4D systems Picaso, Datasheet, Page: 9 / 28

Picaso Processor Datasheet
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2017 4D Labs Semiconductors Page 9 of 27
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5. Pin Description
The Picaso Processor provides both a hardware and a
software interface. This section describes in detail the
hardware interface pins of the device.
5.1. Display Interface
The Picaso supports LCD and OLED displays with an 80-
Series 16-bit wide CPU data interface. The connectivity
to the display is easy and straight forward. The Picaso
generates all of the necessary timing to drive the
display.
CS RS RD WR Operation
0 0 0 1 Read Display Status Register
0 0 1 0 Write Display Index Register
0 1 0 1 Read Display GRAM Data
0 1 1 0 Write Register or GRAM Data
1 X X X No Operation
Display Operation Table
D0-D15 pins (Display Data Bus):
The Display Data Bus (D0-D15) is a 16-bit bidirectional
port and all display data writes and reads occur over
this bus. Other control signals such as RW, RD CS, and
RS synchronise the data transfer to and from the
display.
CS pin (Display Chip Select):
The access to the display is only possible when the
Display Chip Select (CS) is asserted LOW. Connect this
pin to the Chip Select (CS) signal of the display.
RS pin (Display Register Select):
The RS signal determines whether a register command
or data is sent to the display.
LOW: Display index or status register is selected.
HIGH: Display GRAM or register data is selected.
Connect this pin to the Register Select (RS) signal of
the display. Different displays utilise various naming
conventions such as RS, A0, C/D or similar. Be sure to
check with your display manufacturer for the correct
name and function.
RES pin (Display Reset):
Display RESET. Picaso initialises the display by strobing
this pin LOW. Connect this pin to the Reset (RES) signal
of the display.
DCENB pin (External DC/DC Enable):
DC-DC high voltage enable signal. This maybe the high
voltage that drives the LCD backlight or the OLED
panel supply.
WR pin (Display Write):
This is the display write strobe signal. The Picaso
asserts this signal LOW when writing data to the
display in conjunction with the display data bus (D0-
D15). Connect this pin to the Write (WR) signal of the
display.
Item Sym Min Typ Max
Write Low Pulse tWL 50 - -
Write High Pulse tWH 50 - -
Write Bus Cycle Total tWT 100 - -
Write Data Setup tDS 25 - -