Samsung S5PC100, User Manual

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S5PC100 USER’S MANUAL (REV1.0) SPI CONTROLLER
8.3-3
2.1.4 Packet Number Control
SPI controls the number of packets to be received in master mode. Set SFR (Packet_Count_reg) to receive any
number of packets. SPI stops generating SPICLK if the number of packets is the same as what you had set. It is
mandatory to follow software or hardware reset before this function is reloaded. (Software reset can clear all
registers except special function registers, but hardware reset clears all registers.)
2.1.5 Chip Select Control
Chip select XspiCS is active low signal. In other words, a chip is selected when XspiCS input is 0.
XspiCS# can be selected auto control or manual control.
When you use manual control mode, AUTO_N_MANUAL must be cleared (Default value is 0). XspiCS# level is
controlled by NSSOUT bit.
When you use audio control mode, AUTO_N_MANUAL must be set. XspiCS toggled between packet and packet
automatically. Inactive period of XspiCS is controlled by NCS_TIME_COUNT. NSSOUT is not available at this
time.
2.1.6 CLOCK CONTROL
Each SPI get three different clocks from Clock Controller. User can select one of them to make SPI clock by
setting CLK_CFG register.
PCLK
SCLK_SPI0_48
SCLK_SPI0
SPICLK0
2
0
1
PCLK
SCLK_SPI1_48
SCLK_SPI1
SPICLK1
2
0
1
PCLK
SCLK_SPI2_48
SCLK_SPI2
SPICLK2
2
0
1
SPI0
SPI1
SPI2
Clock
Controller
Figure 8.3-1 SPI CLOCK