Microchip Technology Inc.: New flash microcontrollers switch between CAN and FIFO mode

The Control Area Network (CAN) product lineup of Microchip Technology Inc. has recently expanded with a new generation of 48 KB and 64 KB flash memory microcontroller.

By Control Engineering Staff September 8, 2003

Microchip’s new 8-bit PICmicro MCUs target complex embedded command-and-control networks in automotive and general-purpose markets. They’re available now in 64- and 80-lead TQFP and 68-lead PLCC packages.

The Control Area Network (CAN) product lineup of Microchip Technology Inc . has recently expanded with a new generation of 48 KB and 64 KB flash memory microcontrollers (PIC18F8680/6680 and PIC18F8585/6585) that integrate a new, flexible CAN 2.0B interface. Called ECAN module, the interface features configurable transmit and receive (TX/RX) buffers, offering either standard CAN operation or FIFO (first in, first out) data mode.

Benefits of ECAN module include ability to configure multiple applications on a single node; easier implementation to a software-protocol bridge from a CAN network, and allowing the microcontroller (MCU) to be reused for different applications. ECAN module’s three software-configurable operating modes support multiple functions (including DeviceNet):

Mode 0 (Legacy) permits reuse of application code previously developed for Microchip’s existing PIC18CX58 or PIC18FXX8 CAN interface MCUs.

Mode 1(Enhanced) supplies added resources and wider functionality, including three dedicated TX buffers, two dedicated RX buffers, and six independently configurable TX/RX buffers. Also featured are 16 acceptance filters, two filter masks, and an automatic remote transmission request response.

Mode 2 (FIFO) provides RX buffers set up in a FIFO configuration (not directly associated with a given acceptance filter). CAN bus messages are stored in the eight FIFO buffers based on the sequence in which they are received.

Demonstration boards—PICDEM CAN LIN 1 and 2—are available for $199 each to show the CAN module’s functionality on PIC18CX58 and PIC18FXX8 devices. The kits include preprogrammed firmware on a sample device, PC software, and documentation for simulating a CAN network.

—Frank J. Bartos, executive editor, fbartos@reedbusiness.com