SAM4L Datasheet, PDF (1036/1185 Pages) ATMEL Corporation – ATSAM ARM-based Flash MCU

ATSAM4L4/L2
Up to eight segments can be selected individually to blink. Each bit in Blink Segment Selection x
field (BCFG.BSSx) selects a segment for blinking. If BSS0[y]=1, segment connected to
SEG0/COMy is selected to blink. If BSS1[y]=1, segment connected to SEG1/COMy is selected
to blink.
A segment will blink if its corresponding bit is one in the display memory, otherwise it remains
OFF.
The blink frequency is defined by the number of frames (FCx in TIM register) between each
state ON/OFF. So after FCx+1 frames, the segment will change state. Note that blinking fre-
quency is also related to waveform mode, see ”Waveform Modes” on page 1033.
The frame counter is selected by writing its number in BCFG.FCS field. BCFG.BSSx and
BCFG.MODE should be modified after a frame has ended (SR.FC0R=1), BCFG.FCS shall not
be modified when blinking is running.
The blinking is started by writing a one to CR.BSTART and stopped by writing a one to
CR.BSTOP. The status of blinking can be read in SR.BLKS.
Table 39-6.
BLANK
1
0
0
Blinking Modes
EN
BSS1[3:0] BSS0[3:0]
x
xxxx xxxx
0
xxxx xxxx
0000 0000
1
Not equal to zero
Comment
All segments are OFF
All segments are driven by the display memory
All segments are blinking at the blink frequency
Selected segment(s) are blinking at the blink
frequency
39.6.9
Autonomous Segment Animation
Up to eight pixels can be animated by an internal circular shift register. Up to eight states are
then defined to make a running wheel for example. The number of segments used for animation
must be written in SIZE field in Circular Shift Register Configuration (CSRCFG). If SIZE=N, cir-
cular shift register uses bits 0 to N-1.
The circular shift register bits are mapped on SEG2 and SEG3 of all common terminals.
Table 39-7. Circular Shift Register Bit Mapping
Shift Register
Bit
COM
SEG
0
0
2
1
0
3
2
1
2
3
1
3
4
2
2
5
2
3
6
3
2
7
3
3
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