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are trademarks of their respective owners.

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DSPI_FIFO allows direct interface to almost

any existing synchronous serial peripheral.

SPI Controller

manages the Master/Slave

operation and controls the transmission. The

SPI Controller manages the transmission

speed and format (Phase and polarity). Con-

troller is also responsible for generating of

interrupt request and detection of transmission

errors.

PERFORMANCE

The following table gives a survey about

the Core performance in the ALTERA® de-

vices after Place & Route (all key features

have been included):

Device

Speed

grade

Logic Cells

CYCLONE

-6

324

171 MHz

CYCLONE2

-6

314

197 MHz

STRATIX

-5

324

206 MHz

STRATIX2

-3

273

313 MHz

STRATIXGX

-5

324

210 MHz

APEX2A

-7

370

178 MHz

APEX20KC

-7

369

152 MHz

APEX20KE

-1

369

115 MHz

APEX20K

-1

369

94 MHz

ACEX1K

-1

369

103 MHz

FLEX10KE

-1

369

103 MHz

Core performance in ALTERA® devices

Transfer Formats

Software can select any of four combinations of serial clock (SCK) phase and polarity using two

bits in the SPI control register (SPCR). The clock polarity is specified by the CPOL control bit,

which selects an active high or active low clock and has no significant effect on the transfer format.

The clock phase (CPHA) control bit selects one of two fundamentally different transfer formats.

The clock phase and polarity should be identical for the master SPI device and the communicating

slave device. In some cases, the phase and polarity are changed between transfers to allow a

master device to communicate with peripheral slaves having different requirements. The flexibility

of the SPI system on the DSPI_FIFO allows direct interface to almost any existing synchronous

serial peripheral.

6

6

5

5

4

4

3

3

2

21

1LSB

MSB

MSB

LSB

1

2

3

45

67

8

SC K CYC LE#

SC K (C PO L =0)

SC K (C PO L=1)

MO SI

MISO

SS

6

6

5

5

4

4

3

3

2

21

1LSB

MSB

MSB

LSB

1

2

3

45

67

8

SC K CY CLE #

SC K (C P O L =0)

SC K (C P O L =1)

MO SI

MISO

SS