mc68hc912bc32 Freescale Semiconductor, Inc, mc68hc912bc32 Datasheet - Page 123

• Manufacturer Part Number: mc68hc912bc32
• Description: M68hc12 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Freescale Semiconductor
P CLOCK
÷
÷
÷
÷
÷
÷
÷
÷
2
2
2
2
2
2
2
2
BITS: SPR2, SPR1, AND SPR0
REGISTER: SP0BR
0:0:1
0:1:0
0:1:1
1:0:0
1:0:1
1:1:0
1:1:1
0:0:0
Figure 10-13. Clock Chain for SPI, ATD, and BDM
COUNTER (PR0-PR4)
5-BIT MODULUS
M68HC12B Family Data Sheet, Rev. 9.1
BIT RATE
SPI
SYNCHRONIZER
E CLOCK
LOGIC
BKGD
PIN
÷
2
BKGD DIRECTION
BKGD OUT
BKGD IN
TO ATD
BDM BIT CLOCK:
Receive: Detect falling edge,
count 12 E clocks, sample input
Transmit 1: Detect falling edge,
count 6 E clocks while output is
high impedance, drive out 1 E
cycle pulse high,
high-impedance output again
Transmit 0: Detect falling edge,
drive out low, count 9 E clocks,
drive out 1 E cycle pulse high,
high-impedance output
Clock Divider Chains
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