the arbitration size, it is possible to control exactly how many items are transferred to or from a
peripheral each time it makes a μDMA service request.
9.2.1 Channel Assignments
Each DMA channel has up to nine possible assignments which are selected using the DMA Channel
Map Select n (DMACHMAPn) registers with 4-bit assignment fields for each µDMA channel.
Table 9-1 on page 680 shows the µDMA channel mapping. The Enc. column shows the encoding
for the respective DMACHMAPn bit field. Encodings 0x9-0xF are reserved. To support legacy
software which uses the DMA Channel Assignment (DMACHASGN) register, Enc. 0 is equivalent
to a DMACHASGN bit being clear, and Enc. 1 is equivalent to a DMACHASGN bit being set. If the
DMACHASGN register is read, bit fields return 0 if the corresponding DMACHMAPn register field
value are equal to 0, otherwise they return 1 if the corresponding DMACHMAPn register field values
are not equal to 0. The Type indication in the table indicates if a particular peripheral uses a single
request (S), burst request (B) or either (SB).
Note: Channels or encodings marked as reserved cannot be used for µDMA transfers. Channels
designated in the table as only "Software" are dedicated software channels. When only one
software request is required in an application, dedicated software channels can be used.
If multiple software requests in code are required, then peripheral channel software requests
should be used for proper µDMA completion acknowledgement.
Table 9-1. μDMA Channel Assignments
Encoding
Channel
876543210
Type
Peripheral
Type
Peripheral
Type
Peripheral
Type
Peripheral
Type
Peripheral
Type
Peripheral
Type
Peripheral
Type
Peripheral
Type
Peripheral
-Reserved-ReservedSB
B
I2C0 RX-Reserved-ReservedBGPTimer
4A
-ReservedSBUART2
RX
-Reserved0
-Reserved-ReservedSB
B
I2C0 TX-Reserved-ReservedBGPTimer
4B
-ReservedSBUART2
TX
-Reserved1
-Reserved-ReservedSB
B
I2C1RX-Reserved-Reserved-Reserved-ReservedBGPTimer
3A
-Reserved2
-Reserved-ReservedSB
B
I2C1 TX-Reserved-ReservedSSoftware-ReservedBGPTimer
3B
-Reserved3
-Reserved-ReservedSB
B
I2C2 RXBSoftware-ReservedBGPIO A-ReservedBGPTimer
2A
-Reserved4
-Reserved-ReservedSB
B
I2C2 TXBSoftware-ReservedBGPIO B-ReservedBGPTimer
2B
-Reserved5
-Reserved-Reserved-ReservedBSoftwareSB
B
I2C0 RXBGPIO CSBUART5
RX
BGPTimer
2A
-Reserved6
-Reserved-Reserved-Reserved-ReservedSB
B
I2C0 TXBGPIO DSBUART5
TX
BGPTimer
2B
-Reserved7
-Reserved-Reserved-Reserved-ReservedSB
B
I2C1RXBGPTimer
5A
-ReservedSBUART1
RX
SBUART0
RX
8
-Reserved-Reserved-Reserved-ReservedSB
B
I2C1 TXBGPTimer
5B
-ReservedSBUART1
TX
SBUART0
TX
9
-ReservedBGPTimer
6A
-Reserved-ReservedSB
B
I2C2 RX-ReservedSBUART6
RX
SBSSI1 RXSBSSI0 RX10
June 18, 2014680
Texas Instruments-Production Data
Micro Direct Memory Access (μDMA)
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