Specifications

WA_DEV_FEX20_PTS_004 Rev 001 June 30, 2010 24
Expansion Card Product Technical
Specification
Interfaces
4.4. Serial Interface
The Expansion Card may be connected to an LCD driver through either of the two SPI bus interface.
4.4.1. SPI Bus
Both SPI bus interface includes:
 a CLK signal
 an I/O signal
 an I signal
 a CS signal complying with the standard SPI bus
4.4.1.1. Characteristics
The following lists the features available on the SPI bus:
 Master mode operation
 SPI speed is from 101.5 Kbit/s to 13 Mbit/s in master mode operation
 3 or 4-wire interface
 SPI-mode configuration: 0 to 3
 1 to 16 bits data length
4.4.1.2. Configuration
Table 12: SPI Bus Configuration
Operation
Maximum Speed
SPI-Mode
Duplex
3-wire Type
4-wire Type
Master
13 Mb/s
0,1,2,3
Half
SPIx-CLK; SPIx-IO;
~SPIx-CS
SPIx-CLK; SPIx-IO;
SPIx-I; ~SPIx-CS
Note that for the 4-wire configuration, SPIx-I/O is used as output only; and SPIx-I is used as input
only. For the 3-wire configuration, SPIx-I/O is used as both input and output.
4.4.1.3. Pin Description
Refer to the following tables for the pin description of both SPI bus interface.
Table 13: SPI1 Bus Pin Description
Pin
Number
Signal
I/O
I/O Type
Reset State
Description
Multiplexed
With
16
SPI1-CLK
O
2V8
Z
SPI Serial Clock
GPIO28
18
SPI1-IO
I/O
2V8
Z
SPI Serial input/output
GPIO29
17
SPI1-I
I
2V8
Z
SPI Serial input
GPIO30
15
~SPI1-CS
O
2V8
Z
SPI Enable
GPIO31
Refer to section 4.2 Electrical Information for Digital I/O for open drain, 2V8 and 1V8 voltage
characteristics and reset state definitions.