
Page 706: ...690 Chapter 33 I2C Controller 4 Programming Flow Charts ...
Page 748: ...732 Chapter 34 CAN Controller 4 CAN Application ...
Page 762: ...746 Chapter 35 Free Run Timer 8 Caution ...
Page 790: ...774 Chapter 37 Output Compare 8 Caution ...
Page 838: ...822 Chapter 39 Programmable Pulse Generator 8 Caution ...
Page 850: ...834 Chapter 40 Pulse Frequency Modulator 4 PFM Operation and Setting ...
Page 886: ...870 Chapter 42 Sound Generator 3 Registers ...
Page 900: ...884 Chapter 43 Stepper Motor Controller 4 Caution ...
Page 939: ...923 Chapter 47 LCD Controller 3 Configuration Figure 3 2 Register List ...
Page 943: ...927 Chapter 47 LCD Controller 4 Registers Correspondence between VRAM and Common Segment Pins ...
Page 964: ...948 Chapter 48 Clock Monitor 8 Caution ...
Page 994: ...978 Chapter 51 Low Voltage Reset Interrupt 3 Registers ...
Page 998: ...982 Chapter 52 Regulator Control 3 Registers ...
Page 1008: ...992 Chapter 53 Fixed Mode Reset Vector BOOT ROM 5 Bootloader Update Strategy ...
Page 1024: ...1008 Chapter 54 Flash Memory 8 Caution ...
Page 1032: ...1016 Chapter 55 Flash Security 4 Register ...
Page 1034: ...1018 Chapter 56 Electrical Specification ...
Page 1035: ...FR60 MB91460 Series Hardware Manual European Microcontroller Design Centre Author MBo ...
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