CHAPTER 15 VFD CONTROLLER/DRIVER
310
User’s Manual U11302EJ4V0UM
15.3.2 One-display period and cut width
The digit signal is equally cut at the beginning and end of the display period by the cut width set by bits 1 to 3
(DIMS1 to DIMS3) of display mode register 1 (DSPM1).
Figure 15-6. Cut Width of Segment/Digit Signal
0 is output for the first one-display cycle when display is started from the display stop status.
Figure 15-7. VFD Controller Display Start Timing
n:
Displayed digits – 1 (Digits 2 to 16 can be selected using display mode register 1 (DSPM1))
T
DSP
: 1 display cycle (1024/f
x
(204.8
µ
s: @ 5.0 MHz operation) or 2048/f
x
(409.6
µ
s: @ 5.0 MHz operation))
T
KS
:
Key scan timing (T
KS
= T
DSP
)
T
DIG
: Pulse width of digit signal (Can be selected from 8 types using DSPM1)
Note
The user can select the cut width of the segment signals by setting bits 1 to 3 (DIMS1 to DIMS3) of DSPM1.
Therefore, actual output waveforms may be different from the above illustration and have the cut widths
shown in Figure 15-6.
1 display cycle = T
DSP
Segment signal
Digit signal
(1/16 of cut width)
Segment signal
Digit signal
(2/16 of cut width)
Segment signal
Digit signal
(4/16 of cut width)
1/16
1/16
1/8
1/8
1/4
1/4
Segment
signal
Note
Key scan flag
(KSF)
Can be changed
whenever necessary
FIPn
FIP2
FIP1
Digit signal
FIP0
T
DSP
T
KS
T
DIG
1 display
cycle
Key scan timing
Displaying
starts
Содержание mPD780204
Страница 2: ...2 User s Manual U11302EJ4V0UM MEMO ...