PIC18C242/JW Microchip Technology, PIC18C242/JW Datasheet - Page 9

• Manufacturer Part Number: PIC18C242/JW
• Description: IC MCU EPROM 8KX16 A/D 28CDIP
• Manufacturer: Microchip Technology
• Series: PIC® 18Cr

Specifications of PIC18C242/JW

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LVD, POR, PWM, WDT
• Number Of I /o: 22
• Program Memory Size: 16KB (8K x 16)
• Program Memory Type: EPROM, UV
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 4.2 V ~ 5.5 V
• Data Converters: A/D 5x10b
• Oscillator Type: External
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 28-CDIP (0.300", 7.62mm) Window
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

6. Module: USART
EXAMPLE 1:
EXAMPLE 2:
 2002 Microchip Technology Inc.
movwf
nop
btfss
movwf
btfss
The operation of the USART Transmit Interrupt
flag bit TXIF (PIR1<4>) is clarified as follows:
TXIF is not cleared immediately upon loading data
into the transmit buffer TXREG. The flag bit
becomes valid in the second instruction cycle fol-
lowing the load instruction (see Example 1). Poll-
ing TXIF immediately following a load of TXREG
will give invalid results (Example 2).
This clarification applies to all USART transmis-
sion modes (master or slave, synchronous or
asynchronous, 8-bit or 9-bit).
TXREG
PIR1,TXIF
TXREG
PIR1,TXIF
CORRECTLY POLLING
THE TXIF BIT
POLLING THE TXIF BIT
IMMEDIATELY AFTER
LOADING THE TRANSMIT
BUFFER
;load the register
:first instruction--
;just a placeholder, it
;could be any instruction
;second instruction--
;now TXIF is valid
;load the register
;first instruction--
;reading TXIF now will
;give invalid results
PIC18CXX2
DS80058H-page 9