S3C24A0A Datasheet, PDF(260/519 Page) Samsung semiconductor – 32-BIT RISC MICROPROCESSOR

English

English German Russian Spanish Italian Polish Chinese Japanese Korean French Portuguese	Language :

S3C24A0A Datasheet, PDF (260/519 Pages) Samsung semiconductor – 32-BIT RISC MICROPROCESSOR

◁

S3C24A0A RISC MICROPROCESSOR (Preliminary Spec)

SPI INTERFACE

SPI OPERATION

Using the SPI interface, 8-bit data can be sending and receiving data simultaneously with an external device. A

serial clock line synchronizes shifting and sampling of the information on the two serial data lines. When SPI is the

master, transmission frequency can be controlled by setting the appropriate bit to SPPREn register. You can

modify its frequency to adjust the baud rate data register value. When SPI is a slave, other master supplies the

clock. When a programmer writes byte data to SPTDATn register, SPI transmit and receive operation will start

simultaneously. In some cases, nSS should be activated before writing byte data to SPTDATn.

Programming Procedure

When a byte data is written into the SPTDATn register, SPI starts to transmit if ENSCK and MSTR of SPCONn

register are set. There is a typical programming procedure to operate an SPI card.

To program the SPI modules, follow these basic steps :

1. Set Baud Rate Prescaler Register (SPPREn)

2. Set SPCONn to configure properly the SPI module

3. Write data 0xFF to SPTDATn 10 times in order to initialize MMC or SD card

4. Set a GPIO pin, which acts as nSS, to low to activate the MMC or SD card.

5. Tx data â Check the status of Transfer Ready flag (REDY=1), and then write data to SPTDATn.

6. Rx data(1) : SPCONn's TAGD bit disable = normal mode

â write 0xFF to SPTDATn, then confirm REDY to set, and then read data from Read Buffer

7. Rx data(2) : SPCONn's TAGD bit enable = Tx Auto Garbage Data mode

â confirm REDY to set, and then read data from Read Buffer(then automatically start to transfer)

8. Set a GPIO pin, which acts as nSS, to high, to deactivate MMC or SD card.

Preliminary product information describe products that are in development,

for which full characterization data and associated errata are not yet available.

Specifications and information herein are subject to change without notice.

15-3

▷