Datasheet

1056
42023E–SAM–07/2013
ATSAM4L8/L4/L2
39.7.2 Configuration Register
Name:
CFG
Access Type: Read/Write
Offset: 0x04
Reset Value: 0x00000000
NSU, DUTY, WMOD and XBIAS shall not be modified when LCDCA is enabled (SR.EN=1).
• NSU: Number of Segment Terminals in Use
This field indicates the number of segment terminals in use. It prevents any activity on muxes driving the unused segment
terminals.
• FCST: Fine Contrast
Defines the maximum voltage V
LCD
on segment and common terminals. FCST is a signed number (two's complement). New
value takes effect at the beginning of next frame.
V
LCD
= 3.0 V + (FCST[5:0] * 0.016 V)
• DUTY: Duty Select
This field defines the duty cycle.
• LOCK: Lock
0: Shadow display memory is unlocked.
1: Shadow display memory is locked and can’t be updated.
• BLANK: Blank LCD
0: LCD segments value is defined in shadow display memory.
1: Turns OFF all LCD segments.
• WMOD: Waveform Mode
0: low power waveform mode.
1: standard waveform mode.
31 30 29 28 27 26 25 24
-- NSU
23 22 21 20 19 18 17 16
-- FCST
15 14 13 12 11 10 9 8
------ DUTY
76543210
----LOCKBLANKWMODXBIAS
Table 39-13. Duty Selection
DUTY[1:0] Duty Bias COM pins Used
0 0 1/4 1/3 COM[0:3]
0 1 Static Static COM0
1 0 1/2 1/3 COM[0:1]
1 1 1/3 1/3 COM[0:2]