Enhanced Direct Memory Access Controller (eDMA)
21-36
Freescale Semiconductor
PXR40 Microcontroller Reference Manual, Rev. 1
NOTE
The TCD structures for the eDMA channels shown in
implemented in internal SRAM. These structures are not initialized at reset;
therefore, all channel TCD parameters must be initialized by the application
code before activating that channel.
Table 21-21. TCDn Field Descriptions
Field
Description
0–31 /
0x0 [0:31]
SADDR
Source address. Memory address pointing to the source data.
Word 0x0, bits 0–31.
32–36 /
0x4 [0:4]
SMOD
Source address modulo.
0
Source address modulo feature is disabled.
non-0 This value defines a specific address range that is specified to be the value after
SADDR + SOFF calculation is performed or the original register value. The setting of
this field provides the ability to easily implement a circular data queue. For data queues
requiring power-of-2 size bytes, the queue should start at a 0-modulo-size address and
the SMOD field should be set to the appropriate value for the queue, freezing the
desired number of upper address bits. The value programmed into this field specifies
the number of lower address bits that are allowed to change. For this circular queue
application, the SOFF is typically set to the transfer size to implement post-increment
addressing with the SMOD function constraining the addresses to a 0-modulo-size
range.
37–39 /
0x4 [5:7]
SSIZE
Source data transfer size.
000 8-bit
001 16-bit
010 32-bit
011 64-bit
100 Reserved
101 32-byte (64-bit, 4 beat, WRAP4 burst)
110 Reserved
111 Reserved
The attempted specification of a reserved encoding causes a configuration error.
40–44 /
0x4 [8:12]
DMOD
Destination address modulo. See the SMOD[0:5] definition.
45–47 /
0x4 [13:15]
DSIZE
Destination data transfer size. See the SSIZE[0:2] definition.
48–63 /
0x4 [16:31]
SOFF
Source address signed offset. Sign-extended offset applied to the current source address to
form the next-state value as each source read is completed.
64
0x8 [0]
SMLOE
1
Source minor loop offset enable
This flag selects whether the minor loop offset is applied to the source address upon minor
loop completion.
0 The minor loop offset is not applied to the saddr.
1 The minor loop offset is applied to the saddr.
Summary of Contents for PXR4030
Page 1: ...PXR40 Microcontroller Reference Manual Devices Supported PXR4030 PXR4040 PXR40RM Rev 1 06 2011...
Page 30: ...PXR40 Microcontroller Reference Manual Rev 1 Freescale Semiconductor xxx...
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Page 66: ...Memory Map PXR40 Microcontroller Reference Manual Rev 1 2 4 Freescale Semiconductor...
Page 120: ...Signal Descriptions 3 54 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Page 860: ...FlexCAN Module 24 50 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Page 1167: ...Decimation Filter Freescale Semiconductor 28 53 PXR40 Microcontroller Reference Manual Rev 1...
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