S912XET256J2VAGR Freescale Semiconductor, S912XET256J2VAGR Datasheet - Page 784

• Manufacturer Part Number: S912XET256J2VAGR
• Description: 16-bit Microcontrollers - MCU Watchdog OSC/Timer -40 C to + 105 C HCS12X MCU SPI
• Manufacturer: Freescale Semiconductor

Specifications of S912XET256J2VAGR

• Core: HCS12X
• Data Bus Width: 16 bit
• Maximum Clock Frequency: 50 MHz
• Program Memory Size: 256 KB
• Data Ram Size: 16 KB
• On-chip Adc: Yes
• Package / Case: LQFP
• Mounting Style: SMD/SMT
• A/d Bit Size: 12 bit
• A/d Channels Available: 24
• Interface Type: CAN, SCI, SPI
• Maximum Operating Temperature: + 105 C
• Minimum Operating Temperature: - 40 C
• Number Of Programmable I/os: 119
• Number Of Timers: 25
• Program Memory Type: Flash
• Supply Voltage - Max: 1.98 V, 2.9 V, 5.5 V
• Supply Voltage - Min: 1.72 V, 2.7 V, 3.13 V

Chapter 21 Serial Peripheral Interface (S12SPIV5)
the SPI system is configured as a slave, the SS pin is a dedicated input pin. Mode fault error doesn’t occur
in slave mode.
If a mode fault error occurs, the SPI is switched to slave mode, with the exception that the slave output
buffer is disabled. So SCK, MISO, and MOSI pins are forced to be high impedance inputs to avoid any
possibility of conflict with another output driver. A transmission in progress is aborted and the SPI is
forced into idle state.
If the mode fault error occurs in the bidirectional mode for a SPI system configured in master mode, output
enable of the MOMI (MOSI in bidirectional mode) is cleared if it was set. No mode fault error occurs in
the bidirectional mode for SPI system configured in slave mode.
The mode fault flag is cleared automatically by a read of the SPI status register (with MODF set) followed
by a write to SPI control register 1. If the mode fault flag is cleared, the SPI becomes a normal master or
slave again.
21.4.7
21.4.7.1
In run mode with the SPI system enable (SPE) bit in the SPI control register clear, the SPI system is in a
low-power, disabled state. SPI registers remain accessible, but clocks to the core of this module are
disabled.
21.4.7.2
SPI operation in wait mode depends upon the state of the SPISWAI bit in SPI control register 2.
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– If SPISWAI is set and the SPI is configured for master, any transmission and reception in
– If SPISWAI is set and the SPI is configured as a slave, any transmission and reception in
If SPISWAI is clear, the SPI operates normally when the CPU is in wait mode
If SPISWAI is set, SPI clock generation ceases and the SPI module enters a power conservation
state when the CPU is in wait mode.
progress stops at wait mode entry. The transmission and reception resumes when the SPI exits
wait mode.
progress continues if the SCK continues to be driven from the master. This keeps the slave
synchronized to the master and the SCK.
If the master transmits several bytes while the slave is in wait mode, the slave will continue to
send out bytes consistent with the operation mode at the start of wait mode (i.e., if the slave is
currently sending its SPIDR to the master, it will continue to send the same byte. Else if the
slave is currently sending the last received byte from the master, it will continue to send each
previous master byte).
Low Power Mode Options
SPI in Run Mode
SPI in Wait Mode
If a mode fault error occurs and a received data byte is pending in the receive
shift register, this data byte will be lost.
MC9S12XE-Family Reference Manual Rev. 1.25
NOTE
Freescale Semiconductor