M37221 Mitsubishi, M37221 Datasheet - Page 35

• Manufacturer Part Number: M37221
• Description: SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER for VOLTAGE SYNTHESIZER with ON-SCREEN DISPLAY CONTROLLER
• Manufacturer: Mitsubishi

Table 9. Outline of CRT display functions
CRT DISPLAY FUNCTIONS
(1) Outline of CRT Display Functions
Table 9 outlines the CRT display functions of the M37221EF-XXXSP.
The M37221EF-XXXSP incorporates a CRT display control circuit
of 24 characters
control register. Up to 256 kinds of characters can be displayed. The
colors can be specified for each character and up to 4 kinds of col-
ors can be displayed on one screen. A combination of up to 7 colors
can be obtained by using each output signal (R, G, and B).
Characters are displayed in a 12
smooth character patterns (refer to Figure 35).
The following shows the procedure how to display characters on the
CRT screen.
The CRT display circuit has an extended display mode. This mode
allows multiple lines (3 lines or more) to be displayed on the screen
by interrupting the display each time one line is displayed and rewrit-
ing data in the block for which display is terminated by software.
Figure 36 shows the structure of the CRT display control register.
Figure 37 shows the block diagram of the CRT display control circuit.
Number of display
characters
Dot structure
Kinds of characters
Kinds of character sizes
Color
Display expansion
Raster coloring
Character background
coloring
Write the display character code in the display RAM.
Specify the display color by using the color register.
Write the color register in which the display color is set in the dis-
play RAM.
Specify the vertical position by using the vertical position register.
Specify the character size by using the character size register.
Specify the horizontal position by using the horizontal position
register.
Write the display enable bit to the designated block display flag of
the CRT control register. When this is done, the CRT display starts
according to the input of the V
Parameter
Kinds of colors
Coloring unit
2 lines. CRT display is controlled by the CRT
24 characters
12
256 kinds
3 kinds
1 screen: 4 kinds, maximum 7 kinds
A character
Possible (multiline display)
Possible (maximum 7 kinds)
Possible (a character unit, 1 screen :
4 kinds, maximum 7 kinds)
SYNC
16 dots (refer to Figure 35)
16 dots configuration to obtain
signal.
Functions
2 lines
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER for VOLTAGE SYNTHESIZER
M37221EF-XXXSP,M37221EFSP
Fig. 35. CRT display character configuration
Fig. 36. Structure of CRT control register
7
Note: Display is controlled by logical product (AND)
between the all-blocks display control bit and
each block display control bit.
with ON-SCREEN DISPLAY CONTROLLER
MITSUBISHI MICROCOMPUTERS
12 dots
0
CRT control register
(CC: address 00EA
All-blocks display control bit (Note)
Block 1 display control
bit 0 : Block 1 display off
Block 2 display control
bit 0 : Block 2 display off
P1
0 : P1
1 : OUT2
0 : All-blocks display off
1 : All-blocks display on
1 : Block 1 display on
1 : Block 2 display on
0
/OUT2 pin switch bit
0
16
)
16 dots
35