SSD1805TR1 ETC2 [List of Unclassifed Manufacturers], SSD1805TR1 Datasheet - Page 30

• Manufacturer Part Number: SSD1805TR1
• Description: 132 x 68 STN LCD Segment / Common Monochrome Driver with Controller
• Manufacturer: ETC2 [List of Unclassifed Manufacturers]

9.16 Set Read-Modify-Write Mode
This command puts the chip in read-modify-write mode in which:
1. Column address is saved before entering the mode
2. Column address is increased only after display data write but not after display data read.
This Read-Modify-Write mode is used to save the MCU’s loading when a very portion of display area is being
updated frequently. As reading the data will not change the column address, it could be get back from the
chip and do some operation in the MCU. Then the updated data could be written back to the GDDRAM with
automatic address increment. After updating the area, “Set End of Read-Modify-Write Mode” is sent to restore
the column address and ready for next update sequence.
9.17 Software Reset
Issuing this command causes some of the chip’s internal status registers to be initialized:
Read-Modify-Write mode is off
Static indicator is turned OFF
Display start line register is cleared to 0
Column address counter is cleared to 0
Page address is cleared to 0
Normal scan direction of the COM outputs
Internal gain resistors Ratio is set to 4
Contrast control register is set to 20h
9.18 Set End of Read-Modify-Write Mode
This command relieves the chip from read-modify-write mode. The column address before entering read-
modify-write mode will be restored no matter how much modification during the read-modify-write mode.
9.19 Set Indicator On/Off
This command turns on or off the static indicator driven by the M and MSTAT pins.
When the “Set Indicator On” command is sent, the second command byte “Indicator Display Mode” must be
followed. However, the “Set Indicator Off” command is a single byte command and no second byte command
is required.
The status of static indicator also controls whether standby mode or sleep mode will be entered, after issuing
the power save compound command. See “Set Power Save Mode” later in this section.
9.20 NOP
A command causing the chip takes No Operation.
9.21 Set Test Mode
This command forces the driver chip into its test mode for internal testing of the chip. Under normal operation,
users should NOT use this command.
9.22 Set Power Save Mode
Entering Standby or Sleep Mode should be done by using a compound command composed of “Set Display
ON/OFF” and “Set Entire Display ON/OFF” commands. When “Set Entire Display ON” is issued when display
is OFF, either Standby Mode or Sleep Mode will be entered. The status of the Static Indicator will determine
which power save mode is entered. If static indicator is off, the Sleep Mode will be entered:
Internal oscillator and LCD power supply circuits are stopped
Segment and Common drivers output V
level
SS
The display data and operation mode before sleep are held
Internal display RAM can still be accessed
If the static indicator is on, the chip enters Standby Mode that is similar to sleep mode except addition with:
Internal oscillator is on
Static drive system is on
Please also be noted that during Standby Mode, if the software reset command is issued, Sleep Mode will be
entered. Both power save modes can be exited by the issue of a new software command or by pulling Low at
hardware pin
.
RES
Solomon Systech
Jun 2004 P 30/52
Rev 1.1
SSD1805 Series