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MITSUBISHI MICROCOMPUTERS
M35060-XXXSP
SCREEN CHARACTER and PATTERN DISPLAY CONTROLLERS
PRECAUTIONS
1. Note for when starting of system
Before setting registers at the starting of system, be sure to re-
set the M35060-XXXSP by applying “L” level to the AC pin.
2. When power supply noise is generated, the internal oscillator
circuit does not stabilize, whereby causing horizontal jitters
across the picture display. Therefore, connect a bypass capaci-
tor between the power supply and GND.
3. Note for when throwing power supply into the M35060-XXXSP
When power to the M35060-XXXSP is activated, characters are
sometimes output without defining the internal display RAM,
composite RAM and register. Also, immediately after power is
turned ON, up until the oscillator circuit stabilizes, data is some-
times not set correctly in the register. Therefore, use the follow-
ing start-up procedure.
__
(a) Throwing power suppl__
=
“
L
”)
(b) Auto-clear releasing (AC pin = “H”)
(c) 200 ms waiting state (stabilization period of internal oscillation
circuit) Data input is forbidden.
(d) Set register LEV_____
(e) Set register PAL/NTSC
(f) Set register PCn
(g) 20 ms waiting state (stabilization period of internal oscillation
circuit)
Data input is forbidden.
(h) Set other registers
(i) Set SYRAM
(j) Set display RAM
(k) Set register DSPON and register DSPONV to display ON
4. Precautions when resuming internal oscillation from the OFF
state.
The internal oscillator circuit stops oscillating when register
LEVEL = 1, DSPON = 0, DSPONV = 0 and CS terminal = H.
When resuming internal oscillation from the OFF state, up until
the oscillator circuit stabilizes, data is sometimes not set cor-
rec__
(a) __
(b) CS pin = “L” (oscillation start)
(c) 20 ms waiting state (stabilization period of internal oscillation
circuit)
(d) Set register LEVEL 1 = 0
(e) Set other registers: SYRAM, display RAM
(f) Set register DSPON and register DSPONV to display ON
5. Note for oscillation
Make note of the fact that the internal oscillator circuit cannot
stabilize in the below situations.
(a)When the external composite video signal is discontinuous
(changing channels etc.)
(b) When change the setting of register PCn
(c) When change the setting of register LEVELn
When (a)~(c), set the display to OFF by registers DSPON and
DSPONV before change the setting. Other registers’ settings are
forbidden during 20ms after the setting.
6. When no external composite video signal is input (Without a sig-
nal, characters cannot be displayed by external synchronization.
Therefore, switch to internal synchronization.)
7. When signal level of the external composite video signal is ex-
tremely poor (With a weak electric field, character display is un-
controllable by external synchronization. Therefore, switch to
internal synchronization.)
8. When a crystal oscillator is connected to OSCIN (22-pin) or
OSCOUT (21-pin) (Talk with the manufacturer of the crystal os-
cillator you are using about matching it to this IC.)