BeebMaster - I Want an Econet! - Build your own Econet

Build your own Econet

Testing the Network

Once the network has been wired up, it is helpful to test that everything is working. At this stage, only a limited amount of testing can be done unless you already have a file server running. It may be necessary to repeat the test procedure later once your file server is set up.

What follows below is a guide to some simple tests you can carry out on your network to make sure everything is connected up properly together with some troubleshooting ideas to combat the most likely errors you may encounter.

Initial Test

The first thing to do is to switch everything on. Turn on all your networked Beebs, switch on the Clock and switch on the terminators if you are using powered terminators.

Reset each BBC into the Network filing system by holding down N and pressing BREAK. This will instantly tell us whether the machine is configured correctly for Econet and whether the clock signal is being detected.

If the message "Econet Station xxx" does not appear on screen, follow the suggestions under "Can't select NFS" below.

If the message "No clock" appears in the Econet Station line, follow the suggestions under "No Clock error" below.

The next step is to try issuing a command across the network. Enter something like *. or *I AM etc.

After a few seconds, you should get a response. Don't worry about a "not listening" error because at this stage the file server is not likely to be running so this is perfectly normal. If you get "No clock", "Line Jammed" or "Net error" then follow the suggestions under these headings below.

Can't select NFS

If N-BREAK does not initialise the Econet filing system or *NET produces a Bad Command error, then check the following:

1. Make sure the computer is fitted with NFS for the BBC Model B or ANFS for the BBC Master. Use *ROMS or *HELP to check for the presence of NFS. Make sure the ROM number is not unplugged in a Master Series machine.

2. If the NFS is present, check that the Econet interface is correctly installed. Make sure the Econet module is properly aligned in the Master Series machines and check that all the components to the Model B Econet upgrade have been fitted.

Master Waits Indefinitely

Certain problems on the network cause the BBC Master to wait indefinitely or for a very long period after a reset, just displaying "Acorn MOS" and nothing else. If this happens, check the following:

1. Ensure the terminators are present, switched on if necessary, and working.

2. Check that none of the other stations have the Econet lead plugged into the cassette port.

3. Try altering the clock speed a fraction.

Jumbled Output

The BBC Model B appears to be susceptible to muddling the output on screen (e.g. the result of a *. command etc) if the clock speed is just a little bit too fast. Try slowing the clock down a fraction.

"No Clock" error

When you get a No Clock error, first establish whether this is confined to a single station or a general problem.

If it is a general problem, check the following:

1. Make sure the Clock is connected to the mains and switched on. An Acorn Level 1 Clock needs an 8V power supply. The Level 3 Clock needs a 12V supply and the SJ Research Clock comes with its own power transformer and SHOULD NOT be used with anything else.

2. Check that the clock is connected to the network. Try replacing the Econet leads connecting the clock to the network with known good leads. Try connecting the clock to different network sockets.

3. Check that the clock link settings are not incorrect. In the Acorn level 1 clock, make sure there is a link jumper present selecting one of the speed settings. For the level 3 clock, make sure that there is a link jumper present at LK1 and make sure that a link jumper is present for at least one of links LK2, LK3, LK4 and LK5.

4. For an SJ Research clock, make sure an illegal clock setting has not been selected, ie. be certain that the Mark is less than the Period.

5. Make sure that the clock speed is not too fast or two slow for the network. If a fast speed has been selected, try slowing it down a fraction. If a slow speed has been selected, speed the clock up a little.

If the problem is isolated to one machine, check that the machine is connected to the network. Try connecting it to a different network outlet to make sure the socket box or T-piece is not faulty.

If the machine is a different type to the other machines on your network, try altering the clock speed a little to suit this machine.

"Line Jammed" error

If you get a line jammed error, this means that there is a constant signal on one of the network data lines. It could indicate a faulty Econet interface in one of your stations or a cross wire somewhere along the network cable.

Firstly, try switching off each station one by one and attempting to use the network from another station. This will help you to isolate an individual station at fault. Check the Econet interface is correctly installed in the suspect station.

If this does not resolve the problem, check the wiring of your network. Pay particular attention to the connections at socket boxes for signs that individual wires are touching each other or the boxes have been wired up incorrectly.

"Net error" error

A net error can result from a number of faults so check all of the following:

1. Make sure the clock is correctly set and that the speed is not too fast or too slow for the network you are trying to run.

2. Make sure there are not two or more stations on the Econet with the same station number.

3. Make sure there are no stations numbered 0 or 255.

4. Check the network cable wiring for crossed wires or bad connections.

Notify Test Programme

After carrying out the tests above, it is time to put your network into action to see if it really is working. As you may not have your file server running at this point, I have reproduced below my own version of the "notify" routine found in file server library directories. Don't worry about what it all means, there will be plenty of time for Econet programming later. For the time being, type out the programme below and try notifying one of your stations.

Note: when notifying to and from BBC Master stations, make sure you issue *UNPROT on both the sending and receiving station otherwise you will get a "not listening" error.

200REM (C) Ian Wolstenholme 2002
300REM Version 1.2 30/xii/2002
310REM Includes transmit polling;
320REM Not sure if this is necessary
400DIM osblock 255
500PRINT"Input station to notify ";
700PRINT'"Enter message"
930X%=osblock MOD256
940Y%=osblock DIV256
970ID$="--- "+STR$station+" --- "
990IFLENmessage$>msgspace message$=LEFT$(message$,msgspace)
1200osblock?2=0:REM net 0
1600X%=osblock MOD256
1700Y%=osblock DIV256
24300UNTIL(U% AND &8000)=0
24400success=(U% AND &FF00) DIV 256
24500IFsuccess=&40PRINT"Line jammed":ENDPROC
24550IFsuccess=&41PRINT"Not present":ENDPROC
24600IFsuccess=&42PRINT"Not listening":ENDPROC
24650IFsuccess=&43PRINT"No clock":ENDPROC
24700IFsuccess=&44PRINT"Bad transmit block":ENDPROC

If all is well, you should get a VDU 7 bleep on the remote station followed by the message you typed. If you get an error message then follow the troubleshooting suggestions above to resolve the problem. Don't forget to make sure you have typed the programme in correctly!

If you are really stuck, e-mail me.