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

Build your own Econet

Setting the Station Number

Each station on the network must have a unique station number. It is a one-byte number.

Certain station numbers have special meanings. 0 and 255 are reserved and must not be used. The network will not function correctly if computers with these station numbers try to access it.

254 is the default file server number to BBC Model B machines.

235 is the default printer server number to BBC Model B machines.

BBC Model B

The station number is set by way of a bank of links on the computer motherboard which are part of the BBC Model B Econet interface. They are located slightly to the left of the analogue port.

The top link is the least significant bit and the bottom link is the most significant bit. The links therefore have values of, from top to bottom, 1, 2, 4, 8, 16, 32, 64 and 128. When the link is present, that bit is clear. So, to set the station number to 128, for example, set all the links except the bottom link.

BBC Model B+

The BBC Model B + uses the same system except that the link values are in reverse order to the BBC Model B.

BBC Master 128

The Master 128 has the Econet station number stored in its CMOS RAM. It is the first byte of the CMOS RAM but this location is protected and cannot be set with a *CONFIGURE command.

It must be set using the *SET or *SETSTATION utility found on the network. If you can't get hold of this utility command, the following programme will get round the problem:

10REM Set Station Number
20REM BBC Master 128 only
30REM Version 1.0 28/xi/2003
40REM (C) Ian Wolstenholme 2003
50DIM stn 1
60PRINT'"Enter station number: ";:INPUT""n

Without going into too much detail, this programme communicates directly with the 6522 VIA and tells it to write the number you input into the first byte of CMOS RAM, which rather handily happens to be the Econet station number.

It can be used for all machines in the Master Series apart from the Master Compact.

If you don't fancy the typing, you can download the official utility here.

In the highly likely event that all the file attributes have been lost, the Set utility must be loaded in RAM and executed at &DD00.

BBC Master Compact

The Econet station number location is again protected in the Master Compact but the configuration settings are held in EEPROM not CMOS RAM so a completely different method has to be used. For the time being you will have to download the *SET network utility above. I must try to remember to have a look into this the next time I have a session with my Compacts so I can work out the code to set the station number and put a type-in listing here.

Other Station Number Settings

On the BBC Model B, the network will automatically look for a fileserver at station number 254 and a printer server at station number 235 unless you tell it otherwise (by specifying the file server station number in the *I AM command and by using *PS to set the printer server station number).

I can make you a bespoke version of the DNFS ROM with your own choice of FS and PS station numbers - see here for ordering details.

On Master Series machines, these can be configured.

*CONFIGURE FS <number> will set the default file server number.

*CONFIGURE PS <number> will set the default printer server number.

32-bit Station Number Setting

RISC-OS programming is beyond me, so it's not likely that I will be able to publish a type-in listing of how to change the Archimedes station number. However, I do have the SetStation utility, version 2.03, available for download here.

In the highly likely event that the file attributes have been lost, you will need to set the file type to UTILITY.