MC68HC708AS48 FREESCALE [Freescale Semiconductor, Inc], MC68HC708AS48 Datasheet - Page 315

• Manufacturer Part Number: MC68HC708AS48
• Description: Advance Information
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

MC68HC708AS48
MOTOROLA
—
Rev. 4.0
SPR1 and SPR0 — SPI Baud Rate Select Bits
Use this formula to calculate the SPI baud rate:
where:
If the MODFEN bit is low, the level of the SS pin does not affect the
operation of an enabled SPI configured as a master. For an enabled
SPI configured as a slave, having MODFEN low only prevents the
MODF flag from being set. It does not affect any other part of SPI
operation. (See
In master mode, these read/write bits select one of four baud rates as
shown in
Reset clears SPR1 and SPR0.
CGMOUT = base clock output of the clock generator module (CGM),
see
BD = baud rate divisor
Section 8. Clock Generator Module
SPR1:SPR0
Serial Peripheral Interface (SPI)
Baud rate
Table
Table 18-5. SPI Master Baud Rate Selection
00
01
10
11
18-5. SPR1 and SPR0 have no effect in slave mode.
18.7.2 Mode Fault
=
CGMOUT
------------------------- -
2 BD
=
Error.)
Bus clock
------------------------ -
Baud Rate Divisor (BD)
BD
Serial Peripheral Interface (SPI)
(CGM).
128
32
2
8
Advance Information
I/O Registers
315