Tonto has been discontinued from the BT portfolio for some years but had remained a maintainable item until withdrawal on February lst 1993.

Tonto was an information terminal consisting of an integrated telephone workstation microcomputer with 1 or 2 exchange lines or PBX extension access. It consisted of a VDU monitor (colour or monochrome) and a telephone/keyboard base unit. The microcomputer had 128k RAM and used two microdrives for backup storage.
Rompacks were available which enabled additional software packages to be added, consisting of, VT-Link, Datalink Messaging and Interfile. A Data Comms Adaptor, dot matrix and daisy wheel printer were available for connection to Tonto.

Made by ICL Ltd. (Sold by ICL as One per Desk)

Tontos were withdrawn as a maintainable instrument with effect from February 1st 1993. They were not recovered from customers premises. Customers with maintenance or rental agreements were contacted and advised they could regard the unit as their own and could use it whilst it remains serviceable. If a Tonto is found to be faulty and affecting the BT line, the procedure to be followed would be the same as for any other customer owned equipment.

The Merlin Tonto is a revolutionary new customer terminal which combines, for the first time in a British Telecom (BT) product, the well-established principles of telephony with the developing technology of personal computers; together they make an unbeatable combination. The concept of the convergence of voice services, data services and computing is a cornerstone in BT's drive towards comprehensive office automation; many of the switch and modem products are now supporting this approach, and Tonto is the first customer terminal to do so.

The Merlin Tonto is the result of a co-operative venture between BT and International Computers Ltd. (ICL), together with Sinclair Research Ltd. The concept was first conceived in 1983, when BT was looking into the possibility of marketing an intelligent telephone/workstation. The Sinclair QL computer was being developed at this time, and seemed to offer BT some interesting possibilities, with the QL's advanced central processor and unique Microdrive storage units. ICL was also investigating this field, and had established valuable contacts with Sinclair. It thus seemed natural for BT and ICL to come together in a collaborative venture. The extent to which BT contributed to the development of the Tonto hardware and software has never been fully documented, because the project was, naturally, kept secret in the early stages and, later, BT was prohibited from disclosing details because the launch of ICL's version of the product `One Per Desk' coincided with BT's flotation on the stock-market. Suffice it to say that BT engineers made a most valuable contribution over a period of two years, and this is fully recognised by ICL.

As stated above, Tonto is very loosely based on the QL computer; it inherits much of the basic hardware and the Microdrives of the QL, but the software is entirely new. The two main system elements are a base unit containing the processor, memory, keyboard and Microdrives, and a monitor (black-and-white or colour) containing the display screen and the power supply. Plugged into the base unit are the telephony module (serving two independent telephone lines and a data modem) and the program expansion unit (the ROMpack) housing the optional XCHANGE business applications software. Additional programs supplied as capsules can be plugged into the ROMpack to increase Tonto's flexibility and usefulness. A printer (either dot-matrix or daisy-wheel) can be plugged into the back of the base unit.

At the heart of Tonto is an advanced microprocessor, the Motorola MC68008, running at 7.5 Mhz. The processor handles 32 bit words internally, but accesses memory in 8 bit bytes. The operating system and associated utility programs are held in 128 Kbyte of read-only memory (ROM), and, if the XCHANGE software is fitted, this is held in a further 144 Kbyte of ROM. The standard Tonto has 128 Kbyte of random access memory (RAM), and, to ensure that certain vital system parameters are not lost in the event of a mains power failure, a further 2 Kbyte of battery-backed RAM is provided. Three uncommitted-logic arrays (ULAS) are used to control the RAM and to drive the display and Microdrives. The telephony module has a processor of its own, the Intel 8051. The program for the telephony processor is held in ROM within the processor chip, which also contains a small amount of RAM for working storage. Communication with the main processor is via a serial link. The main processor instructs the telephony processor to carry out a function and then proceeds with its own work; when the telephony processor has carried out the command, it interrupts the main processor to give the result.
Data storage on the standard Tonto is provided by two Microdrive units. Microdrive cartridges contain 500 em of video quality magnetic tape, 6mm wide, driven in an endless loop at 70 cm/s. Data is recorded on two tracks, and each cartridge holds up to 100 Kbyte of formatted data. The screen display with Tonto can be either a 9 inch monochrome or a 14 inch colour monitor; in each case, the elemental resolution of the screen is 512 pixels horizontally by 256 pixels vertically. In this mode, four shadings (black, red, green and white, or the equivalent grey scale) can be displayed. It is also possible to switch to a 256 X 256 pixel mode, where eight shadings (black, blue, red, magenta, green, cyan, yellow, white) plus 'flashing' can be displayed. The bottom area of the screen is used by Tonto to show date and time information etc., and the extreme edges are not used (to improve image sharpness); the effective resolution available to programs is therefore 480 X 240 pixels.

The programs that a user would need to control Tonto are located in ROM, and are thus available immediately upon power-up. As on any personal computer, these programs are controlled by an operating system; the difference in the case of Tonto is that the operating system is fully multi-tasking; that is, several programs doing different jobs can be run apparently at the same time. For example, this enables Tonto to receive an incoming electronic mail message while it is loading data from Microdrive, carrying out a spreadsheet calculation, controlling a telephone call, and, all the time, keeping the clock up-to-date. Changing from one application to another is achieved with at most two keystrokes. Access to programs is by menus; options at a given level are presented to the user as a numbered list, and are entered by the appropriate number being typed. Once entered, programs are controlled by the use of function keys whose use is prompted by 'footnotes' at the bottom of the screen display. The whole system has been designed to be as user friendly as possible so that even a beginner can make good use of Tonto straightaway.
Extra applications programs can either be loaded from cartridge, or supplied as program capsules which plug into the ROMpack. Alternatively, users can write programs in the BASIC programming language for one-off problems; these can be presented as applications, or loaded while BASIC is being run.

Tonto is designed to help improve the way people work. Many things that formerly required paper records and manual methods can now be handed over to Tonto. The best way to consider Tontos capabilities is to divide them into a number of categories, as below:

Tonto as a Sophisticated Featurephone
Tonto provides a personal telephone directory with full editing features, and permits calling by short code or by searching on keywords. Once a telephone number has been found, the user has the benefit of hands-free dialling and the repeat last number and re-dial one of the last six numbers facilities. Dialling is by means of press-buttons, and offers multi-frequency or loop-disconnect operation, with full PABX recall capability.
Tonto gives the user independent use of two telephone lines, each of which can be used for either voice or data communications. When a line is in use for a voice call, the call can be put on HOLD (so that the distant party cannot overhear conversations at the caller's end), and a second incoming call can be answered without the first being lost. If two voice calls are in progress, the user can shuttle between them to carry on two conversations.
A call-timing facility with automatic totalisation in each of BT's charging categories is also provided. The charging category to be used for a particular call can either be contained in the directory entry for that number, or entered by the user when the call is made. When call timing is in operation, the duration and cost of the call are continuously displayed on the screen.
If the user is not available, Tonto can answer the call by using a voice synthesiser. The message can vary according to the time of day, and is constructed by the user from a fixed repertoire of words.

Tonto as an Advanced Massaging Terminal
Users can send desk-to-desk text messages, with T-Link error-corrected transmission. A full on-screen editor enables messages or notes to be composed in the user's notepad. Messages are automatically sent (using short codes) from the users 'out-tray', to multiple addresses if desired, and are received, unattended, in the user's 'in-tray'. If any message should fail to be sent, owing to machine or network problems, it is automatically retried up to six further times.

Tonto as a Versatile Bureau and Computer Access Terminal
When a distant computer is accessed over the telephone network, Tonto provides an integral modem operating at 300 baud full duplex or 1200/75 baud half duplex. Viewdata and basic teletype modes of operation are built-in, and an optional plug-in capsule provides DEC VT100/VT52 operation. BT's Data Communications Adaptor enables Tonto to be connected directly to mainframe computers or local area networks at up to 9.6k baud. In all cases, connection to computer services is made simplicity itself by the use of short codes and programmable function keys for user identifications, passwords, etc. Tonto has a directory for storing computer service numbers, and a profile store for connection details (speed, parity, etc.) so that users have to enter details only once. There is also a page store for retaining information found while on-line. Optional software transfers this information to the XCHANGE suite for further processing, or to the electronic mail program for onward transmission.
The Data Communications Adaptor, or optional software on the standard Tonto, gives a both-way file-transfer capability. This can be used, for example, to transfer to Telecom Gold some text prepared off-line (thus saving connection charges) or to receive a telephone directory from a colleague

Tonto as a Powerful Personal and Business Computer
A very popular option for Tonto is the business applications suite XCHANGE. This consists of a word processor, a spreadsheet, a database manager and a business graphics package. Comprehensive facilities are available that enable data to be transferred between applications, so that, for example, users can see, displayed as a graph, sales figures that have been calculated in a spreadsheet. The BASIC programming language, featuring full window-based commands, is provided as standard, and there is a four-function calculator with memory and percentage operations which uses a full-screen display. Extras now available from third-party suppliers are an action diary, a project management system and spreadsheet template software; to enhance the memory, optional twin 3 and half inch 720 Kbyte disc drives, and the 128 Kbyte memory expansion unit are also available. Program development facilities are available for writing third-party applications in 'C', Microsoft-compatible BASIC or 68000 Assembler.

Merlin Tonto is a registered trademark of British Telecommunications plc.
QL and Microdrive are registered trademarks of Sinclair Research Ltd.
XCHANGE is a registered trademark of Psion Software.
One Per Desk is a registered trademark of International Computers Ltd.
T-Link is BT's brand name for the Networking Protocol from Microcom Inc.
VT is a trademark of the Digital Equipment Corporation, Maynard, Massachusetts, USA.

Overview of Facilities.
Tonto is a powerful easy to use Personal Information Centre that integrates communication and facilities. It is suitable for both business and home use, and has the capability of carrying out a variety of tasks which would normally require several pieces of equipment. Its main features are as follows:

Comprehensive Telephone Facilities.
These include Telephone and Computer Directories, Abbreviated Dialling; Last number redial; Automatic Answering with electronic voice; user programmed call timing and charging facilities; call monitor loudspeaker.

A 128K Ram Personal Computer.
This consists of keyboard, black and white or colour display and two microdrives for storage. The BASIC programming language and a calculator are provided and a set of four business application packages known as Xchange can be added.

An Information Access Terminal.
Tonto provides the equipment necessary for the connection to, and use of, information and mailbox services such as Prestel and Telecom Gold.

A Data Communication Terminal.
Data can be exchanged with other Tonto users or larger computers. An Electronic Messaging Terminal.
A Messaging application package utilizes the data communication facility of Tonto. This enables the user to automatically send typed messages over the telephone line and receive typed messages from other Tonto users.

To increase Tontos' flexibility still further, a second telephone line can be connected and a printer added.

When equipped with 2 telephone lines it is possible to:
Make a voice call on one line whilst simultaneously sending or receiving data on the other. Two data calls cannot be made at the same time as there is only one modem.

Conduct 2 voice calls. One call will have to be on hold since there is only one handset. A 'Hold-Shuttle, key is provided to enable ease of switching from one call to the other.

When equipped with two lines Tonto always selects line 1 for an outgoing voice call, or answers line one first when both lines are ringing. outgoing voice calls are automatically routed to the 'other, line if one is busy. Normally line 1 is used as the 'voice line, because line 2 which is equipped with a modem must be used for data, calls.
When Tonto is equipped with a single telephone line it will be used for both voice and data calls. To ensure that an emergency call can be made, any outgoing data call will be stopped immediately the handset is lifted.
Whether equipped with one or two lines a 9 volt battery maintains telephone service on line 1 in the event of mains failure.

Tonto operates as an advanced push button telephone using the key pad to the right of the main keyboard. one or two lines may be used and these may be direct exchange lines or extension lines from a PABX. Each line has a lamp which is lit to indicate when it is busy, the lamp flashing for an incoming call. The unit can provide loop disconnect or multi-frequency dialling. Earth recall facility for PABXs is also available.
A monitor loudspeaker with volume control is provided so that calls being set up can be monitored without the need to lift the handset. Full loudspeaking telephone facilities are not however available. Incoming calls are announced by a tone from the loudspeaker.

Last number re-dialling is available by pressing the RED1AL key. A screen display of the last six numbers dialled is also available and, if required, any of them redialled by pressing two keys.

An estimate of the cost of a call may displayed on the screen but necessitates the selection of the appropriate charge rate stored in memory.

Telephone Directory
As well as making calls from the key pad or using the number redial facility, any number held in the created directory may be dialled automatically. The directory is capable of holding in excess of 300 hundred entries, with each entry identified by a nominated 3 character code. If after lifting handset or pressing SPKR key the code is typed, the number is automatically dialled.

The contents of the directory can be saved onto a microdrive cartridge to prevent loss of the directory if the power supply to the Tonto should fail.
A similar directory can be established as a computer services directory, for example for access to Prestel, allowing short code automatic 'dial up, facilities.

Auto Answer
When Tonto is unattended calls may be answered automatically. A pre-set message is spoken by a synthesised voice. Up to 16 messages may be composed from a standard vocabulary of 200 words and numbers. The unit is then programmed to use one of the messages as required.

Power Fail
If for any reason the mains power supply to the Tonto fails, calls may still made and received. This is achieved via a small, replaceable, 9 volt battery within the unit. During this time, incoming calls are indicated by a buzzer.

Text Messaging Terminal
Text messages may be sent from one Tonto to another Tonto via one of the telephone lines. Messaging can be used for much of the correspondence sent in and out of an office, for example telexes, memos, letters, agendas etc.. It can be useful as a back up to the telephone enabling you to confirm the contents of a call or leave a message for someone who has not answered the phone.

The messaging system has been logically arranged into a 'notepad', an 'in tray' and an 'out tray'.

Using the "notepad" option, the message is first composed on the screen using the main keyboard. It may be up to 2 pages long. It may be edited and corrected to obtain a polished result. The message is then addressed to the potential recipient by adding the telephone number of his Tonto. Where the receiving Tonto has two lines the line receiving data must be given. The senders name and details are added automatically providing the customer sets the
default data.
The completed message is now placed in the "out tray". It will be sent automatically as soon as possible but with a copy retained in the 'out tray' for reference. If it is not possible to send the message an indication is given on the screen.

The 'notepad' can also be used to create and store notes that are not intended to be sent immediately but which may be required later.

Incoming messages are stored in the "in tray" and the presence of their arrival indicated on the screen.
The contents of the "trays" and "notepad' can be printed out and for added security, saved on the one of the Tonto microdrive cartridges.

Personal Computer
Tonto operates as a personal computer with 128 kbytes of Random Access Memory (RAM) and 128 kbytes of Read Only Memory. The ROM available is further increased by fitting a plug in unit known as a "Rompack" which will accommodate 2 or 4 Romcapsules.

Storage is provided by the two microdrives. Each microdrive cartridge contains an endless loop of tape with a capacity of approximately 100 kbytes.

Tonto is provided with a Basic "interpreter" which enables programs written in Basic to run on the machine. (Basic is a popular programming language. The "interpreter" converts these Basic commands into a language that Tonto understands.) Thus with the 'interpreter, program loaded from a microdrive cartridge Basic programs may then be typed in or loaded from cartridge.

More advanced programs are contained in Rompack and Romcapsule form, for example Xchange.

M1811 Xchange Rompack
Xchange is an optional business applications package of the following 4 elements, QUILL, ABACUS, ARCHIVE and EASEL. The package has the advantage that all elements are available simultaneously therefore information may be interchanged between elements. The function of each element is as follows,

QUILL - An easy to use word processor.

ABACUS - A spreadsheet that simulates a large sheet of paper on which figures and words may be entered in rows and columns. It is ideal for monthly accounts, sales forecasts, balance sheets etc..

ARCHIVE - The data base acts like a very large and flexible card index system suitable for the storage and manipulation of records. Full facilities are provided for searching the records for individual items of information.

EASEL - Provides business graphics and has been designed for the easy production of of well presented graphs and charts for incorporation in, for example, management papers and reports. Available presentation includes line graphs, pie charts and bar charts.

M1813 Xchange Rompack
Has the same function as the M1811 but has 4 slots and the later version 2.5 Xchange.

Tonto also incorporates a calculator, with the facilities of a simple pocket calculator but with the advantage of a large display screen and 16 digit display.

Addition, subtraction, multiplication and division are provided together with percentages and a single memory store.

Viewdata and Computer Terminal
Viewdata Terminal

Tonto provides the facilities of a viewdata terminal suitable for gaining access to Prestel and other compatible viewdata systems. The dialling up and logging on procedures are completed automatically using the information contained in the Computer Services Directory.

Complete Prestel pages can be reproduced on the screen. If the information on a particular page is likely to be required again that page can be stored in the Tonto memory and reproduced later without the need to access the Prestel computer again.

Individual pages can be printed out on the Tonto printer providing a 'hard copy, for future reference.

Computer Terminal
Tonto can be used as a terminal to access a mainframe computer. This type of operation is known as "glass teletype" because Tonto acts as a standard teletype terminal except that the information is displayed on the screen rather than printed out.

This facility gives Tonto access to Telecom Gold, BTs computer based electronic "mail box" service. Using the Data Services Directory the Tonto user can automatically dial up Telecom Gold's computer to check whether any messages have been sent to his "mail box" or to type a message to the "mail box" of another person. Messages can be printed out if required.

Optional Applications M1825 VT Link Capsule
The VT Link capsule acts as an interface to allow "dial up" access to a wider range of computers than that provided by the basic Tonto alone. It emulates the characteristics of of the Digital Equipment Corporation DEC VT100 and VT52 video terminals. once the capsule is plugged in you can communicate with a DEC computer and other computers that use the DEC VT52 and VT100 standard Communication is also available to other computers by using protocol converters that accept VT100 or VT52 format.

M1887 Data Comms Adapter
Provides a similar function to the VT link except that it is designed for direct (wired) connection between the Tonto and an adjacent host computer or for access to a data network. It permanently connects to the Tonto via one input socket of the Rompack.

M1822 MAP2 - Advanced Messaging
Advanced Messaging, whilst being fully compatible with the initial version of massaging, offers a number of improved features. These are:-
1. Multiple addressing - With this feature the user can specify a list of destinations rather than one single destination.
2. Automatic retransmission - In the case of failure to successfully transmit a message, automatic retransmission is performed with up to a maximum of six attempted transmissions.
3. Export and Import of Messages - Having received a message, the user is able to export the message onto microdrive. From there the message can be imported into Quill and form part of the users document. Conversely, the user can import a document prepared in Quill and send it as a message.

The following is the full list of Tonto spares. They should be retained in the packaging supplied by the manufacturer and that packaging must be used when returning faulty items for repair via Section Stock. Faulty Monitors and Rompacks should always be returned as complete assemblies with covers. Faulty processor and. Telephony PCB's must be returned without covers. Printers should not be repaired on site, and faulty printers should be returned to repair centres as complete units. Customers should be charged for covers that have to be changed due to damage using per occasion charging procedures. All faulty equipment must be accompanied by a completed A8807A

Tonto items and their codes.

Main Modules
MOA M1800 Processor PCB 98 3063
MOA M1800 Keyboard Sub assembly 98 3064
MOA M1800 Microdrive assembly 98 3090
MOA M1800 Telephony PCB 98 3065
MOA M1800 Monitor (Complete) 98 3093
MOA M1885 Colour Monitor 98 3103
MOA MP1711 Printer 1A (M1880 Dot Matrix) 98 1691
MOA MP1713 Printer 1A (Dot Matrix) 98 1823
MOA MP1881 Printer 1A (Daisy Wheel) 98 1702
MOA MP1881 Tractor 1A (Tractor Feed) 98 1708
MOA MP1881 CSF 1A (Cut Sheet Feeder) 98 1709
MOA Cable I/F 15A (for MP1713 and MP1881) 98 9092
MOA M2105 Printer Ribbon (For MP1711 and MP1713) 98 1652
MOA MP1881 Ribbon 1A (X6) 98 1800
MOA MP1881 Daisy Wheel 1A 98 1802
MOA M1889 Printer Switch 98 3104
MOA M1800 Line Cord 98 3088
MOA M1800 Handset and cord 98 3087
MOA M1887 Data Comms Adaptor 98 3096
Software Packages
MOA M1810 Rompack 98 3051
MOA M1811 Rompack (with Xchange) 98 3053
MOA M1813 Xchange Rompack (4 slots) 98 3113
MOA M1821 Messaging Package 98 3057
MOA M1822 MAP2 Advance Messaging Package 98 3114
MOA M1823 Interfile Package 98 3115
MOA M1824 DataLink Package 98 3116
MOA M1825 VT-Link 98 3105
MOA M1850 Welcome Cartridge 98 3058
MOA M1851 BASIC Cartridge 98 3059
MOA M1853 Xchange Demo Cartridge 98 3061
MOA M1854 Xchange Help Cartridge 98 3062
MOA MP1881 Configurator Cartridge 98 3121
MOA MP1881 + CSF Configurator Cartridge 98 3122


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Last revised: December 19, 2010