ETC HD66702RA02F

HD66702
(Dot Matrix Liquid Crystal Display Controller/Driver)
Description
The HD66702 dot-matrix liquid crystal display controller and driver LSI displays alphanumerics,
Japanese kana characters, and symbols. It can be configured to drive a dot-matrix liquid crystal display
under the control of a 4- or 8-bit microprocessor. Since all the functions required for driving a dot-matrix
liquid crystal display are internally provided on one chip, a minimal system can be interfaced with this
controller/driver.
A single HD66702 can display up to two 20-character lines.
The low 3-V power supply of the HD66702 under development is suitable for any portable battery-driven
product requiring low power dissipation.
Features
• 5 × 7 and 5 × 10 dot matrix possible
• 80 × 8-bit display RAM (80 characters max.)
• 7,200-bit character generator ROM
 160 character fonts (5 × 7 dot)
 32 character fonts (5 × 10 dot)
• 64 × 8-bit character generator RAM
 8 character fonts (5 × 7 dot)
 4 character fonts (5 × 10 dot)
• 16-common × 100-segment liquid crystal display driver
• Programmable duty cycles
 1/8 for one line of 5 × 7 dots with cursor
 1/11 for one line of 5 × 10 dots with cursor
 1/16 for two lines of 5 × 7 dots with cursor
227
HD66702
• Maximum display characters
 One line
1/8 duty cycle, 20-char. × 1-line
1/11 duty cycle, 20-char. × 1-line
 Two lines
1/16 duty cycle, 20-char. × 2-line
• Wide range of instruction functions
 Display clear, cursor home, display on/off, cursor on/off, display character blink, cursor shift,
display shift
• Choice of power supply (VCC): 4.5 to 5.5V (standard), 2.7 to 5.5V (low voltage)
• Automatic reset circuit that initializes the controller/driver after power on (standard version only)
• Independent LCD drive voltage driven off of the logic power supply (VCC): 3.0 to 8.3V
• Low power dissipation
• LQFP2020-144-pin, chip, chip wtith bump
Ordering Information
Type No.
Package
Operating Voltage
ROM Font
HCD66702RA00L
144-pin-chip
2.7 to 5.5V
Standard Japanese
HCD66702RA00BP
144-pin-chip with bump
2.7 to 5.5V
Standard Japanese
HCD66702RA01L
144-pin-chip
2.7 to 5.5V
Communication system
HCD66702RA02L
144-pin-chip
2.7 to 5.5V
European font
HD66702RA00F
FP-144A
4.5 to 5.5V
Standard Japanese
HD66702RA00FL
FP-144A
2.7 to 5.5V
Standard Japanese
HD66702RA01F
FP-144A
4.5 to 5.5V
Communication font
HD66702RA02F
FP-144A
4.5 to 5.5V
European font
228
HD66702
LCD-II Family Comparison
Item
LCD-II
(HD44780U)
Power supply voltage
HD66702
HD66710
HD66712U
2.7V to 5.5V
5 V ±10 %
(standard)
2.7 V to 5.5V
(low voltage)
2.7V to 5.5V
2.7V to 5.5V
Liquid crystal drive
voltage
3.0V to 11 V
3.0V to 8.3V
3.0V to 13.0V
2.7V to 11.0V
Maximum display digits
per chip
8 characters
× 2 lines
20 characters
× 2 lines
16 characters ×
2 lines/
8 characters ×
4 lines
24 characters ×
2 lines/
12 characters ×
4 lines
Segment display
None
None
40 segments
60 segments
Display duty cycle
1/8, 1/11, and 1/16 1/8, 1/11, and 1/16 1/17 and 1/33
1/17 and 1/33
CGROM
9,920 bits
(208 5 × 8 dot
characters and 32
5 × 10 dot
characters)
7,200 bits
(160 5 × 7 dot
characters and 32
5 × 10 dot
characters)
9,600 bits
(240 5 × 8 dot
characters)
9,600 bits
(240 5 × 8 dot
characters)
CGRAM
64 bytes
64 bytes
64 bytes
64 bytes
DDRAM
80 bytes
80 bytes
80 bytes
80 bytes
SEGRAM
None
None
8 bytes
16 bytes
Segment signals
40
100
40
60
Common signals
16
16
33
34
Liquid crystal drive
waveform
A
B
B
B
Bleeder resistor for LCD
power supply
External
(adjustable)
External
(adjustable)
External
(adjustable)
External
(adjustable)
Clock source
External resistor or External resistor or External resistor
external clock
external clock
or external clock
External resistor or
external clock
Rf oscillation frequency
(frame frequency)
270 kHz ±30%
(59 to 110 Hz for
1/8 and 1/16 duty
cycle; 43 to 80 Hz
for 1/11 duty cycle)
320 kHz ±30%
(70 to 130 Hz for
1/8 and 1/16 duty
cycle; 51 to 95 Hz
for 1/11 duty cycle)
270 kHz ±30%
(56 to 103 Hz for
1/17 duty cycle;
57 to 106 Hz for
1/33 duty cycle)
270 kHz ±30%
(56 to 103 Hz for
1/17 duty cycle;
57 to 106 Hz for
1/33 duty cycle)
Rf resistance
91 kΩ: 5-V
operation;
75 kΩ: 3-V
operation
68 kΩ: 5-V
operation;
56 kΩ: (3-V
operation)
91 kΩ: 5-V
operation;
75 kΩ: 3-V
operation
130 kΩ: 5-V
operation
110 kΩ: 3-V
operation
229
HD66702
LCD-II
(HD44780)
HD66702
HD66710
Liquid crystal voltage
booster circuit
None
None
2-3 times step-up 2-3 times step-up
circuit
circuit
Extension driver control
signal
Independent
control signal
Independent
control signal
Used in common
with a driver
output pin
Reset function
Power on automatic Power on automatic Power on
reset
reset
automatic reset
Power on
automatic reset or
Reset input
Instructions
LCD-II
(HD44780)
Fully compatible
with the LCD-II
Uppercompatible
with the LCD-II
Upper compatible
with the LCD-II
Number of displayed
lines
1 or 2
1 or 2
1, 2, or 4
1, 2, or 4
Low power mode
None
None
Available
Available
Horizontal scroll
Character unit
Character unit
Dot unit
Dot unit
Bus interface
4 bits/8 bits
4 bits/8 bits
4 bits/8 bits
Serial;
4 bits/8 bits
CPU bus timing
2 MHz: 5-V
operation;
1 MHz: 3-V
operation
1 MHz
2 MHz: 5-V
operation;
1 MHz: 3-V
operation
2 MHz: 5-V
operation;
1 MHz: 3-V
operation
Package
QFP-1420-80
80-pin bare chip
LQFP-2020-144
144-pin bare chip
QFP-1420-100
TCP-128
TQFP-1414-100 128-pin bare chip
100-pin bare chip
Item
230
HD66712U
Independent
control signal
HD66702
HD66702 Block Diagram
OSC1 OSC2 EXT
M
Reset
circuit
ACL
Timing
generator
CPG
8
RS
R/W
E
Instruction
register (IR)
7
Input/
output
buffer
8
16-bit
shift
register
Common
signal
driver
100-bit
latch
circuit
Segment
signal
driver
7
100-bit
shift
register
8
7
DB4 to
DB7
D
Display
data RAM
(DDRAM)
80 × 8 bits
Instruction
decoder
MPU
interface
Address
counter
DB0 to
DB3
CL1
CL2
Data
register
(DR)
SEG1 to
SEG100
100
8
8
GND
16
7
8
LCD drive
voltage
selector
Busy
flag
TEST
COM1 to
COM16
Character
generator
ROM
(CGROM)
7,200 bits
Character
generator
RAM
(CGRAM)
64 bytes
5
Cursor
and
blink
controller
5
Parallel/serial converter
and
attribute circuit
VCC
V1
V2
V3
V4
V5
231
HD66702
144
143
142
141
140
139
138
137
136
135
134
133
132
131
130
129
128
127
126
125
124
123
122
121
120
119
118
117
116
115
114
113
112
111
110
109
SEG35
SEG36
SEG37
SEG38
SEG39
SEG40
SEG41
SEG42
SEG43
SEG44
SEG45
SEG46
SEG47
SEG48
SEG49
SEG50
SEG51
SEG52
SEG53
SEG54
SEG55
SEG56
SEG57
SEG58
SEG59
SEG60
SEG61
SEG62
SEG63
SEG64
SEG65
SEG66
SEG67
SEG68
SEG69
SEG70
HD66702 Pad Arrangement
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
(Top view)
Type code
HD66702
OSC1
VCC
VCC
V1
V2
V3
V4
V5
CL1
CL2
M
D
EXT
TEST*
GND
RS
R/W
E
DB0
DB1
DB2
DB3
DB4
DB5
DB6
DB7
COM1
COM2
COM3
COM4
COM5
COM6
COM7
COM8
COM9
COM10
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
SEG34
SEG33
SEG32
SEG31
SEG30
SEG29
SEG28
SEG27
SEG26
SEG25
SEG24
SEG23
SEG22
SEG21
SEG20
SEG19
SEG18
SEG17
SEG16
SEG15
SEG14
SEG13
SEG12
SEG11
SEG10
SEG9
SEG8
SEG7
SEG6
SEG5
SEG4
SEG3
SEG2
SEG1
GND
OSC2
Note: * :
:
:
:
:
:
232
Test pins to be grounded
Power supply pins
Power supply pins (ground)
Input pins
Output pins
Input/Output pins
Chip size = 5.20 × 5.20 mm
Minimum pad pitch = 130 µm
Pad size = 90 × 90 µm
108
107
106
105
104
103
102
101
100
99
98
97
96
95
94
93
92
91
90
89
88
87
86
85
84
83
82
81
80
79
78
77
76
75
74
73
SEG71
SEG72
SEG73
SEG74
SEG75
SEG76
SEG77
SEG78
SEG79
SEG80
SEG81
SEG82
SEG83
SEG84
SEG85
SEG86
SEG87
SEG88
SEG89
SEG90
SEG91
SEG92
SEG93
SEG94
SEG95
SEG96
SEG97
SEG98
SEG99
SEG100
COM16
COM15
COM14
COM13
COM12
COM11
HD66702
HCD66702 Pad Location Coordinates
Pad
No.
Pad
Name
X (µm)
Y (µm)
Pad
No.
Pad
Name
1
SEG34
–2475
X (µm)
Y (µm)
2350
31
SEG4
–2475
–1600
2
SEG33
–2475
2205
32
SEG3
–2475
–1735
3
SEG32
–2475
2065
33
SEG2
–2475
–1870
4
SEG31
–2475
1925
34
SEG1
–2475
–2010
5
SEG30
–2475
1790
35
GND
–2475
–2180
6
SEG29
–2475
1655
36
OSC2
–2475
–2325
7
SEG28
–2475
1525
37
OSC1
–2445
–2475
8
SEG27
–2475
1395
38
VCC
–2305
–2475
9
SEG26
–2475
1265
39
VCC
–2165
–2475
10
SEG25
–2475
1135
40
V1
–2025
–2475
11
SEG24
–2475
1005
41
V2
–1875
–2475
12
SEG23
–2475
875
42
V3
–1745
–2475
13
SEG22
–2475
745
43
V4
–1595
–2475
14
SEG21
–2475
615
44
V5
–1465
–2475
15
SEG20
–2475
485
45
CL1
–1335
–2475
16
SEG19
–2475
355
46
CL2
–1185
–2475
17
SEG18
–2475
225
47
M
–1055
–2475
18
SEG17
–2475
95
48
D
–905
–2475
19
SEG16
–2475
–35
49
EXT
–775
–2475
20
SEG15
–2475
–165
50
TEST
–625
–2475
21
SEG14
–2475
–295
51
GND
–495
–2475
22
SEG13
–2475
–425
52
RS
–345
–2475
23
SEG12
–2475
–555
53
R/:
–195
–2475
24
SEG11
–2475
–685
54
E
–45
–2475
25
SEG10
–2475
–815
55
DB0
85
–2475
26
SEG9
–2475
–945
56
DB1
235
–2475
27
SEG8
–2475
–1075
57
DB2
365
–2475
28
SEG7
–2475
–1205
58
DB3
515
–2475
29
SEG6
–2475
–1335
59
DB4
645
–2475
30
SEG5
–2475
–1465
60
DB5
795
–2475
233
HD66702
Pad
No.
Pad
Name
X (µm)
Y (µm)
Pad
No.
Pad
Name
X (µm)
61
DB6
925
–2475
91
SEG88
2475
95
62
DB7
1075
–2475
92
SEG87
2475
225
63
COM1
1205
–2475
93
SEG86
2475
355
64
COM2
1335
–2475
94
SEG85
2475
485
65
COM3
1465
–2475
95
SEG84
2475
615
66
COM4
1595
–2475
96
SEG83
2475
745
67
COM5
1725
–2475
97
SEG82
2475
875
68
COM6
1855
–2475
98
SEG81
2475
1005
69
COM7
1990
–2475
99
SEG80
2475
1135
70
COM8
2125
–2475
100
SEG79
2475
1265
71
COM9
2265
–2475
101
SEG78
2475
1395
72
COM10
2410
–2475
102
SEG77
2475
1525
73
COM11
2475
–2290
103
SEG76
2475
1655
74
COM12
2475
–2145
104
SEG75
2475
1790
75
COM13
2475
–2005
105
SEG74
2475
1925
76
COM14
2475
–1865
106
SEG73
2475
2065
77
COM15
2475
–1730
107
SEG72
2475
2205
78
COM16
2475
–1595
108
SEG71
2475
2350
79
SEG100
2475
–1465
109
SEG70
2320
2475
80
SEG99
2475
–1335
110
SEG69
2175
2475
81
SEG98
2475
–1205
111
SEG68
2035
2475
82
SEG97
2475
–1075
112
SEG67
1895
2475
83
SEG96
2475
–945
113
SEG66
1760
2475
84
SEG95
2475
–815
114
SEG65
1625
2475
85
SEG94
2475
–685
115
SEG64
1495
2475
86
SEG93
2475
–555
116
SEG63
1365
2475
87
SEG92
2475
–425
117
SEG62
1235
2475
88
SEG91
2475
–295
118
SEG61
1105
2475
89
SEG90
2475
–165
119
SEG60
975
2475
90
SEG89
2475
–35
120
SEG59
845
2475
234
Y (µm)
HD66702
Pad
No.
Pad
Name
X (µm)
Y (µm)
Pad
No.
Pad
Name
X (µm)
121
SEG58
715
2475
133
SEG46
–845
2475
122
SEG57
585
2475
134
SEG45
–975
2475
123
SEG56
455
2475
135
SEG44
–1105
2475
124
SEG55
325
2475
136
SEG43
–1235
2475
125
SEG54
195
2475
137
SEG42
–1365
2475
126
SEG53
65
2475
138
SEG41
–1495
2475
127
SEG52
–65
2475
139
SEG40
–1625
2475
128
SEG51
–195
2475
140
SEG39
–1760
2475
129
SEG50
–325
2475
141
SEG38
–1895
2475
130
SEG49
–455
2475
142
SEG37
–2035
2475
131
SEG48
–585
2475
143
SEG36
–2175
2475
132
SEG47
–715
2475
144
SEG35
–2320
2475
Y (µm)
Notes: 1. Coordinates originate from the chip center.
2. The above are preliminary specifications, and may be subject to change.
235
HD66702
144
143
142
141
140
139
138
137
136
135
134
133
132
131
130
129
128
127
126
125
124
123
122
121
120
119
118
117
116
115
114
113
112
111
110
109
SEG35
SEG36
SEG37
SEG38
SEG39
SEG40
SEG41
SEG42
SEG43
SEG44
SEG45
SEG46
SEG47
SEG48
SEG49
SEG50
SEG51
SEG52
SEG53
SEG54
SEG55
SEG56
SEG57
SEG58
SEG59
SEG60
SEG61
SEG62
SEG63
SEG64
SEG65
SEG66
SEG67
SEG68
SEG69
SEG70
HD66702 Pin Arrangement
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
FP-144A
(Top view)
OSC1
VCC
VCC
V1
V2
V3
V4
V5
CL1
CL2
M
D
EXT
TEST *
GND
RS
R/W
E
DB0
DB1
DB2
DB3
DB4
DB5
DB6
DB7
COM1
COM2
COM3
COM4
COM5
COM6
COM7
COM8
COM9
COM10
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
SEG34
SEG33
SEG32
SEG31
SEG30
SEG29
SEG28
SEG27
SEG26
SEG25
SEG24
SEG23
SEG22
SEG21
SEG20
SEG19
SEG18
SEG17
SEG16
SEG15
SEG14
SEG13
SEG12
SEG11
SEG10
SEG9
SEG8
SEG7
SEG6
SEG5
SEG4
SEG3
SEG2
SEG1
GND
OSC2
Note: * :
:
:
:
:
:
236
Test pins to be grounded
Power supply pins
Power supply pins (ground)
Input pins
Output pins
Input/Output pins
108
107
106
105
104
103
102
101
100
99
98
97
96
95
94
93
92
91
90
89
88
87
86
85
84
83
82
81
80
79
78
77
76
75
74
73
SEG71
SEG72
SEG73
SEG74
SEG75
SEG76
SEG77
SEG78
SEG79
SEG80
SEG81
SEG82
SEG83
SEG84
SEG85
SEG86
SEG87
SEG88
SEG89
SEG90
SEG91
SEG92
SEG93
SEG94
SEG95
SEG96
SEG97
SEG98
SEG99
SEG100
COM16
COM15
COM14
COM13
COM12
COM11
HD66702
Pin Functions
Table 1
Pin Functional Description
Signal
I/O
Device
Interfaced with
RS
I
MPU
Selects registers
0: Instruction register (for write)
Busy flag: address counter (for read)
1: Data register (for write and read)
R/:
I
MPU
Selects read or write
0: Write
1: Read
E
I
MPU
Starts data read/write
DB4 to DB7
I/O
MPU
Four high order bidirectional tristate data bus pins.
Used for data transfer between the MPU and the
HD66702. DB7 can be used as a busy flag.
DB0 to DB3
I/O
MPU
Four low order bidirectional tristate data bus pins. Used
for data transfer between the MPU and the HD66702.
These pins are not used during 4-bit operation.
Function
CL1
O
Extension driver
Clock to latch serial data D sent to the extension driver
CL2
O
Extension driver
Clock to shift serial data D
M
O
Extension driver
Switch signal for converting the liquid crystal drive
waveform to AC
D
O
Extension driver
Character pattern data corresponding to each segment
signal
COM1 to COM16
O
LCD
Common signals that are not used are changed to nonselection waveforms. COM9 to COM16 are nonselection waveforms at 1/8 duty factor and COM12 to
COM16 are non-selection waveforms at 1/11 duty
factor.
SEG1 to SEG100
O
LCD
Segment signals
V1 to V5
—
Power supply
Power supply for LCD drive
VCC, GND
—
Power supply
VCC: +5V or +3V, GND: 0V
TEST
I
—
Test pin, which must be grounded
EXT
I
—
0: Enables extension driver control signals CL1, CL2,
M, and D to be output from its corresponding pins.
1: Drives CL1, CL2, M, and D as tristate, lowering
power dissipation.
OSC1, OSC2
—
—
Pins for connecting the registers of the internal clock
oscillation. When the pin input is an external clock, it
must be input to OSC1.
237
HD66702
Function Description
Registers
The HD66702 has two 8-bit registers, an instruction register (IR) and a data register (DR).
The IR stores instruction codes, such as display clear and cursor shift, and address information for display
data RAM (DDRAM) and character generator RAM (CGRAM). The IR can only be written from the
MPU.
The DR temporarily stores data to be written into DDRAM or CGRAM. Data written into the DR from
the MPU is automatically written into DDRAM or CGRAM by an internal operation. The DR is also used
for data storage when reading data from DDRAM or CGRAM. When address information is written into
the IR, data is read and then stored into the DR from DDRAM or CGRAM by an internal operation. Data
transfer between the MPU is then completed when the MPU reads the DR. After the read, data in
DDRAM or CGRAM at the next address is sent to the DR for the next read from the MPU. By the
register selector (RS) signal, these two registers can be selected (Table 2).
Busy Flag (BF)
When the busy flag is 1, the HD66702 is in the internal operation mode, and the next instruction will not
be accepted. When RS = 0 and R/W = 1 (Table 2), the busy flag is output to DB7. The next instruction
must be written after ensuring that the busy flag is 0.
Address Counter (AC)
The address counter (AC) assigns addresses to both DDRAM and CGRAM. When an address of an
instruction is written into the IR, the address information is sent from the IR to the AC. Selection of
either DDRAM or CGRAM is also determined concurrently by the instruction.
After writing into (reading from) DDRAM or CGRAM, the AC is automatically incremented by 1
(decremented by 1). The AC contents are then output to DB0 to DB6 when RS = 0 and R/ = 1 (Table
2).
:
Table 2
Register Selection
:
RS
R/
0
0
IR write as an internal operation (display clear, etc.)
0
1
Read busy flag (DB7) and address counter (DB0 to DB6)
1
0
DR write as an internal operation (DR to DDRAM or CGRAM)
1
1
DR read as an internal operation (DDRAM or CGRAM to DR)
238
Operation
HD66702
Display Data RAM (DDRAM)
Display data RAM (DDRAM) stores display data represented in 8-bit character codes. Its extended
capacity is 80 × 8 bits, or 80 characters. The area in display data RAM (DDRAM) that is not used for
display can be used as general data RAM. See Figure 1 for the relationships between DDRAM addresses
and positions on the liquid crystal display.
The DDRAM address (ADD) is set in the address counter (AC) as hexadecimal.
• 1-line display (N = 0) (Figure 2)
 When there are fewer than 80 display characters, the display begins at the head position. For
example, if using only the HD66702, 20 characters are displayed. See Figure 3.
When the display shift operation is performed, the DDRAM address shifts. See Figure 3.
High order
bits
Low order
bits
Example: DDRAM address 4E
AC
(hexadecimal) AC6 AC5 AC4 AC3 AC2 AC1 AC0
1
0
0
1
1
1
0
19
20
Figure 1 DDRAM Address
Display position
(digit)
1
2
3
DDRAM
00 01
address
(hexadecimal)
4
02
5
03 04
79
..................
80
4E 4F
Figure 2 1-Line Display
Display
position
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
DDRAM
address
00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12 13
For
shift left
01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12 13 14
For
shift right 4F 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12
Figure 3 1-Line by 20-Character Display Example
239
HD66702
• 2-line display (N = 1) (Figure 4)
 Case 1: When the number of display characters is less than 40 × 2 lines, the two lines are
displayed from the head. Note that the first line end address and the second line start address are
not consecutive. For example, when just the HD66702 is used, 20 characters × 2 lines are
displayed. See Figure 5.
When display shift operation is performed, the DDRAM address shifts. See Figure 5.
Display
position
1
2
3
00 01
DDRAM
address
(hexadecimal) 40 41
4
5
39
40
02
03 04
..................
26 27
42
43 44
..................
66 67
Figure 4 2-Line Display
Display
position
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
DDRAM
address
00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12 13
For
shift left
01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12 13 14
40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F 50 51 52 53
41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F 50 51 52 53 54
27 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12
For
shift right
67 40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F 50 51 52
Figure 5 2-Line by 20-Character Display Example
240
HD66702
 Case 2: For a 28-character × 2-line display, the HD66702 can be extended using one 40-output
extension driver. See Figure 6.
When display shift operation is performed, the DDRAM address shifts. See Figure 6.
Display
position
DDRAM
address
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12 13 14 15 16 17 18 19 1A 1B
40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F 50 51 52 53 54 55 56 57 58 59 5A 5B
HD66702 display
For
shift left
Extension driver
display
01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12 13 14 15 16 17 18 19 1A 1B 1C
41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F 50 51 52 53 54 55 56 57 58 59 5A 5B 5C
27 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12 13 14 15 16 17 18 19 1A
For
shift right
67 40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F 50 51 52 53 54 55 56 57 58 59 5A
Figure 6 2-Line by 28-Character Display Example
241
HD66702
Character Generator ROM (CGROM)
The character generator ROM generates 5 × 7 dot or 5 × 10 dot character patterns from 8-bit character
codes (Table 5). It can generate 160 5 × 7 dot character patterns and 32 5 × 10 dot character patterns.
User-defined character patterns are also available by mask-programmed ROM.
Character Generator RAM (CGRAM)
In the character generator RAM, the user can rewrite character patterns by program. For 5 × 7 dots, eight
character patterns can be written, and for 5 × 10 dots, four character patterns can be written.
Write the character codes at the addresses shown as the left column of Table 5 to show the character
patterns stored in CGRAM.
See Table 6 for the relationship between CGRAM addresses and data and display patterns.
Areas that are not used for display can be used as general data RAM.
Modifying Character Patterns
• Character pattern development procedure
The following operations correspond to the numbers listed in Figure 7:
1. Determine the correspondence between character codes and character patterns.
2. Create a listing indicating the correspondence between EPROM addresses and data.
3. Program the character patterns into the EPROM.
4. Send the EPROM to Hitachi.
5. Computer processing on the EPROM is performed at Hitachi to create a character pattern listing,
which is sent to the user.
6. If there are no problems within the character pattern listing, a trial LSI is created at Hitachi and
samples are sent to the user for evaluation. When it is confirmed by the user that the character
patterns are correctly written, mass production of the LSI proceeds at Hitachi.
242
HD66702
Hitachi
User
Start
Computer
processing
Create character
pattern listing
5
Evaluate
character
patterns
No
Determine
character patterns
1
Create EPROM
address data listing
2
Write EPROM
3
EPROM → Hitachi
4
OK?
Yes
Art work
M/T
Masking
Trial
Sample
Sample
evaluation
OK?
6
No
Yes
Mass
production
Note: For a description of the numbers used in this figure, refer to the preceding page.
Figure 7 Character Pattern Development Procedure
243
HD66702
• Programming character patterns
This section explains the correspondence between addresses and data used to program character
patterns in EPROM. The HD66702 character generator ROM can generate 160 5 × 7 dot character
patterns and 32 5 × 10 dot character patterns for a total of 192 different character patterns.
 5 × 7 dot character pattern
EPROM address data and character pattern data correspond with each other to form a 5 × 7 dot
character pattern (Table 3).
Table 3
Example of Correspondence between EPROM Address Data and Character Pattern
(5 × 7 dots)
EPROM Address
Data
A 1 0 A9 A8 A7 A6 A5 A4 A3 A2 A1 A0
0
1
0
1
0
0
Character code
Notes: 1.
2.
3.
4.
5.
6.
244
1
0
LSB
O 4 O3 O2 O1 O0
0 0 0
1
1
1
1
0
0
0
1
1
0
0
0
1
0
1
0
1
0
0
0
1
0
1
1
1
1
1
1
0
1
0
0
1
0
1
0
0
1
0
1
1
0
0
1
0
1
1
0
1
0
0
0
1
1
1
1
0
0
0
0
0
Line
position
Fill line 8 (cursor position)
with 0s
EPROM addresses A10 to A3 correspond to a character code.
EPROM addresses A2 to A0 specify a line position of the character pattern.
EPROM data O4 to O0 correspond to character pattern data.
A lit display position (black) corresponds to a 1.
Line 8 (cursor position) of the character pattern must be blanked with 0s.
EPROM data O5 to O7 are not used.
HD66702

5 × 10 dot character pattern
EPROM address data and character pattern data correspond with each other to form a 5 × 10 dot
character pattern (Table 4).
 Handling unused character patterns
1. EPROM data outside the character pattern area: Ignored by the character generator ROM
for display operation so 0 or 1 is arbitrary.
2. EPROM data in CGRAM area: Ignored by the character generator ROM for display
operation so 0 or 1 is arbitrary.
3. EPROM data used when the user does not use any HD66702 character pattern: According
to the user application, handled in one of the two ways listed as follows.
a. When unused character patterns are not programmed: If an unused character code is
written into DDRAM, all its dots are lit. By not programing a character pattern, all of its bits
become lit. (This is due to the EPROM being filled with 1s after it is erased.)
b. When unused character patterns are programmed as 0s: Nothing is displayed even if
unused character codes are written into DDRAM. (This is equivalent to a space.)
Table 4
Example of Correspondence between EPROM Address Data and Character Pattern
(5 × 10 dots)
EPROM Address
Data
A 1 0 A9 A8 A7 A6 A5 A4 A3 A2 A1 A0
LSB
O 4 O3 O2 O1 O0
1
1
1
1
0
0
0
1
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
1
0
0
1
1
0
1
0
1
1
1
0
0
1
1
1
0
0
1
0
0
0
1
1
0
1
1
0
0
0
1
1
1
0
0
1
1
1
1
1
1
1
0
0
0
0
1
1
0
0
1
0
0
0
1
0
0
0
0
0
0
0
1
1
0
0
1
0
0
0
1
0
0
1
0
0
0
0
1
1
0
0
1
0
0
0
1
0
1
0
0
0
0
0
0
Character code
Line
position
Fill line 11 (cursor position)
with 0s
Notes: 1. EPROM addresses A10 to A3 correspond to a character code. Set A8 and A9 of character
pattern lines 9, 10, and 11 to 0s.
2. EPROM addresses A2 to A0 specify a line position of the character pattern.
3. EPROM data O4 to O0 correspond to character pattern data.
4. A lit display position (black) corresponds to a 1.
5. Blank out line 11 (cursor position) of the character pattern with 0s.
6. EPROM data O5 to O7 are not used.
245
HD66702
Table 5
Correspondence between Character Codes and Character Patterns (ROM code: A00)
Lower
4 Bits
Upper 4
Bits
0000 0010 0011 0100 0101 0110 0111 1010 1011 1100 1101 1110 1111
xxxx0000
CG
RAM
(1)
xxxx0001
(2)
xxxx0010
(3)
xxxx0011
(4)
xxxx0100
(5)
xxxx0101
(6)
xxxx0110
(7)
xxxx0111
(8)
xxxx1000
(1)
xxxx1001
(2)
xxxx1010
(3)
xxxx1011
(4)
xxxx1100
(5)
xxxx1101
(6)
xxxx1110
(7)
xxxx1111
(8)
Note: The user can specify any pattern for character-generator RAM.
246
HD66702
Table 5
Correspondence between Character Codes and Character Patterns (ROM code: A01)
Lower
4 Bits
Upper 4
Bits
0000 0010 0011 0100 0101 0110 0111 1010 1011 1100 1101 1110 1111
xxxx0000
CG
RAM
(1)
xxxx0001
(2)
xxxx0010
(3)
xxxx0011
(4)
xxxx0100
(5)
xxxx0101
(6)
xxxx0110
(7)
xxxx0111
(8)
xxxx1000
(1)
xxxx1001
(2)
xxxx1010
(3)
xxxx1011
(4)
xxxx1100
(5)
xxxx1101
(6)
xxxx1110
(7)
xxxx1111
(8)
247
HD66702
Table 5
Correspondence between Character Codes and Character Patterns (ROM code: A02)
Lower
4 Bits
248
Upper 4
Bits
0000 0010 0011 0100 0101 0110 0111 1010 1011 1100 1101 1110 1111
xxxx0000
CG
RAM
(1)
xxxx0001
(2)
xxxx0010
(3)
xxxx0011
(4)
xxxx0100
(5)
xxxx0101
(6)
xxxx0110
(7)
xxxx0111
(8)
xxxx1000
(1)
xxxx1001
(2)
xxxx1010
(3)
xxxx1011
(4)
xxxx1100
(5)
xxxx1101
(6)
xxxx1110
(7)
xxxx1111
(8)
HD66702
Table 6
Relationship between CGRAM Addresses, Character Codes (DDRAM) and Character
Patterns (CGRAM Data)
For 5 × 7 dot character patterns
Character Codes
(DDRAM data)
CGRAM Address
Character Patterns
(CGRAM data)
7 6 5 4 3 2 1 0
5 4 3 2 1 0
7 6 5 4 3 2 1 0
High
High
Low
0 0 0 0 * 0 0 0
0 0 0 0 * 0 0 1
0 0 0 0 * 1 1 1
0 0 0
0 0 1
1 1 1
Low
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
1
1
1
1
0
0
1
1
0
1
0
1
High
* * *
* * *
* * *
* * *
* * *
Low
1
1
1
1
1
1
1
0
1
0
1
0
1
0
0
0
1
0
0
1
0
0
0
0
0
1
1
0
1
0
0
0
1
0
0
1
1
0
0
0
0
0
1
1
1
1
1
0
1
0
0
1
0
1
0
0
0
1
1
0
1
0
0
0
0
1
1
0
0
0
1
0
1
0
1
0
1
0
0
0
Character
pattern
Cursor position
* * *
Notes: 1. Character code bits 0 to 2 correspond to CGRAM address bits 3 to 5 (3 bits: 8 types).
2. CGRAM address bits 0 to 2 designate the character pattern line position. The 8th line is the
cursor position and its display is formed by a logical OR with the cursor.
Maintain the 8th line data, corresponding to the cursor display position, at 0 as the cursor
display.
If the 8th line data is 1, 1 bits will light up the 8th line regardless of the cursor presence.
3. Character pattern row positions correspond to CGRAM data bits 0 to 4 (bit 4 being at the left ).
Since CGRAM data bits 5 to 7 are not used for display, they can be used for general data
RAM.
4. As shown Tables 5 and 6, CGRAM character patterns are selected when character code bits 4
to 7 are all 0. However, since character code bit 3 has no effect, the R display example above
can be selected by either character code 00H or 08H.
5. 1 for CGRAM data corresponds to display selection and 0 to non-selection.
* Indicates no effect.
249
HD66702
Table 6
Relationship between CGRAM Addresses, Character Codes (DDRAM) and Character
Patterns (CGRAM Data) (cont)
For 5 × 10 dot character patterns
Character Codes
(DDRAM data)
CGRAM Address
Character Patterns
(CGRAM data)
7 6 5 4 3 2 1 0
5 4 3 2 1 0
7 6 5 4 3 2 1 0
High
High
Low
0 0 0 0 * 0 0 *
0 0 0 0 * 1 1 *
0 0
1 1
Low
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
1
1
1
1
1
1
1
0
0
0
1
1
1
1
0
1
1
0
0
1
1
1
0
1
0
1
0
1
High
* * *
* * *
* * *
* * *
* * *
Low
0
0
1
1
1
1
1
1
1
1
0
*
0
0
0
1
0
0
1
0
0
0
0
*
0
0
1
0
0
0
1
0
0
0
0
*
0
0
1
0
0
0
1
0
0
0
0
*
0
0
0
1
1
1
0
0
0
0
0
*
Character
pattern
Cursor position
* * * * *
* * *
* * *
* * * * *
* * *
* * * * *
Notes: 1. Character code bits 1 and 2 correspond to CGRAM address bits 4 and 5 (2 bits: 4 types).
2. CGRAM address bits 0 to 3 designate the character pattern line position. The 11th line is the
cursor position and its display is formed by a logical OR with the cursor.
Maintain the 11th line data corresponding to the cursor display positon at 0 as the cursor
display.
If the 11th line data is 1, 1 bits will light up the 11th line regardless of the cursor presence.
Since lines 12 to 16 are not used for display, they can be used for general data RAM.
3. Character pattern row positions are the same as 5 × 7 dot character pattern positions.
4. CGRAM character patterns are selected when character code bits 4 to 7 are all 0.
However, since character code bits 0 and 3 have no effect, the P display example above can
be selected by character codes 00H, 01H, 08H, and 09H.
5. 1 for CGRAM data corresponds to display selection and 0 to non-selection.
* Indicates no effect.
250
HD66702
Timing Generation Circuit
The timing generation circuit generates timing signals for the operation of internal circuits such as
DDRAM, CGROM and CGRAM. RAM read timing for display and internal operation timing by MPU
access are generated separately to avoid interfering with each other. Therefore, when writing data to
DDRAM, for example, there will be no undesirable interferences, such as flickering, in areas other than
the display area.
Liquid Crystal Display Driver Circuit
The liquid crystal display driver circuit consists of 16 common signal drivers and 100 segment signal
drivers. When the character font and number of lines are selected by a program, the required common
signal drivers automatically output drive waveforms, while the other common signal drivers continue to
output non-selection waveforms.
Sending serial data always starts at the display data character pattern corresponding to the last address of
the display data RAM (DDRAM).
Since serial data is latched when the display data character pattern corresponding to the starting address
enters the internal shift register, the HD66702 drives from the head display.
Cursor/Blink Control Circuit
The cursor/blink control circuit generates the cursor or character blinking. The cursor or the blinking will
appear with the digit located at the display data RAM (DDRAM) address set in the address counter (AC).
For example (Figure 8), when the address counter is 08H, the cursor position is displayed at DDRAM
address 08H.
AC6 AC5 AC4 AC3 AC2 AC1 AC0
AC
0
0
0
1
0
0
0
For a 1-line display
Display position
1
2
3
4
5
6
7
8
9
10
11
DDRAM address
(hexadecimal)
00
01
02
03
04
05
06
07
08
09
0A
cursor position
For a 2-line display
Display position
DDRAM address
(hexadecimal)
1
2
3
4
5
6
7
8
9
10
11
00
01
02
03
04
05
06
07
08
09
0A
40
41
42
43
44
45
46
47
48
49
4A
cursor position
Note: The cursor or blinking appears when the address counter (AC) selects the character
generator RAM (CGRAM). However, the cursor and blinking become meaningless.
The cursor or blinking is displayed in the meaningless position when the AC is a CGRAM address.
Figure 8 Cursor/Blink Display Example
251
HD66702
Interfacing to the MPU
The HD66702 can send data in either two 4-bit operations or one 8-bit operation, thus allowing
interfacing with 4- or 8-bit MPUs.
• For 4-bit interface data, only four bus lines (DB4 to DB7) are used for transfer. Bus lines DB0 to DB3
are disabled. The data transfer between the HD66702 and the MPU is completed after the 4-bit data
has been transferred twice. As for the order of data transfer, the four high order bits (for 8-bit
operation, DB4 to DB7) are transferred before the four low order bits (for 8-bit operation, DB0 to
DB3).
The busy flag must be checked (one instruction) after the 4-bit data has been transferred twice. Two
more 4-bit operations then transfer the busy flag and address counter data.
• For 8-bit interface data, all eight bus lines (DB0 to DB7) are used.
RS
R/W
E
DB7
IR7
IR3
BF
AC3
DR7
DR3
DB6
IR6
IR2
AC6
AC2
DR6
DR2
DB5
IR5
IR1
AC5
AC1
DR5
DR1
DB4
IR4
IR0
AC4
AC0
DR4
DR0
Instruction register (IR)
write
Busy flag (BF) and
address counter (AC)
read
Data register (DR)
read
Figure 9 4-Bit Transfer Example
252
HD66702
Reset Function
Initializing by Internal Reset Circuit
An internal reset circuit automatically initializes the HD66702 when the power is turned on. The
following instructions are executed during the initialization. The busy flag (BF) is kept in the busy state
until the initialization ends (BF = 1). The busy state lasts for 15 ms after VCC rises to 4.5V, or 40 ms after
VCC rises to 2.7V.
1. Display clear
2. Function set:
DL = 1; 8-bit interface data
N = 0; 1-line display
F = 0; 5 × 7 dot character font
3. Display on/off control:
D = 0; Display off
C = 0; Cursor off
B = 0; Blinking off
4. Entry mode set:
I/D = 1; Increment by 1
S = 0; No shift
Note: If the electrical characteristics conditions listed under the Table Power Supply Conditions Using
Internal Reset Circuit are not met, the internal reset circuit will not operate normally and will fail
to initialize the HD66702. For such a case, initial-ization must be performed by the MPU as
explained in the section, Initializing by Instruction.
253
HD66702
Instructions
Outline
Only the instruction register (IR) and the data register (DR) of the HD66702 can be controlled by the
MPU. Before starting the internal operation of the HD66702, control information is temporarily stored
into these registers to allow interfacing with various MPUs, which operate at different speeds, or various
peripheral control devices. The internal operation of the HD66702 is determined by signals sent from the
MPU. These signals, which include register selection (RS), read/write (R/ ), and the data bus (DB0 to
DB7), make up the HD66702 instructions (Table 7). There are four categories of instructions that:
:
•
•
•
•
Designate HD66702 functions, such as display format, data length, etc.
Set internal RAM addresses
Perform data transfer with internal RAM
Perform miscellaneous functions
Normally, instructions that perform data transfer with internal RAM are used the most. However, autoincrementation by 1 (or auto-decrementation by 1) of internal HD66702 RAM addresses after each data
write can lighten the program load of the MPU. Since the display shift instruction (Table 12) can perform
concurrently with display data write, the user can minimize system development time with maximum
programming efficiency.
When an instruction is being executed for internal operation, no instruction other than the busy
flag/address read instruction can be executed.
Because the busy flag is set to 1 while an instruction is being executed, check it to make sure it is 0
before sending another instruction from the MPU.
Note: Be sure the HD66702 is not in the busy state (BF = 0) before sending an instruction from the
MPU to the HD66702. If an instruction is sent without checking the busy flag, the time between
the first instruction and next instruction will take much longer than the instruction time itself.
Refer to Table 7 for the list of each instruction execution time.
254
HD66702
Table 7
Instructions
:
Execution Time
(max) (when fcp or
Code
Instruction RS
R/
DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 Description
fOSC is 320 kHz)
Clear
display
0
0
0
0
0
0
0
0
0
1
Clears entire display and
sets DDRAM address 0 in
address counter.
1.28 ms
Return
home
0
0
0
0
0
0
0
0
1
—
Sets DDRAM address 0 in
address counter. Also
returns display from being
shifted to original position.
DDRAM contents remain
unchanged.
1.28 ms
Entry mode 0
set
0
0
0
0
0
0
1
I/D
S
Sets cursor move direction
and specifies display shift.
These operations are
performed during data write
and read.
31 µs
Display
on/off
control
0
0
0
0
0
0
1
D
C
B
Sets entire display (D) on/off, 31 µs
cursor on/off (C), and
blinking of cursor position
character (B).
Cursor or
0
display shift
0
0
0
0
1
S/C
R/L
—
—
Moves cursor and shifts
display without changing
DDRAM contents.
Function
set
0
0
0
0
1
DL
N
F
—
—
Sets interface data length
31 µs
(DL), number of display lines
(L), and character font (F).
Set
CGRAM
address
0
0
0
1
ACG ACG ACG ACG ACG ACG Sets CGRAM address.
CGRAM data is sent and
received after this setting.
31 µs
Set
DDRAM
address
0
0
1
ADD ADD ADD ADD ADD ADD ADD Sets DDRAM address.
DDRAM data is sent and
received after this setting.
31 µs
Read busy
flag &
address
0
1
BF
AC
0 µs
AC
AC
AC
AC
AC
AC
Reads busy flag (BF)
indicating internal operation
is being performed and
reads address counter
contents.
31 µs
255
HD66702
Table 7
Instructions (cont)
:
Execution Time
(max) (when fcp or
Code
Instruction RS
R/
DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 Description
fOSC is 320 kHz)
Write data
to CG or
DDRAM
1
0
Write data
Writes data into DDRAM
or CGRAM.
31 µs
tADD = 4.7 µs*
Read data 1
from CG or
DDRAM
1
Read data
Reads data from DDRAM
or CGRAM.
31 µs
tADD = 4.7 µs*
DDRAM: Display data
RAM
CGRAM: Character
generator RAM
ACG: CGRAM address
ADD: DDRAM address
(corresponds to
cursor address)
AC: Address counter
used for both DD and
CGRAM addresses
Execution time
changes when
frequency changes
Example:
When fcp or fOSC
is 270 kHz,
I/D
I/D
S
S/C
S/C
R/L
R/L
DL
N
F
BF
BF
Note:
= 1:
= 0:
= 1:
= 1:
= 0:
= 1:
= 0:
= 1:
= 1:
= 1:
= 1:
= 0:
Increment
Decrement
Accompanies display shift
Display shift
Cursor move
Shift to the right
Shift to the left
8 bits, DL = 0: 4 bits
2 lines, N = 0: 1 line
5 × 10 dots, F = 0: 5 × 7 dots
Internally operating
Instructions acceptable
320
= 37 µs
270
— indicates no effect.
* After execution of the CGRAM/DDRAM data write or read instruction, the RAM address counter
is incremented or decremented by 1. The RAM address counter is updated after the busy flag
turns off. In Figure 10, tADD is the time elapsed after the busy flag turns off until the address
counter is updated.
Busy signal
(DB7 pin)
Busy state
Address counter
(DB0 to DB6 pins)
A
A+1
t ADD
Note: t ADD depends on the operation frequency
t ADD = 1.5/(f cp or f OSC ) seconds
Figure 10 Address Counter Update
256
31 µs ×
HD66702
Instruction Description
Clear Display
Clear display writes space code 20H (character pattern for character code 20H must be a blank pattern)
into all DDRAM addresses. It then sets DDRAM address 0 into the address counter, and returns the
display to its original status if it was shifted. In other words, the display disappears and the cursor or
blinking goes to the left edge of the display (in the first line if 2 lines are displayed). It also sets I/D to 1
(increment mode) in entry mode. S of entry mode does not change.
Return Home
Return home sets DDRAM address 0 into the address counter, and returns the display to its original status
if it was shifted. The DDRAM contents do not change.
The cursor or blinking go to the left edge of the display (in the first line if 2 lines are displayed).
Entry Mode Set
I/D: Increments (I/D = 1) or decrements (I/D = 0) the DDRAM address by 1 when a character code is
written into or read from DDRAM.
The cursor or blinking moves to the right when incremented by 1 and to the left when decremented by 1.
The same applies to writing and reading of CGRAM.
S: Shifts the entire display either to the right (I/D = 0) or to the left (I/D = 1) when S is 1. The display
does not shift if S is 0.
If S is 1, it will seem as if the cursor does not move but the display does. The display does not shift when
reading from DDRAM. Also, writing into or reading out from CGRAM does not shift the display.
Display On/Off Control
D: The display is on when D is 1 and off when D is 0. When off, the display data remains in DDRAM,
but can be displayed instantly by setting D to 1.
C: The cursor is displayed when C is 1 and not displayed when C is 0. Even if the cursor disappears, the
function of I/D or other specifications will not change during display data write. The cursor is displayed
using 5 dots in the 8th line for 5 × 7 dot character font selection and in the 11th line for the 5 × 10 dot
character font selection (Figure 13).
257
HD66702
B: The character indicated by the cursor blinks when B is 1 (Figure 13). The blinking is displayed as
switching between all blank dots and displayed characters at a speed of 320-ms intervals when f cp or fOSC is
320 kHz. The cursor and blinking can be set to display simultaneously. (The blinking frequency changes
according to fOSC or the reciprocal of fcp. For example, when fcp is 270 kHz, 320 × 320/270 = 379.2 ms.)
Cursor or Display Shift
Cursor or display shift shifts the cursor position or display to the right or left without writing or reading
display data (Table 8). This function is used to correct or search the display. In a 2-line display, the
cursor moves to the second line when it passes the 40th digit of the first line. Note that the first and
second line displays will shift at the same time.
When the displayed data is shifted repeatedly each line moves only horizontally. The second line display
does not shift into the first line position.
The address counter (AC) contents will not change if the only action performed is a display shift.
Function Set
DL: Sets the interface data length. Data is sent or received in 8-bit lengths (DB7 to DB0) when DL is 1,
and in 4-bit lengths (DB7 to DB4) when DL is 0.
When 4-bit length is selected, data must be sent or received twice.
N: Sets the number of display lines (Table 9).
F: Sets the character font (Table 9).
Note: Perform the function at the head of the program before executing any instructions (except for the
read busy flag and address instruction). From this point, the function set instruction cannot be
executed unless the interface data length is changed.
Set CGRAM Address
Set CGRAM address sets the CGRAM address binary AAAAAA into the address counter.
Data is then written to or read from the MPU for CGRAM.
258
HD66702
RS
Clear
display
Code
0
RS
Return
home
Code
0
RS
Entry
mode set
Code
0
RS
Display
on/off control
Code
0
R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0
0
0
0
0
0
0
0
1
R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0
0
0
0
0
0
0
1
*
Note: * Don’t care.
R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0
0
0
0
0
0
1
I/D
S
R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0
0
0
0
0
1
D
C
B
Figure 11
RS
Cursor or
display shift
Code
0
RS
Function set
Code
0
RS
Set CGRAM
address
Code
0
R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0
0
0
0
1
S/C
R/L
*
*
Note: * Don’t care.
R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0
0
0
1
DL
N
F
*
*
Note: * Don’t care.
R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0
0
1
A
A
Highest
order bit
A
A
A
A
Lowest
order bit
Figure 12
259
HD66702
Set DDRAM Address
Set DDRAM address sets the DDRAM address binary AAAAAAA into the address counter.
Data is then written to or read from the MPU for DDRAM.
However, when N is 0 (1-line display), AAAAAAA can be 00H to 4FH. When N is 1 (2-line display),
AAAAAAA can be 00H to 27H for the first line, and 40H to 67H for the second line.
Read Busy Flag and Address
Read busy flag and address reads the busy flag (BF) indicating that the system is now internally operating
on a previously received instruction. If BF is 1, the internal operation is in progress. The next instruction
will not be accepted until BF is reset to 0. Check the BF status before the next write operation. At the
same time, the value of the address counter in binary AAAAAAA is read out. This address counter is
used by both CG and DDRAM addresses, and its value is determined by the previous instruction. The
address contents are the same as for instructions set CGRAM address and set DDRAM address.
Table 8
Shift Function
S/C
R/L
0
0
Shifts the cursor position to the left. (AC is decremented by one.)
0
1
Shifts the cursor position to the right. (AC is incremented by one.)
1
0
Shifts the entire display to the left. The cursor follows the display shift.
1
1
Shifts the entire display to the right. The cursor follows the display shift.
Table 9
Function Set
N
F
No. of
Display
Lines
0
0
1
5 × 7 dots
1/8
0
1
1
5 × 10 dots
1/11
1
*
2
5 × 7 dots
1/16
Note:
260
*
Character
Font
Duty
Factor Remarks
Indicates don’t care.
Cannot display two lines for 5 × 10 dot character font.
HD66702
Cursor
5 × 7 dot
character font
5 × 10 dot
character font
Alternating display
Cursor display example
Blink display example
Figure 13 Cursor and Blinking
RS
Set DDRAM
address
Code
0
R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0
1
A
A
A
A
A
A
Highest
order bit
RS
Read busy flag
and address
Code
0
A
Lowest
order bit
R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
1
BF
A
Highest
order bit
A
A
A
A
A
A
Lowest
order bit
Figure 14
261
HD66702
Write Data to CG or DDRAM
Write data to CG or DDRAM writes 8-bit binary data DDDDDDDD to CG or DDRAM.
To write into CG or DDRAM is determined by the previous specification of the CGRAM or DDRAM
address setting. After a write, the address is automatically incremented or decremented by 1 according to
the entry mode. The entry mode also determines the display shift.
Read Data from CG or DDRAM
Read data from CG or DDRAM reads 8-bit binary data DDDDDDDD from CG or DDRAM.
The previous designation determines whether CG or DDRAM is to be read. Before entering this read
instruction, either CGRAM or DDRAM address set instruction must be executed. If not executed, the first
read data will be invalid. When serially executing read instructions, the next address data is normally
read from the second read. The address set instructions need not be executed just before this read
instruction when shifting the cursor by the cursor shift instruction (when reading out DDRAM). The
operation of the cursor shift instruction is the same as the set DDRAM address instruction.
After a read, the entry mode automatically increases or decreases the address by 1. However, display shift
is not executed regardless of the entry mode.
Note: The address counter (AC) is automatically incremented or decremented by 1 after the write
instructions to CGRAM or DDRAM are executed. The RAM data selected by the AC cannot be
read out at this time even if read instructions are executed. Therefore, to correctly read data,
execute either the address set instruction or cursor shift instruction (only with DDRAM), then just
before reading the desired data, execute the read instruction from the second time the read
instruction is sent.
RS
Write data to
CG or DDRAM
Code
1
R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0
D
D
D
D
D
Higher
order bits
RS
Read data from
CG or DDRAM
Code
1
D
D
Lower
order bits
R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
1
D
D
Higher
order bits
Figure 15
262
D
D
D
D
D
D
Lower
order bits
D
HD66702
Interfacing the HD66702
Interface to MPUs
• Interfacing to an 8-bit MPU
See Figure 17 for an example of using a I/O port (for a single-chip microcomputer) as an interface
device.
In this example, A0 to A7 are connected to the data bus DB0 to DB7, and C0 to C2 are connected to
E, R/ , and RS, respectively.
:
RS
R/W
E
Internal
operation
Functioning
Data
Busy
Busy
Instruction
write
Busy flag
check
Busy flag
check
DB7
Not
busy
Data
Busy flag
check
Instruction
write
Figure 16 Example of Busy Flag Check Timing Sequence
H8/325
HD66702
C0
C1
C2
RS
R/W
E
DB0 to DB7
A0 to A7
8
COM1 to
COM16
16
SEG1 to
SEG100
100
LCD
Figure 17 8-bit MPU Interface
263
HD66702
• Interfacing to a 4-bit MPU
The HD66702 can be connected to the I/O port of a 4-bit MPU. If the I/O port has enough bits, 8-bit
data can be transferred. Otherwise, one data transfer must be made in two operations for 4-bit data. In
this case, the timing sequence becomes somewhat complex. (See Figure 18.)
See Figure 19 for an interface example to the HMCS43C.
Note that two cycles are needed for the busy flag check as well as for the data transfer. The 4-bit
operation is selected by the program.
RS
R/W
E
Internal
operation
DB7
Functioning
IR7
IR3
Instruction
write
Busy AC3
Not
busy AC3
Busy flag
check
Busy flag
check
D7
D3
Instruction
write
Note: * IR7, IR3 are the 7th and 3rd bits of the instruction.
AC3 is the 3rd bit of the address counter.
Figure 18 Example of 4-Bit Data Transfer Timing Sequence
HMCS43C
(Hitachi 4-bit single-chip
microcontroller)
HD66702
D15
RS
D14
R/W
D13
E
4
R10 to R13
COM1 to
COM16
16
LCD
SEG1 to 100
DB4 to DB7
SEG100
Figure 19 Example of Interface to HMCS43C
264
HD66702
Interface to Liquid Crystal Display
Character Font and Number of Lines: The HD66702 can perform two types of displays, 5 × 7 dot and
5 × 10 dot character fonts, each with a cursor.
Up to two lines are displayed for 5 × 7 dots and one line for 5 × 10 dots. Therefore, a total of three types
of common signals are available (Table 10).
The number of lines and font types can be selected by the program. (See Table 7, Instructions.)
Connection to HD66702 and Liquid Crystal Display: See Figure 20 for the connection examples.
Table 10
Common Signals
Number of Lines
Character Font
Number of Common Signals
Duty Factor
1
5 × 7 dots + cursor
8
1/8
1
5 × 10 dots + cursor
11
1/11
2
5 × 7 dots + cursor
16
1/16
HD66702
COM1
COM8
SEG1
SEG100
Example of a 5 × 7 dot, 20-character × 1-line display (1/4 bias, 1/8 duty cycle)
HD66702
COM1
COM11
SEG1
SEG100
Example of a 5 × 10 dot, 20-character × 1-line display (1/4 bias, 1/8 duty cycle)
Figure 20 Liquid Crystal Display and HD66702 Connections
265
HD66702
Since five segment signal lines can display one digit, one HD66702 can display up to 20 digits for a 1line display and 40 digits for a 2-line display.
The examples in Figure 20 have unused common signal pins, which always output non-selection
waveforms. When the liquid crystal display panel has unused extra scanning lines, connect the extra
scanning lines to these common signal pins to avoid any undesirable effects due to crosstalk during the
floating state (Figure 21).
HD66702
COM1
COM8
COM9
COM16
SEG1
SEG100
Example of a 5 × 7 dot, 20-character × 2-line display (1/5 bias, 1/16 duty cycle)
Figure 20 Liquid Crystal Display and HD66702 Connections (cont)
HD66702
COM1
COM8
COM9
SEG1
SEG100
5 × 7 dot, 20-character × 1-line display (1/4 bias, 1/8 duty cycle)
Figure 21 Using COM9 to Avoid Crosstalk on Unneeded Scanning Line
266
HD66702
Connection of Changed Matrix Layout: In the preceding examples, the number of lines correspond to
the scanning lines. However, the following display examples (Figure 22) are made possible by altering
the matrix layout of the liquid crystal display panel. In either case, the only change is the layout. The
display characteristics and the number of liquid crystal display characters depend on the number of
common signals or on duty factor. Note that the display data RAM (DDRAM) addresses for 10 characters
× 2 lines and for 40 characters × 1 line are the same as in Figure 20.
HD66702
COM1
COM8
SEG1
SEG100
COM9
COM16
HD66702
5 × 7 dot, 40-character × 1-line display
(1/5 bias, 1/16 duty cycle)
SEG1
SEG50
COM1
COM8
SEG51
SEG100
5 × 7 dot, 10-character × 2-line display
(1/4 bias, 1/8 duty cycle)
Figure 22 Changed Matrix Layout Displays
267
HD66702
Power Supply for Liquid Crystal Display Drive
Various voltage levels must be applied to pins V1 to V5 of the HD66702 to obtain the liquid crystal
display drive waveforms. The voltages must be changed according to the duty factor (Table 11).
VLCD is the peak value for the liquid crystal display drive waveforms, and resistance dividing provides
voltages V1 to V5 (Figure 23).
Table 11
Duty Factor and Power Supply for Liquid Crystal Display Drive
Duty Factor
1/8, 1/11
1/16
Bias
Power Supply
1/4
1/5
V1
VCC–1/4 VLCD
VCC–1/5 VLCD
V2
VCC–1/2 VLCD
VCC–2/5 VLCD
V3
VCC–1/2 VLCD
VCC–3/5 VLCD
V4
VCC–3/4 VLCD
VCC–4/5 VLCD
V5
VCC–VLCD
VCC–VLCD
VCC
HD66702
VCC
HD66702
VCC
VCC
R
R
R
V2
VLCD
V3
R
V4
R
V5
R
V1
V1
V2
R
V3
R
V4
R
V5
VR
VR
1/4 bias
(1/8, 1/11 duty cycle)
VEE
1/5 bias
(1/16, duty cycle)
VEE
Note: R changes depending on the size of liquid crystal panel.
Normally, R is, 4.7 kΩ to 20kΩ.
Figure 23 Drive Voltage Supply Example
268
VLCD
HD66702
Relationship between Oscillation Frequency and Liquid Crystal Display Frame
Frequency
The liquid crystal display frame frequencies of Figure 24 apply only when the oscillation frequency is
320 kHz (one clock pulse of 3.125 µs).
1/8 duty cycle
COM1
400 clocks
1
2
3
4
8
1
2
11
1
2
1
2
VCC
V1
V2 (V3)
V4
V5
1 frame
1 frame = 3.125 µs × 400 × 8 = 10000 µs = 10 ms
1
Frame frequency =
= 100 Hz
10 ms
1/11 duty cycle
COM1
400 clocks
1
2
3
4
VCC
V1
V2 (V3)
V4
V5
1 frame
1 frame = 3.125 µs × 400 × 11 = 13750 µs = 13.75 ms
1
Frame frequency =
= 72.7 Hz
13.75 ms
1/16 duty cycle
COM1
200 clocks
1
2
3
4
16
VCC
V1
V2
V3
V4
V5
1 frame
1 frame = 3.125 µs × 200 × 16 = 10000 µs = 10 ms
1
Frame frequency =
= 100 Hz
10 ms
Figure 24 Frame Frequency
269
HD66702
Instruction and Display Correspondence
• 8-bit operation, 20-digit × 1-line display with internal reset
Refer to Table 12 for an example of an 8-bit × 1-line display in 8-bit operation. The HD66702
functions must be set by the function set instruction prior to the display. Since the display data RAM
can store data for 80 characters, as explained before, the RAM can be used for displays such as for
advertising when combined with the display shift operation.
Since the display shift operation changes only the display position with DDRAM contents unchanged,
the first display data entered into DDRAM can be output when the return home operation is
performed.
• 4-bit operation, 20-digit × 1-line display with internal reset
The program must set all functions prior to the 4-bit operation (Table 13). When the power is turned
on, 8-bit operation is automatically selected and the first write is performed as an 8-bit operation.
Since DB0 to DB3 are not connected, a rewrite is then required. However, since one operation is
completed in two accesses for 4-bit operation, a rewrite is needed to set the functions (see Table 13).
Thus, DB4 to DB7 of the function set instruction is written twice.
• 8-bit operation, 20-digit × 2-line display
For a 2-line display, the cursor automatically moves from the first to the second line after the 40th
digit of the first line has been written. Thus, if there are only 20 characters in the first line, the
DDRAM address must be again set after the 20th character is completed. (See Table 14.) Note that
the display shift operation is performed for the first and second lines. In the example of Table 14, the
display shift is performed when the cursor is on the second line. However, if the shift operation is
performed when the cursor is on the first line, both the first and second lines move together. If the
shift is repeated, the display of the second line will not move to the first line. The same display will
only shift within its own line for the number of times the shift is repeated.
Note: When using the internal reset, the electrical characteristics in the Power Supply Conditions Using
Internal Reset Circuit table must be satisfied. If not, the HD66702 must be initialized by
instructions. (Because the internal reset does not function correctly when VCC is 3V, it must
always be initialized by software.) See the section, Initializing by Instruction.
270
HD66702
8-Bit Operation, 20-Digit × 1-Line Display Example with Internal Reset
Table 12
Step
No. RS
Instruction
:
R/
DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 Display
Operation
1
Power supply on (the HD66702 is initialized by the internal reset
circuit)
Initialized. No display.
2
Function set
0
0
0
Sets to 8-bit operation and
selects 1-line display and
character font. (Number of
display lines and character fonts
cannot be changed after step
#2.)
3
4
5
6
0
1
1
0
0
*
*
Display on/off control
0
0
0
0
0
0
1
1
1
0
Entry mode set
0
0
0
0
0
0
1
1
0
Write data to CGRAM/DDRAM
1
0
0
1
0
0
1
0
0
0
Write data to CGRAM/DDRAM
1
0
0
1
0
0
1
0
0
1
0
7
8
9
10
Writes H. DDRAM already been
selected by initialization when
the power was turned on. The
cursor is incremented by one
and shifted to the right.
H_
Writes I.
HI_
·
·
·
·
·
Write data to CGRAM/DDRAM
1
0
0
1
0
0
1
0
0
1
Entry mode set
0
0
0
0
0
1
1
1
Write data to CGRAM/DDRAM
1
0
0
0
1
0
0
0
0
0
0
Sets mode to increment the
address by one and to shift the
cursor to the right at the time of
write to the DD/CGRAM.
Display is not shifted.
_
·
·
·
·
·
0
Turns on display and cursor.
Entire display is in space mode
becauce of initialization.
_
HITACHI_
HITACHI_
ITACHI _
Writes I.
Sets mode to shift display at the
time of write.
Writes a space.
271
HD66702
8-Bit Operation, 20-Digit × 1-Line Display Example with Internal Reset (cont)
Table 12
Step
No. RS
11
Instruction
:
R/
DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 Display
Write data to CGRAM/DDRAM
1
0
0
1
0
0
12
13
14
15
16
17
18
19
272
1
0
1
·
·
·
·
·
Write data to CGRAM/DDRAM
1
0
0
1
0
0
1
1
1
1
Cursor or display shift
0
0
0
0
0
1
0
0
*
*
Cursor or display shift
0
0
0
0
0
1
0
0
*
*
Write data to CGRAM/DDRAM
1
0
0
1
0
0
0
0
1
1
Cursor or display shift
0
0
0
0
0
1
1
1
*
*
Cursor or display shift
0
0
0
0
0
1
0
1
*
*
Write data to CGRAM/DDRAM
1
0
0
1
0
0
1
1
0
1
MICROKO_
0
0
Writes O.
MICROKO
_
Shifts only the cursor position to
the left.
MICROKO
_
Shifts only the cursor position to
the left.
ICROCO
_
Writes C over K.
The display moves to the left.
MICROCO
_
Shifts the display and cursor
position to the right.
MICROCO_
Shifts the display and cursor
position to the right.
ICROCOM_
·
·
·
·
·
Return home
0
0
0
Writes M.
TACHI M_
·
·
·
·
·
20
21
1
Operation
Writes M.
·
·
·
·
·
0
0
0
1
0
HITACHI
_
Returns both display and cursor
to the original position(address
0).
HD66702
4-Bit Operation, 20-Digit × 1-Line Display Example with Internal Reset
Table 13
Step
No. RS
Instruction
:
R/
DB7 DB6 DB5 DB4
Display
Operation
1
Power supply on (the HD66702 is initialized by the internal reset
circuit)
Initialized. No display.
2
Function set
0
0
0
0
1
0
Sets to 4-bit operation.
In this case, operation is
handled as 8 bits by initialization, and only this instruction
completes with one write.
Function set
0
0
0
0
0
0
0
0
1
*
0
*
Display on/off control
0
0
0
0
0
0
1
1
0
1
0
0
Entry mode set
0
0
0
0
0
0
0
1
0
0
3
4
5
6
0
1
Write data to CGRAM/DDRAM
1
0
0
1
0
0
1
0
1
0
0
0
Sets 4-bit operation and
selects1-line display and 5 × 7
dot character font. 4-bit
operation starts from this step
and resetting is necessary.
(Number of display lines and
character fonts cannot be
changed after step #3.)
_
_
H_
Turns on display and cursor.
Entire display is in space mode
because of initialization.
Sets mode to increment the
address by one and to shift the
cursor to the right at the time of
write to the DD/CGRAM.
Display is not shifted.
Writes H.
The cursor is incremented by
one and shifts to the right.
Note: The control is the same as for 8-bit operation beyond step #6.
273
HD66702
8-Bit Operation, 20-Digit × 2-Line Display Example with Internal Reset
Table 14
Step
No. RS
Instruction
:
R/
DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 Display
Operation
1
Power supply on (the HD66702 is initialized by the internal reset
circuit)
Initialized. No display.
2
Function set
0
0
0
Sets to 8-bit operation and
selects 2-line display and
5 × 7 dot character font.
3
4
5
0
1
1
1
0
*
*
Display on/off control
0
0
0
0
0
0
1
1
1
0
Entry mode set
0
0
0
0
0
0
1
1
0
Write data to CGRAM/DDRAM
1
0
0
1
0
0
1
0
0
0
8
274
Sets mode to increment the
address by one and to shift the
cursor to the right at the time of
write to the DD/CGRAM.
Display is not shifted.
_
0
6
7
Turns on display and cursor.
All display is in space mode
because of initialization.
_
·
·
·
·
·
·
·
·
·
·
Write data to CGRAM/DDRAM
1
0
0
1
0
0
1
0
0
1
Set DDRAM address
0
0
1
1
0
0
0
0
0
Writes H. DDRAM has already
been selected by initialization
when the power was turned on.
The cursor is incremented by
one and shifted to the right.
H_
0
HITACHI_
HITACHI
_
Writes I.
Sets RAM address so that the
cursor is positioned at the head
of the second line.
HD66702
8-Bit Operation, 20-Digit × 2-Line Display Example with Internal Reset (cont)
Table 14
Step
No. RS
9
Instruction
:
R/
DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 Display
Write data to CGRAM/DDRAM
1
0
0
1
0
0
10
11
12
13
1
0
1
·
·
·
·
·
Writes M.
HITACHI
M_
·
·
·
·
·
Write data to CGRAM/DDRAM
1
0
0
1
0
0
1
1
1
1
HITACHI
MICROCO_
Entry mode set
0
0
0
0
0
1
1
1
HITACHI
MICROCO_
Write data to CGRAM/DDRAM
1
0
0
1
0
0
1
1
0
1
ITACHI
ICROCOM_
0
0
14
15
1
Operation
·
·
·
·
·
Return home
0
0
0
0
0
Writes O.
Sets mode to shift display at the
time of write.
Writes M. Display is shifted to
the right. The first and second
lines both shift at the same time.
·
·
·
·
·
0
0
0
1
0
HITACHI
_
MICROCOM
Returns both display and cursor
to the original position (address
0).
275
HD66702
Initializing by Instruction
If the power supply conditions for correctly operating the internal reset circuit are not met, initialization
by instructions becomes necessary.
Refer to Figures 25 and 26 for the procedures on 8-bit and 4-bit initializations, respectively.
Power on
Wait for more than 40 ms
after VCC rises to 2.7V
Wait for more than 15 ms
after VCC rises to 4.5V
RS R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0 0 0 0 1 1 * * * *
BF cannot be checked before this instruction.
Function set (Interface is 8 bits long.)
Wait for more than 4.1 ms
RS R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0 0 0 0 1 1 * * * *
BF cannot be checked before this instruction.
Function set (Interface is 8 bits long.)
Wait for more than 100 µs
RS R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0 0 0 0 1 1 * * * *
BF cannot be checked before this instruction.
Function set (Interface is 8 bits long.)
BF can be checked after the following instructions.
When BF is not checked, the waiting time between
instructions is longer than the execution instuction
time. (See Table 7.)
RS R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0 0 0 0 1 1 N F * *
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
1
I/D S
Function set (Interface is 8 bits long. Specify the
number of display lines and character font.)
The number of display lines and character font
cannot be changed after this point.
Display off
Display clear
Entry mode set
Initialization ends
Figure 25 8-Bit Interface
276
HD66702
Power on
Wait for more than 15 ms
after VCC rises to 4.5V
RS R/W DB7 DB6 DB5 DB4
0 0 0 0 1 1
Wait for more than 40 ms
after VCC rises to 2.7V
BF cannot be checked before this instruction.
Function set (Interface is 8 bits long.)
Wait for more than 4.1 ms
RS R/W DB7 DB6 DB5 DB4
0 0 0 0 1 1
BF cannot be checked before this instruction.
Function set (Interface is 8 bits long.)
Wait for more than 100 µs
RS R/W DB7 DB6 DB5 DB4
0 0 0 0 1 1
BF cannot be checked before this instruction.
RS R/W DB7 DB6 DB5 DB4
0 0 0 0 1 0
BF can be checked after the following instructions.
When BF is not checked, the waiting time between
instructions is longer than the execution instuction
time. (See Table 7.)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
N
0
1
0
0
0
0
0
F
0
0
0
0
0
1
1 0
* *
0 0
0 0
0 0
0 1
0 0
I/D S
Function set (Interface is 8 bits long.)
Function set (Set interface to be 4 bits long.)
Interface is 8 bits in length.
Function set (Interface is 4 bits long. Specify the
number of display lines and character font.)
The number of display lines and character font
cannot be changed after this point.
Display off
Display clear
Initialization ends
Entry mode set
Figure 26 4-Bit Interface
277
HD66702
[Low voltage version]
Absolute Maximum Ratings*
Item
Symbol
Unit
Value
Notes
Power supply voltage (1)
VCC
V
–0.3 to +7.0
1
Power supply voltage (2)
VCC–V5
V
–0.3 to +8.5
2
Input voltage
Vt
V
–0.3 to VCC +0.3
1
Operating temperature
Topr
°C
–20 to +75
Storage temperature
Tstg
°C
–55 to +125
Note:
278
1. The operating temperature is 75°C.
2. If the LSI is used above these absolute maximum ratings, it may become permanently
damaged. Using the LSI within the following electrical characteristic limits is strongly
recommended for normal operation. If these electrical characteristic conditions are also
exceeded, the LSI will malfunction and cause poor reliability.
3. The power supply voltage is GND = 0V.
4. Keep VCC ≥ V5 (Low), and VCC ≥ GND (Low)
4
HD66702
DC Characteristics (VCC = 2.7 to 5.5V, Ta = –20 to +75°C*3)
Item
Symbol
Min
Typ
Max
Unit
Test Condition
Notes*
Input high voltage (1)
(except OSC1)
VIH1
0.7VCC
—
VCC
V
6, 17
Input low voltage (1)
(except OSC1)
VIL1
–0.3
—
0.55
V
6, 17
Input high voltage (2)
(OSC1)
VIH2
0.7VCC
—
VCC
V
15
Input low voltage (2)
(OSC1)
VIL2
—
—
0.2VCC
V
15
Output high voltage (1) VOH1
(D0–D7)
0.75VCC —
—
V
–IOH = 0.1 mA
7
Output low voltage (1)
(D0–D7)
—
—
0.2VCC
V
IOL = 0.1 mA
7
Output high voltage (2) VOH2
(except D0–D7)
0.8VCC
—
—
V
–IOH = 0.04 mA
8
Output low voltage (2)
(except D0–D7)
VOL2
—
—
0.2VCC
V
IOL = 0.04 mA
8
Driver on resistance
(COM)
RCOM
—
2
20
kΩ
±Id = 0.05 mA (COM)
13
Driver on resistance
(SEG)
RSEG
—
2
30
kΩ
±Id = 0.05 mA (SEG)
13
Input leakage current
ILI
–1
—
1
µA
VIN = 0 to VCC
9
Pull-up MOS current
(RS, R/:, D0–D7)
–Ip
10
50
120
µA
VCC = 3V
Power supply current
ICC
—
0.15
0.30
mA
Rf oscillation,
external clock
VCC = 3V, fOSC = 320 kHz
10, 14
LCD voltage
VLCD1
3.0
—
8.3
V
VCC–V5, 1/5 bias
16
VLCD2
3.0
—
8.3
V
VCC–V5, 1/4 bias
16
Note:
*
VOL1
Refer to the Electrical Characteristics Notes section following these tables.
279
HD66702
AC Characteristics (VCC = 2.7 to 5.5V, Ta = –20 to +75°C*3)
Clock Characteristics
Item
Symbol Min Typ
Max
Unit
External
External clock frequency
fcp
125 270
410
kHz
clock
operation
External clock duty
Duty
45
50
55
%
External clock rise time
trcp
—
—
0.2
µs
External clock fall time
tfcp
—
—
0.2
µs
Clock oscillation
frequency
fOSC
240 320
390
kHz
Rf
oscillation
Note:
*
Test Condition Notes*
11
Rf = 56 kΩ
VCC = 3V
12
Refer to the Electrical Characteristics Notes section following these tables.
Bus Timing Characteristics
Write Operation
Item
Symbol
Min
Typ
Max
Unit
Test Condition
Enable cycle time
tcycE
1000
Enable pulse width (high level)
PWEH
450
—
—
ns
Figure 27
—
—
Enable rise/fall time
tEr, tEf
—
—
25
Address set-up time (RS, R/: to E) tAS
40
—
—
Address hold time
tAH
20
—
—
Data set-up time
tDSW
195
—
—
Data hold time
tH
10
—
—
Item
Symbol
Min
Typ
Max
Unit
Test Condition
Enable cycle time
tcycE
1000
—
—
ns
Figure 28
Enable pulse width (high level)
PWEH
450
—
—
Enable rise/fall time
tEr, tEf
—
—
25
Address set-up time (RS, R/: to E) tAS
40
—
—
Address hold time
tAH
20
—
—
Data delay time
tDDR
—
—
350
Data hold time
tDHR
10
—
—
Read Operation
280
HD66702
Interface Timing Characteristics with External Driver
Item
Symbol
Min
Typ
Max
Unit
Test Condition
High level
tCWH
800
—
—
ns
Figure 29
Low level
tCWL
800
—
—
Clock set-up time
tCSU
500
—
—
Data set-up time
tSU
300
—
—
Data hold time
tDH
300
—
—
M delay time
tDM
–1000
—
1000
Clock rise/fall time
tct
—
—
200
Clock pulse width
Power Supply Conditions Using Internal Reset Circuit
Item
Symbol
Min
Typ
Max
Unit
Test Condition
Power supply rise time
trCC
0.1
—
10
ms
Figure 30
Power supply off time
tOFF
1
—
—
[Standard Voltage Version]
Absolute Maximum Ratings*
Item
Symbol
Unit
Value
Notes
Power supply voltage (1)
VCC
V
–0.3 to +7.0
1
Power supply voltage (2)
VCC–V5
V
–0.3 to +8.5
2
Input voltage
Vt
V
–0.3 to VCC +0.3
1
Operating temperature
Topr
°C
–20 to +75
Storage temperature
Tstg
°C
–55 to +125
Note:
*
4
If the LSI is used above these absolute maximum ratings, it may become permanently
damaged. Using the LSI within the following electrical characteristic limits is strongly
recommended for normal operation. If these electrical characteristic conditions are also
exceeded, the LSI will malfunction and cause poor reliability. Refer to the Electrical
Characteristics Notes section following these tables.
281
HD66702
DC Characteristics (VCC = 5V ±10%, Ta = –20 to +75°C*3)
Item
Symbol
Min
Typ
Max
Unit
Input high voltage (1)
(except OSC1)
VIH1
2.2
—
VCC
V
6, 17
Input low voltage (1)
(except OSC1)
VIL1
–0.3
—
0.6
V
6, 17
Input high voltage (2)
(OSC1)
VIH2
VCC–1.0 —
VCC
V
15
Input low voltage (2)
(OSC1)
VIL2
—
—
1.0
V
15
Output high voltage (1) VOH1
(D0–D7)
2.4
—
—
V
–IOH = 0.205 mA
7
Output low voltage (1)
(D0–D7)
—
—
0.4
V
IOL = 1.6 mA
7
V
–IOH = 0.04 mA
8
VOL1
Test Condition
Notes*
Output high voltage (2) VOH2
(except D0–D7)
0.9 VCC —
—
Output low voltage (2)
(except D0–D7)
VOL2
—
—
0.1 VCC V
IOL = 0.04 mA
8
Driver on resistance
(COM)
RCOM
—
2
20
kΩ
±Id = 0.05 mA (COM)
13
Driver on resistance
(SEG)
RSEG
—
2
30
kΩ
±Id = 0.05 mA (SEG)
13
Input leakage current
ILI
–1
—
1
µA
VIN = 0 to VCC
9
Pull-up MOS current
(RS, R/:, D0–D7)
–Ip
50
125
250
µA
VCC = 5V
Power supply current
ICC
—
0.35
0.60
mA
Rf oscillation,
external clock
VCC = 5V, fOSC = 320 kHz
10, 14
LCD voltage
VLCD1
3.0
—
8.3
V
VCC–V5, 1/5 bias
16
VLCD2
3.0
—
8.3
V
VCC–V5, 1/4 bias
16
Note:
282
*
Refer to the Electrical Characteristics Notes section following these tables.
HD66702
AC Characteristics (VCC = 5V ±10%, Ta = –20 to +75°C*3)
Clock Characteristics
Item
Symbol
Min
Typ
Max
Unit
Test Condition Notes*
External
External clock frequency
fcp
125
270
410
kHz
11
clock
External clock duty
Duty
45
50
55
%
11
operation
External clock rise time
trcp
—
—
0.2
µs
11
External clock fall time
tfcp
—
—
0.2
µs
11
Clock oscillation frequency
fOSC
220
320
420
kHz
Rf
oscillation
Note:
*
Rf = 68 kΩ
VCC = 5V
12
Refer to the Electrical Characteristics Notes section following these tables.
Bus Timing Characteristics
Write Operation
Item
Symbol
Min
Typ
Max
Unit
Test Condition
Enable cycle time
tcycE
1000
—
—
ns
Figure 27
Enable pulse width (high level)
PWEH
450
—
—
Enable rise/fall time
tEr, tEf
—
—
25
Address set-up time (RS, R/:to E) tAS
40
—
—
Address hold time
tAH
10
—
—
Data set-up time
tDSW
195
—
—
Data hold time
tH
10
—
—
Symbol
Min
Typ
Max
Unit
Test Condition
Enable cycle time
tcycE
1000
—
—
ns
Figure 28
Enable pulse width (high level)
PWEH
450
—
—
Enable rise/fall time
tEr, tEf
—
—
25
Address set-up time (RS, R/: to E) tAS
40
—
—
Address hold time
tAH
10
—
—
Data delay time
tDDR
—
—
320
Data hold time
tDHR
20
—
—
Read Operation
Item
283
HD66702
Interface Timing Characteristics with External Driver
Item
Symbol
Min
Typ
Max
Unit
Test Condition
High level
tCWH
800
—
—
ns
Figure 29
Low level
tCWL
800
—
—
Clock set-up time
tCSU
500
—
—
Data set-up time
tSU
300
—
—
Data hold time
tDH
300
—
—
M delay time
tDM
–1000
—
1000
Clock rise/fall time
tct
—
—
100
Clock pulse width
Power Supply Conditions Using Internal Reset Circuit
Item
Symbol
Min
Typ
Max
Unit
Test Condition
Power supply rise time
trCC
0.1
—
10
ms
Figure 30
Power supply off time
tOFF
1
—
—
284
HD66702
Electrical Characteristics Notes
1.
2.
3.
4.
5.
All voltage values are referred to GND = 0V.
VCC ≥ V5 must be maintained.
For die products, specified up to 75°C.
For die products, specified by the die shipment specification.
The following four circuits are I/O pin configurations except for liquid crystal display output.
Input pin
Pin: E (MOS without pull-up)
Output pin
Pins: CL1 , CL2 , M, D
Pins: RS, R/W (MOS with pull-up)
VCC
VCC
VCC
PMOS
PMOS
VCC
PMOS
PMOS
NMOS
NMOS
(pull up MOS)
NMOS
I/O Pin
Pins: DB0 –DB7
(MOS with pull-up)
VCC
(pull-up MOS)
VCC
(input circuit)
PMOS
PMOS
Input enable
NMOS
VCC
NMOS
PMOS
Output enable
Data
NMOS
(output circuit)
(tristate)
285
HD66702
6. Applies to input pins and I/O pins, excluding the OSC1 pin.
7. Applies to I/O pins.
8. Applies to output pins.
9. Current flowing through pull–up MOSs, excluding output drive MOSs.
10. Input/output current is excluded. When input is at an intermediate level with CMOS, the excessive
current flows through the input circuit to the power supply. To avoid this from happening, the input
level must be fixed high or low.
11. Applies only to external clock operation.
Th
Oscillator
Tl
OSC1
Open
0.7 VCC
0.5 VCC
0.3 VCC
OSC2
trcp
trcp
Th
× 100%
Duty =
Th + Tl
12. Applies only to the internal oscillator operation using oscillation resistor Rf.
R f : 56 k Ω ± 2% (when VCC = 3V)
R f : 68 k Ω ± 2% (when VCC = 5V)
Since the oscillation frequency varies depending on the OSC1 and
OSC2 pin capacitance, the wiring length to these pins should be minimized.
OSC1
Rf
OSC2
VCC = 3V
500
400
400
320
300
max.
200
typ.
fOSC (kHz)
fOSC (kHz)
VCC = 5V
500
320
300
max.
200
typ.
min.
100
50
(68)
100
Rf (k Ω)
286
150
100
min.
50
(56)
100
Rf (k Ω)
150
HD66702
13. RCOM is the resistance between the power supply pins (VCC, V1, V4, V5) and each common signal pin
(COM1 to COM16).
RSEG is the resistance between the power supply pins (VCC, V2, V3, V5) and each segment signal pin
(SEG1 to SEG100).
14. The following graphs show the relationship between operation frequency and current consumption.
VCC = 3V
1.8
1.6
1.6
1.4
1.4
1.2
1.0
max.
0.8
typ.
0.6
I CC (mA)
I CC (mA)
VCC = 5V
1.8
1.2
1.0
0.8
0.6
0.4
0.4
0.2
0.2
0.0
0.0
0
100
200
300
f OSC or f cp (kHz)
400
500
max.
typ.
0
100
200
300
400
500
f OSC or f cp (kHz)
15. Applies to the OSC1 pin.
16. Each COM and SEG output voltage is within ±0.15V of the LCD voltage (VCC, V1, V2, V3, V4, V5)
when there is no load.
17. The TEST pin should be fixed to GND and the EXT pin should be fixed to VCC or GND.
287
HD66702
Load Circuits
Data Bus DB0 to DB7
VCC = 5V
For VCC = 5V
For VCC = 3V
2.4 k Ω
Test
point
Test
point
90 pF
11 k Ω
1S2074
diodes H
External Driver Control Signal: CL1, CL2, D, M
Test
point
30 pF
288
50 pF
HD66702
Timing Characteristics
RS
VIH1
VIL1
VIH1
VIL1
t AS
R/W
t AH
VIL1
VIL1
PWEH
t AH
t Ef
VIH1
VIL1
E
VIH1
VIL1
t Er
VIH1
VIL1
DB0 to DB7
VIL1
tH
t DSW
VIH1
VIL1
Valid data
t cycE
Figure 27 Write Operation
RS
VIH1
VIL1
VIH1
VIL1
t AS
R/W
t AH
VIH1
VIH1
PWEH
t AH
t Ef
E
VIH1
VIL1
VIH1
VIL1
VIL1
t Er
t DHR
t DDR
DB0 to DB7
VOH1
VOL1
Valid data
VOH1
VOL1
t cycE
Figure 28 Read Operation
289
HD66702
t ct
VOH2
CL1
VOH2
VOL2
t CWH
t CWH
t CSU
CL2
VOH2
VOL2
t CWL
t ct
t CSU
VOH2
VOL2
D
t DH
t SU
M
VOL2
t DM
Figure 29 Interface Timing with External Driver
VCC
2.7V/4.5V
*2
0.2V
0.2V
t rcc
0.1 ms ≤ t rcc ≤ 10 ms
0.2V
t OFF *1
t OFF ≥ 1 ms
Notes: 1. t OFF compensates for the power oscillation period caused by momentary power
supply oscillations.
2. Specified at 4.5V for 5-V operation, and at 2.7V for 3-V operation.
3. When the above condition cannot be satisfied, the internal reset circuit
will not operate normally.
In this case, the LSI must be initialized by software. (Refer to the Initializing
by Instruction section.)
Figure 30 Internal Power Supply Reset
290