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Increment mode
The increment mode of peripheral and memory is controlled through PERIM
and MEMIM bits of DMA_SCFG register. When both bits are set to 1, it is
configured as the increment mode and the increment is the value of
PERSIZECFG and MENSIZECFG bits of DMA_SCFG register. The
PERSIZECFG and MENSIZECFG bits are used to set the data size of
peripheral and memory to byte, half word or word.
Single transmission and burst mode
Burst transmission refers to the high-speed transmission that increases the data
volume transmitted each time at the transmission stage so as to improve the
transmission speed. In the process of burst transmission, AHB bus will be
occupied.
Single and burst transmissions can be controlled through the PBCFG and
MBCFG bits of DMA_SCFG register, and it can be configured as single
transmission, incremental burst transmission of 4 ticks, incremental burst
transmission of 8 ticks and incremental burst transmission of 16 ticks. This
increment is determined by the value of PERSIZECFG and MENSIZECFG bits.
The burst mode can be enabled only when the increment mode is supported.
The burst mode shall be used in combination with FIFO, and the selected FIFO
threshold shall be suitable for the burst size of memory, as shown in the table
below.
Table 51 FIFO Threshold Configuration
MENSIZECFG
FIFO
threshold
MBCFG=01
MBCFG=10
MBCFG=11
Byte
1/4
One-time burst of 4
ticks
Disable
Disable
1/2
Two-time burst of 4
ticks
One-time burst of 8
ticks
3/4
Three-time burst of 4
ticks
Disable
Full
Four-time burst of 4
ticks
Two-time burst of 8
ticks
One-time burst of 16
ticks
Half word
1/4
Disable
Disable
Disable
1/2
One-time burst of 4
ticks
3/4
Disable
Full
Two-time burst of 4
ticks
One-time burst of 8
ticks
Word
1/4
Disable
Disable