PIC18F2685-I/SP Microchip Technology, PIC18F2685-I/SP Datasheet - Page 328

• Manufacturer Part Number: PIC18F2685-I/SP
• Description: IC PIC MCU FLASH 48KX16 28-DIP
• Manufacturer: Microchip Technology
• Series: PIC® 18Fr

Specifications of PIC18F2685-I/SP

• Program Memory Type: FLASH
• Program Memory Size: 96KB (48K x 16)
• Package / Case: 28-DIP (0.300", 7.62mm)
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: CAN, I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, HLVD, POR, PWM, WDT
• Number Of I /o: 25
• Eeprom Size: 1K x 8
• Ram Size: 3.25K x 8
• Voltage - Supply (vcc/vdd): 4.2 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Processor Series: PIC18F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 3.25 KB
• Interface Type: EUSART/I2C/MSSP/SPI
• Maximum Clock Frequency: 40 MHz
• Number Of Programmable I/os: 28
• Number Of Timers: 4
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734, 52712-325, EWPIC18
• Development Tools By Supplier: PG164130, DV164035, DV244005, DV164005, PG164120, ICE2000, DV164136
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 8-ch x 10-bit
• Package: 28SPDIP
• Device Core: PIC
• Family Name: PIC18
• Maximum Speed: 40 MHz
• Operating Supply Voltage: 5 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: DVA18XP280 - DEVICE ADAPTER 18F2220 PDIP 28LD
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

PIC18F2682/2685/4682/4685
23.3.4
Listen Only mode provides a means for the
PIC18F2682/2685/4682/4685 devices to receive all
messages, including messages with errors. This mode
can be used for bus monitor applications or for
detecting the baud rate in ‘hot plugging’ situations. For
Auto-Baud Detection, it is necessary that there are at
least two other nodes which are communicating with
each other. The baud rate can be detected empirically
by testing different values until valid messages are
received. The Listen Only mode is a silent mode,
meaning no messages will be transmitted while in this
state, including error flags or Acknowledge signals. The
filters and masks can be used to allow only particular
messages to be loaded into the receive registers or the
filter masks can be set to all zeros to allow a message
with any identifier to pass. The error counters are reset
and deactivated in this state. The Listen Only mode is
activated by setting the mode request bits in the
CANCON register.
23.3.5
This mode will allow internal transmission of messages
from the transmit buffers to the receive buffers without
actually transmitting messages on the CAN bus. This
mode can be used in system development and testing.
In this mode, the ACK bit is ignored and the device will
allow incoming messages from itself, just as if they
were coming from another node. The Loopback mode
is a silent mode, meaning no messages will be
transmitted while in this state, including error flags or
Acknowledge signals. The TXCAN pin will revert to port
I/O while the device is in this mode. The filters and
masks can be used to allow only particular messages
to be loaded into the receive registers. The masks can
be set to all zeros to provide a mode that accepts all
messages. The Loopback mode is activated by setting
the mode request bits in the CANCON register.
23.3.6
The module can be set to ignore all errors and receive
any message. In functional Mode 0, the Error Recogni-
tion mode is activated by setting the RXM<1:0> bits in
the RXBnCON registers to ‘11’. In this mode, the data
which is in the message assembly buffer until the error
time, is copied in the receive buffer and can be read via
the CPU interface.
DS39761C-page 328
LISTEN ONLY MODE
LOOPBACK MODE
ERROR RECOGNITION MODE
register can be used as a data byte filter. The length of
protocols, such as the DeviceNet™ protocol.
23.4
In addition to CAN modes of operation, the ECAN mod-
ule offers a total of 3 functional modes. Each of these
modes are identified as Mode 0, Mode 1 and Mode 2.
23.4.1
Mode 0 is designed to be fully compatible with CAN
modules used in PIC18CXX8 and PIC18FXX8 devices.
This is the default mode of operation on all Reset
conditions. As a result, module code written for the
PIC18XX8 CAN module may be used on the ECAN
module without any code changes.
The following is the list of resources available in Mode 0:
• Three transmit buffers: TXB0, TXB1 and TXB2
• Two receive buffers: RXB0 and RXB1
• Two acceptance masks, one for each receive
• Six acceptance filters, 2 for RXB0 and 4 for RXB1:
23.4.2
Mode 1 is similar to Mode 0, with the exception that more
resources are available in Mode 1. There are
16 acceptance filter registers and two acceptance mask
registers. Acceptance Filter 15 can be used as either an
acceptance filter or an acceptance mask register. In
addition to three transmit and two receive buffers, there
are six more message buffers. One or more of these
additional buffers can be programmed as transmit or
receive buffers. These additional buffers can also be
programmed to automatically handle RTR messages.
Fourteen of sixteen acceptance filter registers can be
dynamically associated to any receive buffer and
acceptance mask register. One can use this capability
to associate more than one filter to any one buffer.
When a receive buffer is programmed to use standard
identifier messages, part of the full acceptance filter
the data byte filter is programmable from 0 to 18 bits.
This functionality simplifies implementation of high-level
The following is the list of resources available in Mode 1:
• Three transmit buffers: TXB0, TXB1 and TXB2
• Two receive buffers: RXB0 and RXB1
• Six buffers programmable as TX or RX: B0-B5
• Automatic RTR handling on B0-B5
• Sixteen dynamically assigned acceptance filters:
• Two dedicated acceptance mask registers;
• Programmable data filter on standard identifier
buffer: RXM0, RXM1
RXF0, RXF1, RXF2, RXF3, RXF4, RXF5
RXF0-RXF15
RXF15 programmable as third mask:
RXM0-RXM1, RXF15
messages: SDFLC
ECAN Module Functional Modes
MODE 0 – LEGACY MODE
MODE 1 – ENHANCED
LEGACY MODE
© 2009 Microchip Technology Inc.