Chrom-Art Accelerator™ controller (DMA2D) RM0090
358/1749 RM0090 Rev 18
11.5.8 DMA2D foreground PFC control register (DMA2D_FGPFCCR)
Address offset: 0x001C
Reset value: 0x0000 0000
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
ALPHA[7:0]
Reserved
AM[1:0]
rw rw rw rw rw rw rw rw rw rw
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
CS[7:0]
Reserved
START CCM CM[3:0]
rw rw rw rw rw rw rw rw rs rw rw rw rw rw
Bits 31:24 ALPHA[7: 0]: Alpha value
These bits define a fixed alpha channel value which can replace the original alpha value
or be multiplied by the original alpha value according to the alpha mode selected
through the AM[1:0] bits.
These bits can only be written when data transfers are disabled. Once a transfer has
started, they become read-only.
Bits 23:18 Reserved, must be kept at reset value
Bits 17:16 AM[1: 0]: Alpha mode
These bits select the alpha channel value to be used for the foreground image. They
can only be written data the transfer are disabled. Once the transfer has started, they
become read-only.
00: No modification of the foreground image alpha channel value
01: Replace original foreground image alpha channel value by ALPHA[7: 0]
10: Replace original foreground image alpha channel value by ALPHA[7:0] multiplied
with original alpha channel value
other configurations are meaningless
Bits 15:8 CS[7: 0]: CLUT size
These bits define the size of the CLUT used for the foreground image. Once the CLUT
transfer has started, this field is read-only.
The number of CLUT entries is equal to CS[7:0] + 1.
Bits 7:6 Reserved, must be kept at reset value