MCIMX31C Datasheet, PDF (72/110 Pages) Freescale Semiconductor, Inc – Multimedia Applications Processors for Industrial and Automotive Products

Electrical Characteristics
The DISP#_IF_CLK_PER_WR, DISP#_IF_CLK_PER_RD, HSP_CLK_PERIOD,
DISP#_IF_CLK_DOWN_WR, DISP#_IF_CLK_UP_WR, DISP#_IF_CLK_DOWN_RD,
DISP#_IF_CLK_UP_RD and DISP#_READ_EN parameters are programmed via the
DI_DISP#_TIME_CONF_1, DI_DISP#_TIME_CONF_2 and DI_HSP_CLK_PER Registers.
4.3.15.5.3 Serial Interfaces, Functional Description
The IPU supports the following types of asynchronous serial interfaces:
• 3-wire (with bidirectional data line)
• 4-wire (with separate data input and output lines)
• 5-wire type 1 (with sampling RS by the serial clock)
• 5-wire type 2 (with sampling RS by the chip select signal)
Figure 60 depicts timing of the 3-wire serial interface. The timing images correspond to active-low
DISPB_D#_CS signal and the straight polarity of the DISPB_SD_D_CLK signal.
For this interface, a bidirectional data line is used outside the device. The IPU still uses separate input and
output data lines (IPP_IND_DISPB_SD_D and IPP_DO_DISPB_SD_D). The I/O mux should provide
joining the internal data lines to the bidirectional external line according to the IPP_OBE_DISPB_SD_D
signal provided by the IPU.
Each data transfer can be preceded by an optional preamble with programmable length and contents. The
preamble is followed by read/write (RW) and address (RS) bits. The order of the these bits is
programmable. The RW bit can be disabled. The following data can consist of one word or of a whole
burst. The interface parameters are controlled by the DI_SER_DISP1_CONF and DI_SER_DISP2_CONF
Registers.
DISPB_D#_CS
1 display IF
clock cycle
1 display IF
clock cycle
DISPB_SD_D_CLK
DISPB_SD_D
RW RS D7 D6 D5 D4 D3 D2 D1 D0
Preamble
Input or output data
Figure 60. 3-Wire Serial Interface Timing Diagram
Figure 61 depicts timing of the 4-wire serial interface. For this interface, there are separate input and output
data lines both inside and outside the device.
MCIMX31C/MCIMX31LC Technical Data, Rev. 4
72
Freescale Semiconductor