s908ey8ad4cfjer Freescale Semiconductor, Inc, s908ey8ad4cfjer Datasheet - Page 176

• Manufacturer Part Number: s908ey8ad4cfjer
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Serial Peripheral Interface (SPI) Module
15.6 Error Conditions
Two flags signal SPI error conditions:
176
1. Overflow (OVRF in SPSCR) — Failing to read the SPI data register before the next byte enters the
2. Mode fault error (MODF in SPSCR) — The MODF bit indicates that the voltage on the slave select
shift register sets the OVRF bit. The new byte does not transfer to the receive data register, and
the unread byte still can be read by accessing the SPI data register. OVRF is in the SPI status and
control register.
pin (SS) is inconsistent with the mode of the SPI. MODF is in the SPI status and control register.
SCK CYCLE
NUMBER
CPHA = 1
CPHA = 0
SCK
SCK
CLOCK
CLOCK
CLOCK
CLOCK
CLOCK
BUS
BUS
BUS
BUS
BUS
MOSI
TO SPDR
TO SPDR
TO SPDR
TO SPDR
WRITE
WRITE
WRITE
WRITE
Figure 15-6. Transmission Start Delay (Master)
TO SPDR
MC68HC908EY16 • MC68HC908EY8 Data Sheet, Rev. 10
WRITE
EARLIEST LATEST
EARLIEST
EARLIEST
EARLIEST
INITIATION DELAY FROM WRITE SPDR TO TRANSFER BEGIN
SCK = INTERNAL CLOCK ÷ 128;
INITIATION DELAY
SCK = INTERNAL CLOCK ÷ 32;
128 POSSIBLE START POINTS
SCK = INTERNAL CLOCK ÷ 2;
SCK = INTERNAL CLOCK ÷ 8;
32 POSSIBLE START POINTS
2 POSSIBLE START POINTS
8 POSSIBLE START POINTS
MSB
1
BIT 6
2
LATEST
LATEST
LATEST
BIT 5
3
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