PCDIDE COMPILER Custom Computer Services Inc (CCS), PCDIDE COMPILER Datasheet - Page 79

• Manufacturer Part Number: PCDIDE COMPILER
• Description: PCD C-COMPILER PIC24, DSPIC
• Manufacturer: Custom Computer Services Inc (CCS)
• Type: Compilerr

Specifications of PCDIDE COMPILER

• For Use With/related Products: Microchip PIC24/dsPIC®
• Lead Free Status / RoHS Status: Not applicable / Not applicable
• Other names: 429-1008

DMA
The Direct Memory Access (DMA) controller facilitates the transfer of data between the CPU and
its peripherals without the CPU's assistance. The transfer takes place between peripheral data
registers and data space RAM. The module has 8 channels and since each channel is
unidirectional, two channels must be allocated to read and write to a peripheral. Each DMA channel
can move a black of up to 1024 data elements after it generates an interrupt to the CPU to indicate
that the lock is available for processing. Some of the key features of the DMA module are:
Relevant Functions:
setup_dma(channel, peripheral,mode)
dma_start(channel, mode,address)
dma_status(channel)
Relevant Preprocessor:
None
Relevant Interrupts :
#INT_DMAX
Relevant Include Files:
None, all functions built-in
Relevant getenv() parameters:
None
Example Code:
setup_dma(1,DMA_IN_SPI1,DMA_BYTE);
dma_start(1, DMA_CONTINOUS|
DMA_PING_PONG, 0x2000);
· Eight DMA Channels.
· Byte or word transfers.
· CPU interrupt after half or full block transfer complete.
· One-Shot or Auto-Repeat block transfer modes.
· Ping-Pong Mode (automatic switch between two DSPRAM start addresses after each block
transfer is complete).
Configures the DMA module to copy data from the
specified peripheral to RAM allocated for the DMA
channel.
Starts the DMA transfer for the specified channel in
the specified mode of operation.
This function will return the status of the specified
channel in the DMA module.
Interrupt on channel X after DMA block or half block
transfer.
Setup channel 1 of the DMA module to read the
SPI1 channel in byte mode.
Start the DMA channel with the DMA RAM address
of 0x2000
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