XC705B32CFNE Freescale Semiconductor, XC705B32CFNE Datasheet - Page 81

• Manufacturer Part Number: XC705B32CFNE
• Description: IC MCU 2.1MHZ 32K OTP 52-PLCC
• Manufacturer: Freescale Semiconductor
• Series: HC05r

Specifications of XC705B32CFNE

• Core Processor: HC05
• Core Size: 8-Bit
• Speed: 2.1MHz
• Connectivity: SCI
• Peripherals: POR, WDT
• Number Of I /o: 32
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: OTP
• Eeprom Size: 256 x 8
• Ram Size: 528 x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Data Converters: A/D 8x8b; D/A 2x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 52-PLCC
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

6.10
The SCI transmitter allows the user to control a one way synchronous serial transmission. The
SCLK pin is the clock output of the SCI transmitter. No clocks are sent to that pin during start bit
and stop bit. Depending on the state of the LBCL bit (bit 0 of SCCR1), clocks will or will not be
activated during the last valid data bit (address mark). The CPOL bit (bit 2 of SCCR1) allows the
user to select the clock polarity, and the CPHA bit (bit 1 of SCCR1) allows the user to select the
phase of the external clock (see
During idle, preamble and send break, the external SCLK clock is not activated.
These options allow the user to serially control peripherals which consist of shift registers, without
losing any functions of the SCI transmitter which can still talk to other SCI receivers. These options
do not affect the SCI receiver which is independent of the transmitter.
The SCLK pin works in conjunction with the TDO pin. When the SCI transmitter is disabled
(TE = 0), the SCLK and TDO pins go to the high impedance state.
Note:
MC68HC05B6
Rev. 4.1
The LBCL, CPOL and CPHA bits have to be selected before enabling the transmitter
to ensure that the clocks function correctly. These bits should not be changed while the
transmitter is enabled.
Figure 6-8 SCI example of synchronous and asynchronous transmission
SCI synchronous transmission
MC68HC05B6
Output port
SERIAL COMMUNICATIONS INTERFACE
SCLK
TDO
RDI
Figure
6-8,
Figure 6-9
Data out
Data in
Data in
Clock
Enable
and
Figure
display driver, etc.)
6-10).
(e.g. shift register,
Asynchronous
(e.g. Modem)
Synchronous
Freescale
6-9
6