Rainbow-electronics AT89LP214 Manuel d'utilisateur télécharger pdf (Page 74)

3538A–MICRO–7/06

AT89LP213/214 [Preliminary]

23.8.5 Serial Peripheral Interface

The Serial Peripheral Interface (SPI) is a byte-oriented full duplex synchronous serial communi-

cation channel. During In-System programming the programmer always acts as the SPI master

and the target device always acts as the SPI slave. The target device receives serial data on

MOSI and outputs serial data on MISO. The Programming Interface implements a standard

SPI Port with a fixed data order and For In-System programming, bytes are transferred MSB first

as shown in Figure 23-9. The SCK phase and polarity follow SPI clock mode 0 (CPOL = 0,

CPHA = 0) where bits are sampled on the rising edge of SCK and output on the falling edge of

SCK. For more detailed timing information see Figure 23-10.

Figure 23-9. ISP Byte Sequence

Figure 23-10. Serial Programming Interface Timing

MOSI

MISO

SCK

Data Sampled

SSE

SLSH

SOV

SOX

SSD

SCK

SHSL

SOE

SOH

SIH

SIS

SCK

MISO

MOSI

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Rainbow-electronics AT89LP214 Manuel d'utilisateur Page 74