MC68HC908GR8CD Freescale Semiconductor, MC68HC908GR8CD Datasheet - Page 184

• Manufacturer Part Number: MC68HC908GR8CD
• Description: 8-bit Microcontrollers - MCU 8 Bit 8MHz
• Manufacturer: Freescale Semiconductor

Specifications of MC68HC908GR8CD

• Product Category: 8-bit Microcontrollers - MCU
• Rohs: yes
• Core: HC08
• Data Bus Width: 8 bit
• Maximum Clock Frequency: 8 MHz
• Program Memory Size: 64 KB
• Data Ram Size: 384 B
• Operating Supply Voltage: 3 V to 5 V
• Package / Case: SOIC-28
• Mounting Style: SMD/SMT
• Data Rom Size: 64 KB
• Maximum Operating Temperature: + 125 C
• Minimum Operating Temperature: - 40 C
• Number Of Programmable I/os: 21
• Program Memory Type: Flash

Serial Communications Interface (SCI)
SCP1 and SCP0 — SCI Baud Rate Prescaler Bits
SCR2–SCR0 — SCI Baud Rate Select Bits
Use this formula to calculate the SCI baud rate:
where:
SCIBDSRC from the configuration register is an input to the SCI. With SCIBDSRC = 1 to select the bus
clock as the clock source, this makes the formula:
Table 18-8
184
These read/write bits select the baud rate prescaler divisor as shown in
and SCP0.
These read/write bits select the SCI baud rate divisor as shown in
SCR2–SCR0.
f
PD = prescaler divisor
BD = baud rate divisor
BUS
= bus frequency
shows the SCI baud rates that can be generated with a 4.9152-MHz bus clock.
SCR2, SCR1, and SCR0
MC68HC908GR8 • MC68HC908GR4 Data Sheet, Rev. 7
SCP1 and SCP0
Table 18-6. SCI Baud Rate Prescaling
baud rate
Table 18-7. SCI Baud Rate Selection
baud rate
000
001
010
011
100
101
110
111
00
01
10
11
=
=
----------------------------------- -
64
----------------------------------- -
64
×
f BUS
×
PD BD
f BUS
PD BD
×
×
Baud Rate Divisor (BD)
Prescaler Divisor (PD)
128
13
16
32
64
1
3
4
1
2
4
8
Table
Table
18-7. Reset clears
18-6. Reset clears SCP1
Freescale Semiconductor