MC68HC908KX2CP Freescale Semiconductor, MC68HC908KX2CP Datasheet - Page 116

• Manufacturer Part Number: MC68HC908KX2CP
• Description: IC MCU 2K FLASH 8MHZ SCI 16-DIP
• Manufacturer: Freescale Semiconductor
• Series: HC08r

Specifications of MC68HC908KX2CP

• Core Processor: HC08
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: SCI
• Peripherals: LVD, POR, PWM
• Number Of I /o: 13
• Program Memory Size: 2KB (2K x 8)
• Program Memory Type: FLASH
• Ram Size: 192 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 4x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 16-DIP (0.300", 7.62mm)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

Serial Communications Interface Module (SCI)
At the start of a transmission, transmitter control logic automatically loads the transmit shift register with
a preamble of logic 1s. After the preamble shifts out, control logic transfers the SCDR data into the
transmit shift register. A logic 0 start bit automatically goes into the least significant bit position of the
transmit shift register. A logic 1 stop bit goes into the most significant bit position.
The SCI transmitter empty bit, SCTE, in SCS1 becomes set when the SCDR transfers a byte to the
transmit shift register. The SCTE bit indicates that the SCDR can accept new data from the internal data
bus. If the SCI transmit interrupt enable bit, SCTIE, in SCC2 is also set, the SCTE bit generates a
transmitter CPU interrupt request.
When the transmit shift register is not transmitting a character, the TxD pin goes to the idle condition,
logic 1. If at any time software clears the ENSCI bit in SCI control register 1 (SCC1), the transmitter and
receiver relinquish control of the port B pins.
Writing a 1 to the send break bit, SBK, in SCC2 loads the transmit shift register with a break character. A
break character contains all logic 0s and has no start, stop, or parity bit. Break character length depends
on the M bit in SCC1. As long as SBK is at 1, transmitter logic continuously loads break characters into
the transmit shift register. After software clears the SBK bit, the shift register finishes transmitting the last
116
SCR1
SCR2
SCR0
SCP1
SCP0
÷
4
MC68HC908KX8 • MC68HC908KX2 • MC68HC08KX8 Data Sheet, Rev. 2.1
SCALER
PRE-
Figure 12-5. SCI Transmitter Break Characters
DIVIDER
BAUD
PEN
PTY
TXINV
÷
GENERATION
16
PARITY
SCTE
SCTIE
TC
TCIE
T8
M
H
8
SCTIE
7
SCTE
TCIE
TC
SCI DATA REGISTER
6
SHIFT REGISTER
INTERNAL BUS
TRANSMIT
5
11-BIT
4
CONTROL LOGIC
TRANSMITTER
3
2
1
LOOPS
ENSCI
SBK
TE
0
L
Freescale Semiconductor
TxD