ARCNET Evaluation System Legacy Product

Good simulation tools are essential in the process of embedded software development. That's why Contemporary Controls designed the ARCNET Evaluation System (ARC-EVS)-blending unique ARCNET features and functionality into a learning tool for exploring embedded ARCNET. By employing the hardware and software provided in the ARC-EVS, the user can have a demonstration system "up and running" in less than 10 minutes. The user supplies the PC with a Windows OS and everything else is in the kit. The kit contains: one PCI20U-485X ARCNET interface adapter (for installation in a PCI slot in the PC); one ARC-EVB ARCNET evaluation board with 8 input switches and 8 LED outputs; power supply; RJ-11 cable to connect the PCI20U-485X to the ARC-EVB; two terminators to terminate the ends of the network cable; software drivers for Windows 95, 98, 2000, NT and XP; sample application software to read and display the input status and to control the LED outputs; and one null modem cable to do a serial download and debugging of an application program.

The product's key element is the ARC-EVB designed with an Atmel T89C51 microcontroller. The microcontroller contains 16 kB of FLASH memory to hold the test application (Modbus over ARCNET)-or the user's firmware. This enables the user to download their firmware into FLASH and execute it. The FLASH memory can also hold the Keil monitor, permitting users to debug their embedded ARCNET code on the board.

The board is also equipped with the SMSC COM20022 ARCNET controller (backward compatible with the COM20020) which supports data rates from 156 kbps to 10 Mbps using a 20 MHz crystal.

The ARC-EVS functions in three modes. The first mode is the Keil debug mode in which the board will execute a Keil monitor program. The user will download his application into the board's RAM and control its execution through the Keil debugger. In the second mode the user can program the Atmel microcontroller with the ARCNET firmware allowing communication with a Windows PC using the provided PCI20U card and the sample Windows application. The third mode lets the user download and execute his own firmware in the FLASH memory of the board.

The sample Windows application lets the user view and set 8 bits of I/O on the ARC-EVB via the special Modbus over ARCNET protocol. An 8-position DIP switch acts as the input device and 8 associated LEDs report the state of each input. An additional 8 LEDs indicate the status of the output signals. The PCI20U-485X is a PCI-based ARCNET interface adapter containing the same ARCNET controller (COM20022). When the card is inserted in a computer and connected to the ARC-EVB via the RJ-11 cable, a fully functional network is created.