Datasheet

dsPIC33EPXXXGP50X, dsPIC33EPXXXMC20X/50X AND PIC24EPXXXGP/MC20X
DS70000657H-page 142  2011-2013 Microchip Technology Inc.
REGISTER 8-1: DMAXCON: DMA CHANNEL X CONTROL REGISTER
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 U-0 U-0 U-0
CHEN SIZE DIR HALF NULLW — — —
bit 15 bit 8
U-0 U-0 R/W-0 R/W-0 U-0 U-0 R/W-0 R/W-0
— — AMODE1 AMODE0 — —MODE1MODE0
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 15 CHEN: DMA Channel Enable bit
1 = Channel is enabled
0 = Channel is disabled
bit 14 SIZE: DMA Data Transfer Size bit
1 =Byte
0 =Word
bit 13 DIR: DMA Transfer Direction bit (source/destination bus select)
1 = Reads from RAM address, writes to peripheral address
0 = Reads from peripheral address, writes to RAM address
bit 12 HALF: DMA Block Transfer Interrupt Select bit
1 = Initiates interrupt when half of the data has been moved
0 = Initiates interrupt when all of the data has been moved
bit 11 NULLW: Null Data Peripheral Write Mode Select bit
1 = Null data write to peripheral in addition to RAM write (DIR bit must also be clear)
0 = Normal operation
bit 10-6 Unimplemented: Read as ‘0’
bit 5-4 AMODE<1:0>: DMA Channel Addressing Mode Select bits
11 = Reserved
10 = Peripheral Indirect Addressing mode
01 = Register Indirect without Post-Increment mode
00 = Register Indirect with Post-Increment mode
bit 3-2 Unimplemented: Read as ‘0’
bit 1-0 MODE<1:0>: DMA Channel Operating Mode Select bits
11 = One-Shot, Ping-Pong modes are enabled (one block transfer from/to each DMA buffer)
10 = Continuous, Ping-Pong modes are enabled
01 = One-Shot, Ping-Pong modes are disabled
00 = Continuous, Ping-Pong modes are disabled