PDF《LED Driver IC》

4 display mode settings as shown in the diagram below: As stated earlier a command is the first one byte (b0 to b7) transmitted to PT6965 via the DIN Pin when STB is LOW. However, for these commands, the bit

3 &

bit

8 (b2 to b7) are given a value of 0. The Display Mode Setting Commands determine the number of segments and grids to be used (14 to

11 segments,

4 to

7 grids). A display command ON must be executed in order to resume display. If the same mode setting is selected, no command execution is take place, therefore, nothing happens. When Power is turned ON, the 7-grid, 11-segment modes is selected. MSB LSB

0 0

0 0

0 0 b1 b0 Display Mode Settings: 00:

4 digits,

14 segments 01:

5 digits,

13 segments 10:

6 digits,

12 segments 11:

7 digits,

11 segments COMMANDS 2: DATA SETTING COMMANDS The Data Setting Commands executes the Data Write or Data Read Modes for PT6965. The data Setting Command, the bits

5 and

6 (b4, b5) are given the value of 0, bit

7 (b6) is given the value of

1 while bit

8 (b7) is given the value of 0. Please refer to the diagram below. When power is turned ON, bit

4 to bit

1 (b3 to b0) are given the value of 0. MSB LSB

0 1

0 0 b3 b2 b1 b0 Data Write &

Read Mode Settings: 00: Write Data to Display Mode 10: Read Key Data Address Increment Mode Settings (Display Mode): 0: Increment Address after Data has been written 1: Fixed Address Mode Settings: 0: Normal Operation Mode 1: Test Mode PT6965 V1.5

6 November

2012 PT6965 KEY MATRIX &

KEY INPUT DATA STORAGE RAM PT6965 Key Matrix consists of

10 x

2 array as shown below: Each data entered by each key is stored as follows and read by a READ Command, starting from the last significant bit. When the most significant bit of the data (b0) has been read, the least significant bit of the next data (b7) is read. K1…………………K2 K1…………………K2 SG1/KS1 x SG2/KS2 x x Reading Sequence SG3/KS3 x SG4/KS4 x x SG5/KS5 x SG6/KS6 x x SG7/KS7 x SG8/KS8 x x SG9/KS9 x SG10/KS10 x x b0………………….b1 b2 b3………………….b4 b5 b6………………….b7 Note: b2, b5, b6 and b7 do not care. K1 K2 SG1/ KS1 SG 2/K S2 SG3/ KS3 SG 4/K S4 SG5/KS5 SG6/ KS6 SG7/ KS7 SG8/KS8 SG9/KS9 SG10/KS10 PT6965 V1.5

7 November

2012 COMMANDS 3: ADDRESS SETTING COMMANDS Address Setting Commands are used to set the address of the display memory. The address is considered valid if it has a value of 00H to 0DH. If the address is set to 0EH or higher, the data is ignored until a valid address is set. When power is turned ON, the address is set at 00H. Please refer to the diagram below. MSB LSB

1 1

0 0 b3 b2 b1 b0 Address: 00H to 0DH DISPLAY MODE AND RAM ADDRESS Data transmitted from an external device to PT6965 via the serial interface are stored in the Display RAM and are assigned addresses. The RAM addresses of PT6965 are given below in

8 bits unit. SG1 SG4 SG5 SG8 SG9 SG12 SG13 SG14 00HL 00HU 01HL 01HU DIG1 02HL 02HU 03HL 03HU DIG2 04HL 04HU 05HL 05HU DIG3 06HL 06HU 07HL 07HU DIG4 08HL 08HU 09HL 09HU DIG5 0AHL 0AHU 0BHL 0BHU DIG6 0CHL 0CHU 0DHL 0DHU DIG7 b0 b3 b4 b7 xxHL xxHU Lower

4 bits Higher

4 bits PT6965 V1.5

8 November

2012 COMMAND 4: DISPLAY CONTROL COMMANDS The Display Control Commands are used to turn ON or OFF a display. It also used to set the pulse width. Please refer to the diagram below. When the power is turned ON, a 1/16 pulse width is selected and the displayed is turned OFF (the key scanning is started). MSB LSB

1 0

0 0 b3 b2 b1 b0 Dimming Quantity Settings: 000: Pulse width = 1/16 001: Pulse width = 2/16 010: Pulse width = 4/16 011: Pulse width = 10/16 100: Pulse width = 11/16 101: Pulse width = 12/16 110: Pulse width = 13/16 111: Pulse width = 14/16 Display Settings: 0: Display Off (Key Scan Continues) 1: Display On PT6965 V1.5