PIC18F2431-I/SO Microchip Technology, PIC18F2431-I/SO Datasheet - Page 168

• Manufacturer Part Number: PIC18F2431-I/SO
• Description: IC PIC MCU FLASH 8KX16 28SOIC
• Manufacturer: Microchip Technology
• Series: PIC® 18Fr

Specifications of PIC18F2431-I/SO

• Program Memory Type: FLASH
• Program Memory Size: 16KB (8K x 16)
• Package / Case: 28-SOIC (7.5mm Width)
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LVD, Power Control PWM, QEI, POR, PWM, WDT
• Number Of I /o: 24
• Eeprom Size: 256 x 8
• Ram Size: 768 x 8
• Voltage - Supply (vcc/vdd): 4.2 V ~ 5.5 V
• Data Converters: A/D 5x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Processor Series: PIC18F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 768 B
• Interface Type: EUSART/I2C/SPI/SSP
• Maximum Clock Frequency: 40 MHz
• Number Of Programmable I/os: 24
• Number Of Timers: 4
• Operating Supply Voltage: 2 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734, 52712-325, EWPIC18
• Development Tools By Supplier: PG164130, DV164035, DV244005, DV164005, PG164120, ICE2000, ICE4000, DM183021, DV164136
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 5-ch x 10-bit
• Package: 28SOIC W
• Device Core: PIC
• Family Name: PIC18
• Maximum Speed: 40 MHz
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: XLT28SO-1 - SOCKET TRANSITION 28SOIC 300MILI3-DB18F4431 - BOARD DAUGHTER ICEPIC3
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

PIC18F2331/2431/4331/4431
FIGURE 17-13:
17.2.6.2
The velocity event pulse (velcap, see
serves as the TMR5 capture trigger to IC1 while in the
Velocity mode. The number of velocity events are
reduced by the velocity postscaler before they are used
as the input capture clock. The velocity event reduction
ratio can be set with the PDEC<1:0> control bits
(QEICON<1:0>) to 1:4, 1:16, 1:64 or no reduction (1:1).
The velocity postscaler settings are automatically
reloaded from their previous values as the Velocity
mode is re-enabled.
DS39616D-page 168
Note 1: Timing shown is for QEIM<2:0> = 101, 110 or 111 (x4 Update mode enabled) and the velocity postscaler divide ratio
QEA
QEB
vel_out
velcap
TMR5
VELR
cnt_reset
IC1IF
CAP1REN
Instr.
Execution
2: The VELR register latches the TMR5 count on the “velcap” capture pulse. Timer5 must be set to the Synchronous Timer
3: The TMR5 counter is reset on the next Q1 clock cycle following the “velcap” pulse. The TMR5 value is unaffected
4: IC1IF interrupt is enabled by setting IC1IE as follows: BSF PIE2, IC1IE. Assume IC1E bit is placed in the PIE2
5: The post decimation value is changed from PDEC = 01 (decimate by 4) to PDEC = 00 (decimate by 1).
is set to divide-by-4 (PDEC<1:0> = 01).
or Counter mode. In this example, it is set to the Synchronous Timer mode, where the TMR5 prescaler divide ratio = 1
(i.e., Timer5 Clock = T
when the Velocity Measurement mode is first enabled (VELM = 0). The velocity postscaler values must be
reconfigured to their previous settings when re-entering Velocity Measurement mode. While making speed
measurements of very slow rotational speeds (e.g., servo-controller applications), the Velocity Measurement mode
may not provide sufficient precision. The Pulse-Width Measurement mode may have to be used to provide the
additional precision. In this case, the input pulse is measured on the CAP1 input pin.
(Peripheral Interrupt Enable 2) register in the target device. The actual IC1IF bit is written on the Q2 rising edge.
(4)
(2)
(2)
Velocity Postscaler
(3)
BCF T5CON, VELM
VELOCITY MEASUREMENT TIMING
Old Value
CY
BCF PIE2, IC1IE
).
Figure
Q1
17-12)
BSF PIE2, IC1IE
Forward
1529
Q1
17.2.6.3
The TMR5 value can be reset (TMR5 register
pair = 0000h) on a velocity event capture by setting
the CAP1REN bit (CAP1CON<6>). When CAP1REN
is cleared, the TMR5 time base will not be reset on
any velocity event capture pulse. The VELR register
pair, however, will continue to be updated with the
current TMR5 value.
(1)
MOVWF QEICON
1537
Reverse
CAP1REN in Velocity Mode
(5)
Q1
 2010 Microchip Technology Inc.