EVB-20022 SMSC Corporation, EVB-20022 Datasheet - Page 4

• Manufacturer Part Number: EVB-20022
• Description: Industrial ARCNET AT Adapter Card
• Manufacturer: SMSC Corporation

I/O Address Selection
The EVB-20022 is a 16 bit I/O mapped card. Addresses A3-A15 are user selectable at switches S2 and S3. For
example, 02E0h would be 000000101110.
Node ID Selection
The EVB-20022 is equipped with an on-board ID switch, S1. The COM20022 network controller requires a software
programmable ID, therefore the switch does not automatically provide a node ID to the COM20022.
COM20022 ICs
The chip can be attached to the board in two different ways: it can either be socketed or it can be mounted right to the
board on U8. Only one or the other can be done, not both.
LEDs
In the front of the card, there are four LEDs. The PWR LED indicates that there is power on the board. The CPU LED
shows CPU I/O activity. The TX LED shows the data being transmitted. The DMA LED shows DMA activity.
Interrupts/DMAs
Use JP1 for interrupt selection. IRQs 3, 4, 5, 6, 7, 9, 10, 11, 12 and 15 can be selected. DACK selection is done at
JP2. DACKs 0, 1, 3, 5, 6 and 7 can be selected. DRQ selection is done at JP3. DRQs 0, 1, 3, 5, 6 and 7 can be
selected. If DMAs are being used, both the DACK and DRQ must both be set to the same value.
Media Interfaces (Transceivers)
The COM20022 supports four types of transceivers:
Software
For evaluation purposes SMSC provides DEMOAT, an MS DOS software utility which can be used to verify and
evaluate the COM20022 evaluation board. DEMOAT was developed at SMSC to both setup and verify basic
functionality of the COM20022 evaluation. The software provides a general user interface, which can be used to
change, or Read/Write register information. This software utility can also be used to both transmit and receive
ARCNET packets. When using this utility in a general network configuration, multiple ARCNET nodes must be
operational. A minimum of two ISA based PCs must be connected via the appropriate cable for correct operation.
Both machines must have the DEMOAT installed and loaded. Once the software is loaded, registers can either be
initialized at their default settings or changed to your custom requirements. At this point traffic can be produced to
send and verify ARCNET frames of data from node to node or PC to PC.
SMSC UG - EVB-20022
ARCNET Coax – operation is valid only at 2.5 Mbps and use SMSC HYC9088 hybrid
Twisted Pair line interface– operation is valid only at 2.5 Mbps
Direct coupled RS-485
Isolated RS-485
Installing DEMOAT
At the a:\ prompt type DEMOAT
Loading DEMOAT software
1.
2.
3.
From within the Arcnet directory Type “Demoat”. When the software loads, it prompts the user for the
ARCNET evaluation board type.
Type “a”, for COM20020 to test COM20022. If a screen comes up asking if the board is a COM20020,
type “y”. The program will ask for the I/O address, type the address in that is selected by S3 and S2,
typically 2e0.
Next, the main menu will come up. When using any of the transceivers except the coax (BNC), you
need to do a setup with option A. If the coax transceiver is being used, go to step 7.
EVB-20022 USER GUIDE
Page 4
Rev. 1/5/00