PIC18F452-I/L Microchip Technology Inc., PIC18F452-I/L Datasheet - Page 176

• Manufacturer Part Number: PIC18F452-I/L
• Description: 44 PIN, 32 KB FLASH, 1536 RAM, 34 I/O
• Manufacturer: Microchip Technology Inc.

Specifications of PIC18F452-I/L

• A/d Inputs: 8-Channel, 10-Bit
• Comparators: 2
• Cpu Speed: 10 MIPS
• Eeprom Memory: 256 Bytes
• Input Output: 36
• Interface: I2C/SPI/USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 44-pin PLCC
• Programmable Memory: 32K Bytes
• Ram Size: 1.5K Bytes
• Speed: 40 MHz
• Timers: 1-8-bit, 3-16-bit
• Voltage, Range: 2-5.5 V
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

PIC18FXX2
16.2.2
The receiver block diagram is shown in Figure 16-4.
The data is received on the RC7/RX/DT pin and drives
the data recovery block. The data recovery block is
actually a high speed shifter operating at x16 times the
baud rate, whereas the main receive serial shifter oper-
ates at the bit rate or at F
typically be used in RS-232 systems.
To set up an Asynchronous Reception:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10. If using interrupts, ensure that the GIE and PEIE
FIGURE 16-4:
DS39564C-page 174
Initialize the SPBRG register for the appropriate
baud rate. If a high speed baud rate is desired,
set bit BRGH (Section 16.1).
Enable the asynchronous serial port by clearing
bit SYNC and setting bit SPEN.
If interrupts are desired, set enable bit RCIE.
If 9-bit reception is desired, set bit RX9.
Enable the reception by setting bit CREN.
Flag bit RCIF will be set when reception is com-
plete and an interrupt will be generated if enable
bit RCIE was set.
Read the RCSTA register to get the ninth bit (if
enabled) and determine if any error occurred
during reception.
Read the 8-bit received data by reading the
RCREG register.
If any error occurred, clear the error by clearing
enable bit CREN.
bits in the INTCON register (INTCON<7:6>) are
set.
RC7/RX/DT
USART ASYNCHRONOUS
RECEIVER
Baud Rate Generator
x64 Baud Rate CLK
USART RECEIVE BLOCK DIAGRAM
SPBRG
Pin Buffer
and Control
SPEN
OSC
. This mode would
Data
Recovery
Interrupt
or
64
16
CREN
16.2.3
This mode would typically be used in RS-485 systems.
To set up an Asynchronous Reception with Address
Detect Enable:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10. If any error occurred, clear the CREN bit.
11. If the device has been addressed, clear the
RX9
STOP
Initialize the SPBRG register for the appropriate
baud rate. If a high speed baud rate is required,
set the BRGH bit.
Enable the asynchronous serial port by clearing
the SYNC bit and setting the SPEN bit.
If interrupts are required, set the RCEN bit and
select the desired priority level with the RCIP bit.
Set the RX9 bit to enable 9-bit reception.
Set the ADDEN bit to enable address detect.
Enable reception by setting the CREN bit.
The RCIF bit will be set when reception is com-
plete. The interrupt will be acknowledged if the
RCIE and GIE bits are set.
Read the RCSTA register to determine if any
error occurred during reception, as well as read
bit 9 of data (if applicable).
Read RCREG to determine if the device is being
addressed.
ADDEN bit to allow all received data into the
receive buffer and interrupt the CPU.
MSb
RCIF
RCIE
RX9D
(8)
SETTING UP 9-BIT MODE WITH
ADDRESS DETECT
OERR
7
RSR Register
RCREG Register
8
Data Bus
© 2006 Microchip Technology Inc.
1
FERR
0
START
LSb
FIFO