MC9S08AW16MFGE Freescale Semiconductor, MC9S08AW16MFGE Datasheet - Page 209

• Manufacturer Part Number: MC9S08AW16MFGE
• Description: IC MCU 8BIT 16K FLASH 44-LQFP
• Manufacturer: Freescale Semiconductor
• Series: HCS08r

Specifications of MC9S08AW16MFGE

• Core Processor: HCS08
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: I²C, SCI, SPI
• Peripherals: LVD, POR, PWM, WDT
• Number Of I /o: 34
• Program Memory Size: 16KB (16K x 8)
• Program Memory Type: FLASH
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 44-LQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

12.3.5
Reads of this register return the data read from the receive data buffer. Writes to this register write data to
the transmit data buffer. When the SPI is configured as a master, writing data to the transmit data buffer
initiates an SPI transfer.
Data should not be written to the transmit data buffer unless the SPI transmit buffer empty flag (SPTEF)
is set, indicating there is room in the transmit buffer to queue a new transmit byte.
Data may be read from SPI1D any time after SPRF is set and before another transfer is finished. Failure
to read the data out of the receive data buffer before a new transfer ends causes a receive overrun condition
and the data from the new transfer is lost.
Freescale Semiconductor
Reset
SPTEF
MODF
SPRF
Field
7
5
4
W
R
SPI Data Register (SPI1D)
Bit 7
SPI Read Buffer Full Flag — SPRF is set at the completion of an SPI transfer to indicate that received data may
be read from the SPI data register (SPI1D). SPRF is cleared by reading SPRF while it is set, then reading the
SPI data register.
0 No data available in the receive data buffer
1 Data available in the receive data buffer
SPI Transmit Buffer Empty Flag — This bit is set when there is room in the transmit data buffer. It is cleared by
reading SPI1S with SPTEF set, followed by writing a data value to the transmit buffer at SPI1D. SPI1S must be
read with SPTEF = 1 before writing data to SPI1D or the SPI1D write will be ignored. SPTEF generates an
SPTEF CPU interrupt request if the SPTIE bit in the SPI1C1 is also set. SPTEF is automatically set when a data
byte transfers from the transmit buffer into the transmit shift register. For an idle SPI (no data in the transmit buffer
or the shift register and no transfer in progress), data written to SPI1D is transferred to the shifter almost
immediately so SPTEF is set within two bus cycles allowing a second 8-bit data value to be queued into the
transmit buffer. After completion of the transfer of the value in the shift register, the queued value from the
transmit buffer will automatically move to the shifter and SPTEF will be set to indicate there is room for new data
in the transmit buffer. If no new data is waiting in the transmit buffer, SPTEF simply remains set and no data
moves from the buffer to the shifter.
0 SPI transmit buffer not empty
1 SPI transmit buffer empty
Master Mode Fault Flag — MODF is set if the SPI is configured as a master and the slave select input goes
low, indicating some other SPI device is also configured as a master. The SS pin acts as a mode fault error input
only when MSTR = 1, MODFEN = 1, and SSOE = 0; otherwise, MODF will never be set. MODF is cleared by
reading MODF while it is 1, then writing to SPI control register 1 (SPI1C1).
0 No mode fault error
1 Mode fault error detected
0
7
6
0
6
Table 12-7. SPI1S Register Field Descriptions
Figure 12-9. SPI Data Register (SPI1D)
5
0
5
MC9S08AW60 Data Sheet, Rev 2
4
0
4
Description
3
3
0
Chapter 12 Serial Peripheral Interface (S08SPIV3)
2
0
2
1
0
1
Bit 0
0
0
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