AT89C5122 ATMEL [ATMEL Corporation], AT89C5122 Datasheet - Page 143

• Manufacturer Part Number: AT89C5122
• Description: MICROCONTROLLER WITH USB AND SMART CARD READER INTERFACES
• Manufacturer: ATMEL [ATMEL Corporation]

Registers
Serial Peripheral Control
Register (SPCON)
4202D–SCR–06/05
Mode Fault flag, MODF: This bit becomes set to indicate that the level on the SS is
inconsistent with the mode of the SPI. MODF with SSDIS reset, generates receiver/error
CPU interrupt requests.
Figure 89 gives a logical view of the above statements.
Figure 89. SPI Interrupt Requests Generation
There are three registers in the module that provide control, status and data storage
functions. These registers are describes in the following paragraphs.
The Serial Peripheral Control Register does the following:
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•
•
•
•
Selects one of the Master clock rates
Configures the SPI module as Master or Slave
Selects serial clock polarity and phase
Enables the SPI module
Frees the SS pin for a general-purpose
SPIF
MODF
SSDIS
CPU Interrupt Request
SPI Transmitter
SPI Receiver/error
CPU Interrupt Request
CPU Interrupt Request
SPI
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