ST Sitronix ST7066 Dot Matrix LCD Controller/Driver Features !" 16-common x 40-segment liquid crystal display driver !" Programmable duty cycles -- 1/8 for one line of 5 x 8 dots with cursor -- 1/11 for one line of 5 x 11 dots & cursor -- 1/16 for two lines of 5 x 8 dots & cursor !" Wide range of instruction functions: Display clear, cursor home, display on/off, cursor on/off, display character blink, cursor shift, display shift !" Pin function compatibility with HD44780, KS0066 and SED1278 !" Automatic reset circuit that initializes the controller/driver after power on !" Internal oscillator with external resistors !" Low power consumption !" QFP80 and Bare Chip available !" 5 x 8 and 5 x 11 dot matrix possible !" Low power operation support: -- 2.7 to 5.5V !" Wide range of LCD driver power -- 3.0 to 11V !" Correspond to high speed MPU bus interface -- 2 MHz (when VCC = 5V) !" 4-bit or 8-bit MPU interface enabled !" 80 x 8-bit display RAM (80 characters max.) !" 9,920-bit character generator ROM for a total of 240 character fonts -- 208 character fonts (5 x 8 dot) -- 32 character fonts (5 x 11 dot) !" 64 x 8-bit character generator RAM -- 8 character fonts (5 x 8 dot) -- 4 character fonts (5 x 11 dot) Description The ST7066 dot-matrix liquid crystal display controller and driver LSI displays alphanumeric, 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 such as display RAM, character generator, and liquid crystal driver, 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. 208 5 x 8 dot character fonts and 32 5 x 11 dot character fonts for a total of 240 different character fonts. The low power supply (2.7V to 5.5V) of the ST7066 is suitable for any portable battery-driven product requiring low power dissipation. The ST7066 LCD driver consists of 16 common signal drivers and 40 segment signal drivers which can extend display size by cascading segment driver ST7065 or ST7063. The maximum display size can be either 80 characters in 1-line display or 40 characters in 2-line display. A single ST7066 can display up to one 8-character line or two 8-character lines. The ST7066 has pin function compatibility with the HD44780, KS0066U and SED1278 that allows the user to easily replace it with an ST7066. The ST7066 character generator ROM is extended to generate V1.2 Product Name Support Character ST7066-0A English / Japan ST7066-0B English / European 1 2000/6/13 ST7066 Block Diagram OSC1 OSC2 CL1 CL2 M Reset Circuit CPG Timing Generator D Instruction Register (IR) RS Display data RAM (DDRAM) 80x8 bits MPU Interface RW E 16-bit shift registe r Common Signal Driver 40-bit latch circuit Segment Signal Driver COM1 to COM16 Instruction Decoder 40-bit shift registe r Address Counter DB4 to DB7 DB0 to DB3 Input/ Output Buffer Data Register (DR) SEG1 to SEG40 LCD Drive Voltage Selector Busy Flag Character generator RAM (CGRAM) 64 bits GND Character generator ROM (CGROM) 9,920 bits Cursor and Blink controller Parallel/Serial converter and Attribute Circuit Vcc V1 V1.2 V2 2 V3 V4 V5 2000/6/13 ST7066 Pad Arrangement 1 80 64 ST7066 "ST7066" Marking : easy to find the PAD (0,0) Chip Size : 2300x3000 Coordinate : Pad Center Origin : Chip Center Pad Size : 90x90 Unit : um 24 41 Subtrate:VDD V1.2 3 2000/6/13 ST7066 Pad Location Coordinates V1.2 Pad No. Function X Y Pad No. Function X Y 1 2 SEG22 SEG21 -1040 -1040 1400 1270 3 SEG20 -1040 1140 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 37 38 39 40 SEG19 SEG18 SEG17 SEG16 SEG15 SEG14 SEG13 SEG12 SEG11 SEG10 SEG9 SEG8 SEG7 SEG6 SEG5 SEG4 SEG3 SEG2 SEG1 GND OSC1 OSC2 V1 V2 V3 V4 V5 CL1 CL2 Vcc M D RS RW E DB0 DB1 -1040 -1040 -1040 -1040 -1040 -1040 -1040 -1040 -1040 -1040 -1040 -1040 -1040 -1040 -1040 -1040 -1040 -1040 -1040 -1040 -1040 -910 -780 -660 -540 -420 -300 -180 -60 60 180 300 420 540 660 780 910 1020 900 780 660 540 420 300 180 60 -60 -180 -300 -420 -540 -660 -780 -900 -1020 -1140 -1270 -1400 -1400 -1400 -1400 -1400 -1400 -1400 -1400 -1400 -1400 -1400 -1400 -1400 -1400 -1400 -1400 -1400 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 73 74 75 76 77 78 79 80 DB2 DB3 DB4 DB5 DB6 DB7 COM1 COM2 COM3 COM4 COM5 COM6 COM7 COM8 COM9 COM10 COM11 COM12 COM13 COM14 COM15 COM16 SEG40 SEG39 SEG38 SEG37 SEG36 SEG35 SEG34 SEG33 SEG32 SEG31 SEG30 SEG29 SEG28 SEG27 SEG26 SEG25 SEG24 SEG23 1040 1040 1040 1040 1040 1040 1040 1040 1040 1040 1040 1040 1040 1040 1040 1040 1040 1040 1040 1040 1040 1040 1040 1040 910 780 660 540 420 300 180 60 -60 -180 -300 -420 -540 -660 -780 -910 -1400 -1270 -1140 -1020 -900 -780 -660 -540 -420 -300 -180 -60 60 180 300 420 540 660 780 900 1020 1140 1270 1400 1400 1400 1400 1400 1400 1400 1400 1400 1400 1400 1400 1400 1400 1400 1400 1400 4 2000/6/13 ST7066 Pin Functions NAME NUMBER I/O INTERFACED WITH RS 1 I MPU R/W 1 I MPU E 1 I MPU DB4 to DB7 4 I/O MPU DB0 to DB3 4 I/O MPU CL1 1 O Extension driver CL2 1 O Extension driver M 1 O Extension driver D 1 O Extension driver COM1 to COM16 16 O LCD SEG1 to SEG40 40 O LCD V1 to V5 5 - Power supply VCC , GND 2 - Power supply OSC1, OSC2 2 Oscillation resistor clock FUNCTION Select registers. 0: Instruction register (for write) Busy flag: address counter (for read) 1: Data register (for write and read) Select read or write. 0: Write 1: Read Starts data read/write. Four high order bi-directional tristate data bus pins. Used for data transfer and receive between the MPU and the ST7066. DB7 can be used as a busy flag. Four low order bi-directional tristate data bus pins. Used for data transfer and receive between the MPU and the ST7066. These pins are not used during 4-bit operation. Clock to latch serial data D sent to the extension driver Clock to shift serial data D Switch signal for converting the liquid crystal drive waveform to AC Character pattern data corresponding to each segment signal Common signals that are not used are changed to non-selection waveform. COM9 to COM16 are non-selection waveforms at 1/8 duty factor and COM12 to COM16 are non-selection waveforms at 1/11 duty factor. Segment signals Power supply for LCD drive VCC - V5 = 11 V (Max) VCC : 2.7V to 5.5V, GND: 0V When crystal oscillation is performed, a resistor must be connected externally. When the pin input is an external clock, it must be input to OSC1. Note: 1. Vcc>=V1>=V2>=V3>=V4>=V5 must be maintained 2. Two clock options: R=91K (Vcc=5V) R=75K OSC1 OSC2 OSC1 OSC2 1 1 1 1 R V1.2 Clock input 5 2000/6/13 ST7066 FUNCTION DESCRIPTION System Interface This chip has all two kinds of interface type with MPU : 4-bit bus and 8-bit bus. 4-bit bus or 8-bit bus is selected by DL bit in the instruction register. During read or write operation, two 8-bit registers are used. One is data register (DR), the other is instruction register(IR). The data register(DR) is used as temporary data storage place for being written into or read from DDRAM/CGRAM, target RAM is selected by RAM address setting instruction. Each internal operation, reading from or writing into RAM, is done automatically. So to speak, after MPU reads DR data, the data in the next DDRAM/CGRAM address is transferred into DR automatically. Also after MPU writes data to DR, the data in DR is transferred into DDRAM/CGRAM automatically. The Instruction register(IR) is used only to store instruction code transferred from MPU. MPU cannot use it to read instruction data. To select register, use RS input pin in 4-bit/8-bit bus mode. Table 1. Various kinds of operations according to RS and R/W bits. RS RW Operation L L Instruction Write operation (MPU writes Instruction code into IR) L H Read Busy Flag(DB7) and address counter (DB0 ~ DB6) H L Data Write operation (MPU writes data into DR) H H Data Read operation (MPU reads data from DR) Busy Flag (BF) When BF = "High”, it indicates that the internal operation is being processed. So during this time the next instruction cannot be accepted. BF can be read, when RS = Low and R/W = High (Read Instruction Operation), through DB7 port. Before executing the next instruction, be sure that BF is not High. Address Counter (AC) Address Counter(AC) stores DDRAM/CGRAM address, transferred from IR. After writing into (reading from) DDRAM/CGRAM, AC is automatically increased (decreased) by 1. When RS = "Low" and R/W = "High", AC can be read through DB0 ~ DB6 ports. V1.2 6 2000/6/13 ST7066 Display Data RAM (DDRAM) Display data RAM (DDRAM) stores display data represented in 8-bit character codes. Its extended capacity is 80 x 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 ST7066, 8 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 4F AC AC6 AC5 AC4 AC3 AC2 AC1 AC0 1 0 0 1 1 1 1 Figure 1 DDRAM Address Display Position 1 (Digit) 00 DDRAM Address 2 3 4 5 6 01 02 03 04 05 ……………….. 78 79 80 4D 4E 4F Figure 2 11-Line Display Display Position 1 2 3 4 5 6 7 8 00 01 02 03 04 05 06 07 For Shift Left 01 02 03 04 05 06 07 08 For Shift Right 4F 00 01 02 03 04 05 06 DDRAM Address Figure 3 11-Line by 88-Character Display Example !" 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 ST7066 is used, 8 characters × 2 lines are displayed. See Figure 5. V1.2 7 2000/6/13 ST7066 When display shift operation is performed, the DDRAM address shifts. See Figure 5. Display Position 1 00 DDRAM Address 40 (hexadecimal) 2 3 4 5 6 01 02 03 04 05 41 42 43 44 45 38 39 40 ……………….. 25 26 27 ……………….. 65 66 67 Figure 4 22-Line Display Display Position DDRAM Address For Shift Left For Shift Right 1 2 3 4 5 6 7 8 00 01 02 03 04 05 06 07 40 41 42 43 44 45 46 47 01 02 03 04 05 06 07 08 41 42 43 44 45 46 47 48 27 00 01 02 03 04 05 06 67 40 41 42 43 44 45 46 Figure 5 22-Line by 88-Character Display Example Case 2: For a 16-character × 2-line display, the ST7066 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 1 2 3 4 5 6 7 8 9 10 11 12 15 16 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F For Shift Left 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F 50 For Shift Right 27 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 67 40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E Position DDRAM Address 13 14 Figure 6 22-Line by 1616-Character Display Example V1.2 8 2000/6/13 ST7066 Character Generator ROM (CGROM) The character generator ROM generates 5 x 8 dot or 5 x 11 dot character patterns from 8-bit character codes. It can generate 208 5 x 8 dot character patterns and 32 5 x 11 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 x 8 dots, eight character patterns can be written, and for 5 x 11 dots, four character patterns can be written. Write into DDRAM the character codes at the addresses shown as the left column of Table 4 to show the character patterns stored in CGRAM. See Table 5 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. 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 interference, such as flickering, in areas other than the display area. LCD Driver Circuit LCD Driver circuit has 16 common and 40 segment signals for LCD driving. Data from CGRAM/CGROM is transferred to 40 bit segment latch serially, and then it is stored to 40 bit shift latch. When each common is selected by 16 bit common register, segment data also output through segment driver from 40 bit segment latch. In case of 1-line display mode, COM1 ~ COM8 have 1/8 duty or COM1 ~ COM11 have 1/11duty , and in 2-line mode, COM1 ~ COM16 have 1/16 duty ratio. Cursor/Blink Control Circuit It can generate the cursor or blink in the cursor/blink control circuit. The cursor or the blink appears in the digit at the display data RAM address set in the address counter. V1.2 9 2000/6/13 ST7066 Table 4 Correspondence between Character Codes and Character Patterns (ROM Code: 0A) V1.2 10 2000/6/13 ST7066 Table 4(Cont.) (ROM Code: 0B) V1.2 11 2000/6/13 ST7066 Character Code (DDRAM Data) b7 b6 b5 b4 b3 b3 b1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 CGRAM Address b0 b5 b4 b3 b2 b1 0 0 0 0 0 0 0 0 1 0 0 1 0 0 0 0 1 0 0 1 0 0 1 1 0 1 1 1 0 0 1 0 0 1 0 1 1 0 1 0 0 0 1 1 0 1 1 0 1 1 1 1 1 1 Character Patterns (CGRAM Data) b0 b7 b6 b5 b4 b3 b2 b1 0 1 1 1 1 1 0 0 1 0 0 0 0 1 0 1 0 0 1 0 - - 0 0 0 1 0 1 0 0 1 0 0 0 0 1 0 1 0 0 0 0 0 1 1 1 1 1 1 0 0 0 0 1 0 0 0 1 1 1 1 1 - - 0 1 0 1 0 1 1 0 0 1 0 1 0 0 0 1 0 0 0 0 b0 1 0 0 0 0 0 0 0 0 1 1 0 0 0 1 0 Table 5 Relationship between CGRAM Addresses, Character Codes (DDRAM) and Character patterns (CGRAM Data) 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). 4. As shown Table 5, 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. V1.2 12 2000/6/13 ST7066 Instructions There are four categories of instructions that: !" Designate ST7066 functions, such as display format, data length, etc. !" Set internal RAM addresses !" Perform data transfer with internal RAM !" Others Instruction Table: Instruction Code Instruction RS RW Clear Display 0 0 Description Description DB DB DB DB DB DB DB DB 7 6 5 4 3 2 1 0 0 0 0 0 0 0 0 1 Time (270KHZ) Write "20H" to DDRAM. and set DDRAM address to "00H" from AC 1.52 ms Set DDRAM address to "00H" from AC Return Home 0 0 0 0 0 0 0 0 1 x and return cursor to its original position if shifted. The contents of DDRAM are 1.52 ms not changed. Sets cursor move direction and Entry Mode Set 0 0 0 0 0 0 0 1 I/D S specifies display shift. These operations are performed during data write and 37 us read. Display ON/OFF D=1: entire display on 0 0 0 0 0 0 1 D C B C=1: cursor on Cursor or Display Set cursor moving and display shift 0 0 0 0 0 1 S/C R/L x x Shift Function Set address 0 0 0 0 0 0 0 0 1 to RAM Read data from RAM DL N F x x NL: number of line is 2/1 37 us 1 AC AC AC AC AC AC 5 4 3 2 1 Set CGRAM address in address counter 37 us 0 AC AC AC AC AC AC AC Set DDRAM address in address counter 6 5 4 3 2 1 0 37 us Whether during internal operation or not 0 1 address Write data 1 F: font size is 5x11/5x8 Read Busy flag and 37 us DL: interface data is 8/4 bits 0 address Set DDRAM control bit, and the direction, without changing DDRAM data. Set CGRAM 37 us B=1: cursor position on BF AC AC AC AC AC AC AC can be known by reading BF. The 6 5 4 3 2 1 0 contents of address counter can also be 0 us read. 1 0 D7 D6 D5 D4 D3 D2 D1 D0 1 1 D7 D6 D5 D4 D3 D2 D1 D0 Write data into internal RAM (DDRAM/CGRAM) Read data from internal RAM (DDRAM/CGRAM) 43 us 43 us Note: Be sure the ST7066 is not in the busy state (BF = 0) before sending an instruction from the MPU to the ST7066. 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 Instruction Table for the list of each instruction execution time. V1.2 13 2000/6/13 ST7066 INSTRUCTION DESCRIPTION !" Clear Display RS Code 0 RW DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 0 0 0 0 0 0 0 0 1 Clear all the display data by writing "20H" (space code) to all DDRAM address, and set DDRAM address to "00H" into AC (address counter). Return cursor to the original status, namely, bring the cursor to the left edge on first line of the display. Make entry mode increment (I/D = "1"). !" Return Home RS Code 0 RW DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 0 0 0 0 0 0 0 1 x Return Home is cursor return home instruction. Set DDRAM address to "00H" into the address counter. Return cursor to its original site and return display to its original status, if shifted. Contents of DDRAM does not change. !" Entry Mode Set RS Code 0 RW DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 0 0 0 0 0 0 1 I/D S Set the moving direction of cursor and display. I/D : Increment / decrement of DDRAM address (cursor or blink) When I/D = "High", cursor/blink moves to right and DDRAM address is increased by 1. When I/D = "Low", cursor/blink moves to left and DDRAM address is decreased by 1. * CGRAM operates the same as DDRAM, when read from or write to CGRAM. S: Shift of entire display When DDRAM read (CGRAM read/write) operation or S = "Low", shift of entire display is not performed. If S = "High" and DDRAM write operation, shift of entire display is performed according to I/D value (I/D = "1" : shift left, I/D = "0" : shift right). V1.2 S I/D DESCRIPTION H H Shift the display to the left H L Shift the display to the right 14 2000/6/13 ST7066 !" Display ON/OFF RS Code RW DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 0 0 0 0 0 0 1 D C B Control display/cursor/blink ON/OFF 1 bit register. D : Display ON/OFF control bit When D = "High", entire display is turned on. When D = "Low", display is turned off, but display data is remained in DDRAM. C : Cursor ON/OFF control bit When C = "High", cursor is turned on. When C = "Low", cursor is disappeared in current display, but I/D register remains its data. B : Cursor Blink ON/OFF control bit When B = "High", cursor blink is on, that performs alternate between all the high data and display character at the cursor position. When B = "Low", blink is off. !" Cursor or Display Shift RS Code 0 RW DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 0 0 0 0 1 S/C R/L x x Without writing or reading of display data, shift right/left cursor position or display. This instruction is used to correct or search display data. During 2-line mode display, cursor moves to the 2nd line after 40th digit of 1st line. Note that display shift is performed simultaneously in all the line. When displayed data is shifted repeatedly, each line shifted individually. When display shift is performed, the contents of address counter are not changed. S/C R/L L L Shift cursor to the left AC=AC-1 L H Shift cursor to the right AC=AC+1 H L Shift display to the left. Cursor follows the display shift AC=AC H H Shift display to the right. Cursor follows the display shift AC=AC !" Function Set Description RS Code 0 AC Value RW DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 0 0 0 1 DL N F x x Control display/cursor/blink ON/OFF 1 bit register. V1.2 15 2000/6/13 ST7066 DL : Interface data length control bit When DL = "High", it means 8-bit bus mode with MPU. When DL = "Low", it means 4-bit bus mode with MPU. So to speak, DL is a signal to select 8-bit or 4-bit bus mode. When 4-bit bus mode, it needs to transfer 4-bit data by two times. N : Display line number control bit When N = "Low", it means 1-line display mode. When N = "High", 2-line display mode is set. F : Display font type control bit When F = "Low", it means 5 x 8 dots format display mode When F = "High", 5 x11 dots format display mode. N F L L L H No. of Display Character Font Duty Factor 1 5x8 1/8 H 1 5x11 1/11 x 2 5x8 1/16 Lines !" Set CGRAM Address Code RS RW 0 0 DB7 0 DB6 1 DB5 DB4 DB3 DB2 DB1 DB0 AC5 AC4 AC3 AC2 AC1 AC0 Set CGRAM address to AC. This instruction makes CGRAM data available from MPU. !" Set DDRAM Address Code RS RW 0 0 DB7 1 DB6 DB5 DB4 DB3 DB2 DB1 DB0 AC6 AC5 AC4 AC3 AC2 AC1 AC0 Set DDRAM address to AC. This instruction makes DDRAM data available from MPU. When 1-line display mode (N = 0), DDRAM address is from "00H" to "4FH". In 2-line display mode (N = 1), DDRAM address in the 1st line is from "00H" to "27H", and DDRAM address in the 2nd line is from "40H" to "67H". V1.2 16 2000/6/13 ST7066 !" Read Busy Flag and Address Code RS RW DB7 0 1 BF DB6 DB5 DB4 DB3 DB2 DB1 DB0 AC6 AC5 AC4 AC3 AC2 AC1 AC0 When BF = “High”, indicates that the internal operation is being processed.So during this time the next instruction cannot be accepted. The address Counter (AC) stores DDRAM/CGRAM addresses, transferred from IR. After writing into (reading from) DDRAM/CGRAM, AC is automatically increased (decreased) by 1. !" Write Data to CGRAM or DDRAM RS Code 1 RW DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 0 D7 D6 D5 D4 D3 D2 D1 D0 Write binary 8-bit data to DDRAM/CGRAM. The selection of RAM from DDRAM, CGRAM, is set by the previous address set instruction : DDRAM address set, CGRAM address set. RAM set instruction can also determine the AC direction to RAM. After write operation, the address is automatically increased/decreased by 1, according to the entry mode. !" Read Data from CGRAM or DDRAM RS Code 1 RW DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 1 D7 D6 D5 D4 D3 D2 D1 D0 Read binary 8-bit data from DDRAM/CGRAM. The selection of RAM is set by the previous address set instruction. If address set instruction of RAM is not performed before this instruction, the data that read first is invalid, because the direction of AC is not determined. If you read RAM data several times without RAM address set instruction before read operation, you can get correct RAM data from the second, but the first data would be incorrect, because there is no time margin to transfer RAM data. In case of DDRAM read operation, cursor shift instruction plays the same role as DDRAM address set instruction : it also transfer RAM data to output data register. After read operation address counter is automatically increased/decreased by 1 according to the entry mode. After CGRAM read operation, display shift may not be executed correctly. * In case of RAM write operation, after this AC is increased/decreased by 1 like read operation. In this time, AC indicates the next address position, but you can read only the previous data by read instruction. V1.2 17 2000/6/13 ST7066 Reset Function Initializing by Internal Reset Circuit An internal reset circuit automatically initializes the ST7066 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 10 ms after VCC rises to 4.5 V. 1. Display clear 2. Function set: DL = 1; 8-bit interface data N = 0; 1-line display F = 0; 5 ´ 8 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 ST7066. For such a case, initialization must be performed by the MPU as explain by the following figure. V1.2 18 2000/6/13 ST7066 8-bit Interface: Power On Wait time > 15ms After Vcc > 4.5V RS RW D7 D6 D5 D4 D3 D2 D1 D0 BF cannot be checked before the Instruction Function set 0 0 0 0 1 1 x x x x Wait time > 4.1ms BF cannot be checked before the Instruction Function set 0 0 0 0 1 1 x x x x Wait time > 100us BF cannot be checked before the Instruction Function set 0 0 0 0 1 1 x x x x BF can be checked after the following Instructions Function Set 0 0 0 0 1 1 N F x x 0 0 0 0 0 0 1 0 0 0 Display Off 0 0 0 0 0 0 0 0 0 1 Display Clear 0 0 0 0 0 0 0 1 I/D S Entry mode set Initialization End V1.2 19 2000/6/13 ST7066 4-bit Interface: Power On Wait time > 15ms After Vcc > 4.5V RS RW D7 D6 D5 D4 0 0 0 0 1 BF cannot be checked before the Instruction Function set 1 Wait time > 4.1ms 0 0 0 0 1 BF cannot be checked before the Instruction Function set 1 Wait time > 100us BF cannot be checked before the Instruction Function set 0 0 0 0 1 1 0 0 0 0 1 0 BF can be checked after the following Instructions 0 0 0 0 1 0 0 0 0 N 0 F Function Set 0 0 0 0 0 1 0 0 0 0 0 0 Display Off 0 0 0 0 0 0 0 0 0 0 0 1 Display Clear 0 0 0 0 0 0 0 0 0 1 I/D S Entry mode set Initialization End V1.2 20 2000/6/13 ST7066 Interfacing to the MPU The ST7066 can send data in either two 4-bit operations or one 8-bit operation, thus allowing interfacing with 4- or 8-bit MPU. !" 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 ST7066 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. Supply Voltage for LCD Drive There are different voltages that supply to ST7066’s pin (V1 - V5) to obtain LCD drive waveform. The relations of the bias, duty factor and supply voltages are shown as below: Duty Factor 1/8, 1/11 1/16 Bias Supply Voltage 1/4 1/5 V1 Vcc - 1/4VLCD Vcc - 1/5VLCD V2 Vcc - 1/2VLCD Vcc - 2/5VLCD V3 Vcc - 1/2VLCD Vcc - 3/5VLCD V4 Vcc - 3/4VLCD Vcc - 4/5VLCD V5 Vcc - VLCD Vcc- VLCD 1/5 bias (1/16 duty cycle) 1/4 bias (1/8, 1/11 duty cycle) V5 -5V VR V4 R V3 R V2 V1 R Vcc R Vcc +5V R VLCD V1.2 V1 V2 R V3 R V4 R V5 R VR -5V VLCD 21 2000/6/13 ST7066 Timing Characteristics !" Writing data from MPU to ST7066 RS R/W VIH1 VIL1 TAH TAS TAH TPW E TDSW TR TH Valid data DB0-DB7 TC !" Reading data from ST7066 to MPU RS VIH1 VIL1 TAS TAH R/W TR TAH TPW E TDDR DB0-DB7 TH Valid data TC V1.2 22 2000/6/13 ST7066 Absolute Maximum Ratings Characteristics Symbol Value Power Supply Voltage VCC -0.3V to +7.0V LCD Driver Voltage VLCD -0.3V to +13.0V Input Voltage VIN -0.3V to VCC+0.3V Operating Temperature TA -20 C to +70 C Storage Temperature TSTO -55 C to +125 C o o o o o DC Characteristics (TA = 25 C, VCC = 2.7V - 5.5V) Symbol Characteristics Test Condition Min. Typ. Max. Unit VCC Operating Voltage - 2.7 - 5.5 V VLCD LCD Voltage VCC-V5 3.0 - 11 V - 0.3 0.6 mA - 2.2 - VCC V - -0.3 - 0.6 V - VCC-1 - VCC V - - - 1.0 V IOH = -0.1mA 2.4 - VCC V IOL = 0.1mA - - 0.4 V IOH = -0.04mA 0.9VCC - VCC V IOL = 0.04mA - - 0.1VCC V ICC VIH1 Power Supply Current fOSC = 270KHz, VCC=5V Input High Voltage (Except OSC1) VIL1 Input Low Voltage (Except OSC1) VIH2 Input High Voltage (OSC1) VIL2 Input Low Voltage (OSC2) VOH1 Output High Voltage (DB0 - DB7) VOL1 Output Low Voltage (DB0 - DB7) VOH2 Output High Voltage (Except DB0 - DB7) VOL2 Output Low Voltage (Except DB0 - DB7) RCOM Common Resistance VLCD = 4V, Id = 0.05mA - 2 20 KΩ RSEG Segment Resistance VLCD = 4V, Id = 0.05mA - 2 30 KΩ ILEAK Input Leakage VIN = 0V to VCC -1 - 1 µA VCC = 5V 10 50 120 µA Current IPUP V1.2 Pull Up MOS Current 23 2000/6/13 ST7066 o AC Characteristics (TA = 25 C, VCC = 5V) Symbol Characteristics Test Condition Min. Typ. Max. Unit Internal Clock Operation fOSC OSC Frequency R = 91KΩ 190 270 350 KHz 125 250 350 KHz External Clock Operation fEX TR,TF External Frequency Duty Cycle - 45 50 55 % Rise/Fall Time - - - 0.2 µs Write Mode (Writing data from MPU to ST7066) TC Enable Cycle Time Pin E 400 - - ns TPW Enable Pulse Width Pin E 150 - - ns TR,TF Enable Rise/Fall Time Pin E - - 25 ns TAS Address Setup Time Pins: RS,RW,E 30 - - ns TAH Address Hold Time Pins: RS,RW,E 10 - - ns TDSW Data Setup Time Pins: DB0 - DB7 40 - - ns TH Data Hold Time Pins: DB0 - DB7 10 - - ns Read Mode (Reading Data from ST7066 to MPU) TC Enable Cycle Time Pin E 400 - - ns TPW Enable Pulse Width Pin E 150 - - ns TR,TF Enable Rise/Fall Time Pin E - - 25 ns TAS Address Setup Time Pins: RS,RW,E 30 - - ns TAH Address Hold Time Pins: RS,RW,E 10 - - ns TDDR Data Setup Time Pins: DB0 - DB7 - - 100 ns TH Data Hold Time Pins: DB0 - DB7 10 - - ns Interface Mode with LCD Driver(ST7065) V1.2 TCWH Clock Pulse with High Pins: CL1, CL2 800 - - ns TCWL Clock Pulse with Low Pins: CL1, CL2 800 - - ns TCST Clock Setup Time Pins: CL1, CL2 500 - - ns TSU Data Setup Time Pin: D 300 - - ns TDH Data Hold Time Pin: D 300 - - ns TDM M Delay Time Pin: M -1000 - 1000 ns 24 2000/6/13 ST7066 The relations between Oscillation Frequency and LCD Frame Frequency Assume the oscillation frequency is 270KHZ, 1 clock cycle time = 3.7us 1. 1/8 Duty 400 clocks 1 2 3 ------ 4 8 1 2 Vcc COM1 V1 V2(V3) V4 V5 1 frame 1 frame = 3.7(us) x 400 x 8 = 11850(us) = 11.9(ms) 2. 1/11 Duty 400 clocks 1 COM1 2 3 4 ------ 11 1 2 Vcc V1 V2(V3) V4 V5 1 frame 1 frame = 3.7(us) x 400 x 11 = 16300(us) = 16.3(ms) 3. 1/16 Duty 200 clocks 1 COM1 2 3 4 ------ 16 1 2 Vcc V1 V2 V3 V4 V5 1 frame 1 frame = 3.7(us) x 200 x 16 = 11850(us) = 11.9(ms) V1.2 25 2000/6/13 ST7066 I/O PAD Configuration Input PAD: E (No Pull-up) Input PAD: RS, RW(with Pull-up) Output PAD: CL1, CL2, M, D Enable DATA I/O PAD: DB0 – DB7 V1.2 26 2000/6/13 ST7066 LCD and ST7066 Connection 1. 5x8 dots, 8 characters x 1 line (1/4 bias, 1/8 duty) ST7066 COM1 . . . . . COM8 SEG1 . . . SEG40 LCD Panel: 8 Characters x 1 line ST7066 2. 5x11 dots, 8 characters x 1 line (1/4 bias, 1/11 duty) COM1 . . . . . . . . COM11 LCD Panel: 8 Characters x 1 line SEG1 . . . . . . . SEG40 V1.2 27 2000/6/13 ST7066 3. 5x8 dots, 8 characters x 2 line (1/5 bias, 1/16 duty) ST7066 COM1 . . . . . COM8 COM9 . . . . . COM16 LCD Panel: 8 Characters x 2 line SEG1 . . . . . . . SEG40 4. 5x8 dots, 16 characters x 1 line (1/5 bias, 1/16 duty) ST7066 COM1 . . . . . COM8 SEG1 . . . . SEG40 LCD Panel: 16 Characters x 1 line COM9 . . . . . COM16 V1.2 28 2000/6/13 ST7066 ST7066 Application circuit COM1-16 D SEG1-40 ST7066 VCC GND CL2 CL1 M V1 V2 V3 V4 V5 Vcc(+5V ) Y1-Y40 V3 V4 ST7065 V2 Reg. DR2 DL2 DR1 CL1 CL2 M V6 Reg. V5 Dot Matrix LCD Panel DL1 VDD FCS SHL1 SHL2 GND VEE V1 Reg. Reg. DL1 VDD FCS SHL1 SHL2 GND VEE V1 Reg. Y1-Y40 V3 V4 ST7065 V2 Reg. V5 DR2 DL2 DR1 CL1 CL2 M V6 -V or GND 2000/6/13 29 V1.2 DB0-DB7 To MPU Note: R= 2.2K ~ 10K, VR= 10K~30K