m35061-xxxsp Renesas Electronics Corporation., m35061-xxxsp Datasheet - Page 28

• Manufacturer Part Number: m35061-xxxsp
• Description: Screen Character And Pattern Display Controllers
• Manufacturer: Renesas Electronics Corporation.

Notes on others
1. At system start-up
At system start-up, always set the AC pin to low level before setting
registers.
2. Power supply noise
When power supply noise is generated, the internal oscillator circuit
does not stabilize, whereby causing horizontal jitters across the pic-
ture display. Therefore, connect a bypass capacitor between the
power supply and GND.
3. At power on
When power to the M35061-XXXSP/FP is activated, characters are
sometimes output without defining the internal display RAM, com-
posite RAM and register. Also, immediately after power is turned on,
up until the oscillator circuit stabilizes, data is sometimes not set cor-
rectly in the register. Therefore, use the following start-up procedure.
4. When resuming internal oscillation from
The internal oscillator circuit stops oscillating when register LEVEL 1
= 1, DSPON = 0, DSPONV = 0 and CS pin = “H”.
When resuming internal oscillation from the off state, up until the os-
cillator circuit stabilizes, data is sometimes not set correctly in the
register. Therefore, start oscillation as follows.
5. Other notes on oscillation
Make note of the fact that the internal oscillator circuit cannot stabi-
lize in the below situations.
Before changing settings, turn registers DSPON and DSPONV off.
Also, disable data input for 20 m sec after making settings.
the off state
(a) Activate power. (AC pin = “L”)
(b) Engage auto clear. (AC pin = “H”)
(c) Disable data input for a 200 m sec (time enough to allow the
(d) Set register LEVEL n.
(e) Set register PAL/NTSC.
(f) Set register PC n.
(g) Disable data input for a 20 m sec (time enough to allow the
(h) Set other registers.
(i) Set the SYRAM.
(j) Set the internal display RAM.
(k) Turn registers DSPON and DSPONV on.
(a) CS pin = “H” (Oscillation off)
(b) CS pin =“L” (Oscillation start)
(c) Wait for a 20 m sec (time enough to allow the internal oscilla-
(d) Set register LEVEL 1 = 0.
(e) Set other registers, SYRAM and internal display RAM.
(f) Turn registers DSPON and DSPONV on.
(a) When the external composite video signal is discontinuous
(b) When register PC n setting is changed
(c) When register LEVEL n setting is changed
internal oscillator circuit to stabilize).
internal oscillator circuit to stabilize).
tor circuit to stabilize).
(when changing channels, etc.)
SCREEN CHARACTER and PATTERN DISPLAY CONTROLLERS
6. When no external composite video signal is in-
Without a signal, characters cannot be displayed by external syn-
chronization. Therefore, switch to internal synchronization.
7. When signal level of the external compos-
With a weak electric field, character display is uncontrollable by ex-
ternal synchronization. Therefore, switch to internal synchronization.
8. When a crystal oscillator is used as the IC's fsc
It is possible to connect a crystal oscillator between OSCIN and
OSCOUT to input the subcarrier frequency (fsc) signal to the OSCIN
pin. Talk with the manufacturer of the crystal oscillator you want to
use about matching it to this IC.
However, when using a crystal oscillator, it is not possible to super-
impose colors. Therefore, set the SCOR register (address 2B0
DAI register) to “0”.
Crystal oscillator frequency
put
ite video signal is extremely poor
input
M35061-XXXSP/FP
MITSUBISHI MICROCOMPUTERS
NTSC system : 3.580 MHz
PAL system
M-PAL system : 3.576 MHz
: 4.434 MHz
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in