The envelope landed on my desk with a thump. "It's the new Electron communications package from Pace," panted the managing director, tired from carrying the money to the bank, "we need a review, quick".

"Is there a manual?" I asked stupidly. "Of course there isn't. A manual indeed. You'll be wanting your wages next," came the reply as he headed back to the vaults.

Odious toad. I know for a fact he goes to bed with the Advanced User Guide each night. That's why he always looks so tired in the morning.

However, we Peters like a challenge, and the result is this review of Tellstar, the fascinating combination of RS423 interface and communications software from Pace.

On opening the envelope I found a neat black plastic box, obviously destined for one of the slots in the Plus 1.

Coming from it was a black lead with a DIN plug (like the one on the cassette lead) at the end. And since Tellstar is a communications package it didn't take me long to figure out that it was an RS423 lead, the bit that goes into a modem.

So... I fitted the cartridge into one of the Plus 1 slots, put the lead into the modem, switched on and got... nothing. Well, that's not actually true. What I did get was the:

%

sign that showed me that the Electron still had the Pascal cartridge fitted.

Now it was a safe bet that inside the Tellstar cartridge there was a ROM containing software. The problem was to get at it. To use Pascal or View you just use a star command as in:

*PASCAL

or:

*VIEW

So I was certain that what I needed to invoke Tellstar was a star command, but star what? Well: *what? didn't work, and neither did any others. I just sat there gazing blankly at the screen (I spend a lot of time doing that!) until inspiration dawned.

Tellstar is a communications package produced by Pace. And Pace produce another communications package, Commstar, for the BBC Micro. You get into Commstar with:

C

so why not try that out on the Electron?

I did... and lo and behold, it worked, which was wonderful for three reasons. The first is that, if it hadn't, you wouldn't be reading this enlightening review.

The second is that I was fairly familiar with Commstar - it's the standard communications software many of us use - and the opening menu of Tellstar was a dead ringer for Commstar's first page.

And the third was I had a manual for Commstar and, with a bit of luck, Tellstar wouldn't be too different.

The result was I was able to explore one of the most exciting pieces of Electron software to come my way in a long time. Without, I may add, the aid of a manual or a safety net.

Tellstar provides Electron users with two things. The first is an RS423 interface, the second is the software to use this interface in conjunction with a modern (of which more later) to talk to other computers in a number of different ways.

If RS423 looks familiar, it's because the Plus 1 start up message tells you that it's got an RS423 even when it hasn't.

The story goes that the guy who wrote the software for the Plus 1 was told that it would have an RS423 built in while the guy who did the hardware wasn't informed of this.

Whatever the truth of the tale, now, at last, you can attach one to your Electron. But, having said that, what is it?

Put very simply, an RS423 interface is a device that allows information from a computer to be sent along a wire to another computer.

To go a little deeper into it, it converts data such as ASCII codes from the parallel 8-bit form used inside the micro to a serial form which can be sent bit by bit along a wire to another computer.

It also does the reverse job, taking serial information bit by bit from another computer and rearranging it into the 8 bit form that the Electron can use in its workings. Figure 1 shows this happening to the letter A.

Figure 1

Actually it's a lot more complicated than that. The data can be sent at different speeds along the wire - the baud rate - and the data itself can take different formats to meet different conditions, hence the terms such as word length, stop bit, start bit and parity that all communications freaks come to know and love.

Also, apart from the very simplest cases where you can just use a wire between two RS423 ports, you'll be using the telephone system to send and receive signals.

And to do this you need a modem, a device that takes the signal produced by the RS423 port and converts it to a form that can be sent long distances over the telephone network.

It also does the reverse, taking the signals from the phone line and turning them into a form the RS423 can use. Figure II shows how the micro, RS423 and modem work together.

Figure II

When you first enter the world of micro communications you'll come across a lot of jargon such as parity, protocols and baud rate.

I don't have room to go into them all in this article and really, there's no need ot, as it's all done for you with Tellstar.

The communications software is there to make life easy for you. When you first enter it, it's set up to default settings, which are the ones you will usually use. As you gain more experience and want to try different baud rates and so on, Tellstar allows you to change the settings using a simple-to-follow sequence of menu choices.

We'll come to some of the different settings later. First, let's take a look at some of Tellstar's uses and just mention the jargon as needed.

Since it's a communications package the obvious use of Tellstar is to communicate. But with what? Well you can communicate with other micros, bulletin boards, mainframes, databases, viewdata systems and all sorts of things.

Figure III shows some of the alternatives.

Figure III

Tellstar does all this communicating in two main emulations or modes. The first is terminal mode, a general-purpose mode which allows communication with all sorts of computers.

The second is the Prestel mode which turns the Electron into a Prestel terminal, allowing you to enter one of the largest Viewdata systems in the world.

When you start off,you're in terminal mode but you can change between the two modes at the touch of a button from the main menu. Figure III gives some ideas of the possibilities of each mode.

Since it's the default, let's explore at the terminal mode first and look at one of its simplest roles, the chat facility.

This allows you to phone another micro user and talk to him using the micro's keyboard. To do this, all you have to do is to press C to tell Tellstar that you want to talk or chat to someone.

You then phone the person up and, when they've picked up the receiver, switch in the modems to handle the signals and chat away. What you type in appears on the other micro's screen and vice versa.

Strangely enough, you won't see what you type in on your screen unless you press the E for Echo option, so it is mirrored or echoed back to your screen.

Of course, behind the scene, things are a little more complicated. For a start, both micros have to be using the same types of data packets, sent along the wire at the same speed.

In computerese, the two micros have to be configured so they can talk to each other. This includes various menu items such as XON/OFF and such matters as parity, stop bits and so on.

However the joy of Tellstar is that the default options (for the technical: 300/300 baud, 8 bit word with no parity and one stop bit) are perfectly adequate for chatting. That is, so long as both micros are set up, or configured, this way.

You don't have to concern yourself about the settings unless you want to. And when you do feel you know enough to experiment, Tellstar's system of menus makes changing the options simple.

Just chatting may seem a little daft. After all, you're linked by the phone, why not talk to each other? And, of course, that's right. But chatting has its value, as we'll see. A second use of the terminal mode is to send files from one computer to another, a procedure that Tellstar makes simple.

However when you're setting up to transfer files, it's always best to chat a little first to make sure that all the settings are all right and that the telephane connection is a good one.

Then, when you're satsfied, you can transfer the file from your micro to the other at the touch of a button. The file transfer method used by Tellstar will handle practically anything, programs, Mini Office files, data files, whatever. And, of course, you can receive files as well as send them.

It's a simple way of getting information from one micro to another. I've used Tellstar to send programs from my Electron to a BBC Micro 40 miles away. It certainly beats the post! And the other micro doesn't have to be an Electron or BBC Micro.

It can be any micro so long as the data it sends obey the same conventions as you are using. Having said that, unless the Basics are very similar, this tends to restrict you to machine code programs and ASCII files.

As I've mentioned, sending files is simple and you can do it at the default settings.

If you try altering any of the RS423's configurations - to speed things up or talk to another micro with different communications software - you might have to experiment for a while until both micros are correctly set up. This is where chatting comes into its own.

So far, our two uses of terminal mode have meant that we have to have a willing and cooperative partner in charge of the other micro.

A third use, however, allows Tellstar to go solo (well, almost). This is when it's used to talk to bulletin boards.

All a bulletin board is is a micro that's dedicated to running a special kind of communications software.

It has a modem that automatically answers calls, so to get on to a bulletin board all you do is ring up the number and, if the line's not engaged. you're on. That is, if you've got your Electron configured correctly.

In nearly all cases the bulletin boards will work at Tellstar's default settings, so getting on to a bulletin board is an easy way of starting your communications career.

The board acts as an electronic version of a noticeboard. Once on the board you can read messages, leave messages and even, in a few cases, download software into your micro for later use.

Bulletin boards have a fascination all of their own and can be addictive. Boards are springing up all over the country and abroad which you can contact with little or no trouble.

But beware, while the use of the boards is free, you're paying for the phone call and some of these boards are a long way away. It's decidedly a cheap rate operation.

The fourth use of terminal mode we'll look at is when it's used to talk to a mainframe computer.

If you want, you can look on this as a super bulletin board with lots more facilties such as sending messages to people's mail boxes via the mainframe, accessing huge databases and lots, lots more.

The drawback is that, unlike bulletin boards, they're not free. You usually have to be a subscriber before you learn the magic words that will allow you to use the mainframe's facilities.

However most subscriptions are remarkably cheap and, with some systems at least, you can often access the mainframe for the price of a local call, wherever it is.

So far I've only used Tellstar to access one such system, MicroLink, which is part of Telecom Gold. MicroLink has all sorts of facilities from electronic mail to free software, from a Teleflora service for sending flowers (honest!) to news pages.

It was simple to get on MicroLink using Tellstar, but it did involve me reconfiguring the RS423. And that was easier to do than to spell.

All I have to do was to select tha Initialise option from the main menu and then pick my new settings (gleaned from the MicroLink manual, which is one manual I do have) from those options offered me on a second menu.

Again, it was easier done than said. Once that was done I was back at the main menu. I then phoned up the computer on a local number even though it's miles away, selected chat mode - again at the touch of a key - and when it had answered and I identified myself, I was away.

As I said, all sorts of facilities are available on MicroLink but I normally stick to sending messages to other users via their mailboxes.

Now if I were resticted to just typing in my letters it would be a bit siow and the phone bill would mount up (Tellstar displays a little clock in the top right hand corner of the screen to remind you that tempus is fugitting away).

Here another aspect of terminal mode comes into play. This allows you to use either disc or tape to hold a file such as a letter.

Then, when you've got through to a mainframe and you want to send the file you can go back to the main menu (always available with the Escape) and call up the file at the touch of a key.

Alternatively you can load the file into the Electron's main memory, called a buffer for these purposes, and output from this when needed. It's a lot faster than typing.

You can also use the buffer or disc to store incoming files for viewing later when the phone bill isn't mounting. You can even get hard copy if you've got a printer.

Screen 6 shows a buffer full of MicroLink messages.

While it's one of those things that you may not see the point of at first, this use of disc and buffering gives Tellstar great flexibility and enhances its usefulness.

And that's where we come to the end of our discussion of terminal mode. We've seen four of its uses but, believe me, there are lots more.

However now it's time to turn to the second of Tellstar's modes, the Prestel one.

Prestel is another of British Telecom's computer systems, dedicated to providing a Viewdata service to users.

Basically, this means that it is a huge database full of "pages" of information which are displayed, upon request, a screenful at a time rather like the Ceefax or Oracle pages you'll see on your TV.

In Prestel's case, the information is coming over the telephone wires, not down the TV aerial, but the resulting screens look the same.

The big difference is that you can use the phone lines to interact with Prestel and obtain the screens you want without having to wait for them to cycle round.

Getting into Prestel via Tellstar is easy. You press P for Prestel at the main screen and you get another, similar, screen with Prestel Emulation written at the top.

You can now go into Prestel by dialling the computer running the gauntlet of its security checks - it's another subscription service - and you're away.

Selecting Prestel mode has taken care of all the settings automatically.

You're now free to explore Prestel which, as it's so huge, is a life-long task.

And considering that some of its sections are as user friendly as Attta the Hun, it's just as well that Tellstar's Prestel emulation sets up the function keys to do some very useful things.

The most useful of these is to "tag" a page. Once you've done this, you can retrieve that page from anywhere inside Prestel at the push of a function key.

In fact, you can have several tagged pages, all of which can be retrieved in order.

Take my advice and tag the main menu so you can always get back to it. In fact, at first if you see a menu, tag it. This will save much wailing and gnashing of teeth.

The next most useful function key is the one that sends a copy of the screen to your filing system. These screens can later be loaded into Tellstar's buffer and Viewed, saving telephone bills.

Other keys take you back to the previously accessed page, send Escape characters to Prestel - when you need to use it, you'll know why it's there - and to download software.

As yet there isn't any Electron software available on Prestel to download but I did try.

I entered the Micronet section of Prestel and downloaded a BBC Micro program successfully. However the program was one that wouldn't work on the Electron. Still, the downloading worked! It's a bit like saying the operation was a success but the patient died! However I have little doubt that soon Micronet will have software available for Electron users.

As I've said, Prestel isn't the easiest of systems to use, but having Tellstar makes things a lot easier.

Having said that, there is one small drawback to the Tellstar Prestel emulation. It's in black and white, not colour.

This is because the Electron doesn't have the BBC Micro's Mode 7 teletext graphics and so has to do the best it can. And, sadly, this won't stretch to colour.

I don't find this a drawback. After all, Electron users don't need the horrible garish colours used to satiate jaded BBC Micro users, do they?

Considering that Tellstar is the only communications package currently available for the machine, Election users could have found themselves with an inferior package, offered on a take it or leave it basis.

Happily this is not the case, and Pace has produced a first rate package, every bit as good as the BBC Commstar version, if less colourful.

Getting into communications can be difficult, but with its wise choice of default settings and its easy-to-use, menu-driven operation, Tellstar makes it as simple as possible.

Given this, and its flexibilty and wide scope, I have no hesitation in recommending Tellstar to any Electron user interested in communications - especially to those who know little or nothing about the subject.

In fact, with the way Electron prices have gone, I recommend the whole package - Electron, Plus 1 and Tellstar - to anyone who wants to join the telecommunications revolution.

It's a first rate package, powerful, versatile, yet straightforward.

In fact, considering the way it allows your Electron to access the outside world, it must be the ultimate Electron expansion.