Prizm VTX5000 User to User software operating instructions. 1. Introduction 1.1 This software is compatible for 16k or 48k Spectrums. 1.2 Messages can be compiled off-line for later transmission or entered while on line. The screen will display the transmitted message. Programs can also be sent in BASIC or machine code, the latter being a specified block of memory, so allowing for files etc, to be transferred if required. 1.3 All these facilities are available via menu-driven routines which make the user to user software easy to use. Border colour is used to indicate whether the terminal is in Transmit or Receive mode, although a colour display is not essential 2. Setting up the software 2.1 You should set up your Spectrum, TV VTX 5000 and Program recorder (if required) as if preparing to go online. The VTX 5000 Mode switch must be in its central position TX' and no other software should be running. 2.2 Switch the VTX 5000 off-line. In addition, you must connect a suitable cassette recorder, as detailed in the Spectrum manual, to your micro-computer EAR socket to be able to load the software from the cassette supplied. This should be done on each system wishing to communicate with each other. 2.3 When the 'Micronet 800' display appears at switch-on, press a key to get the 'Main Micronet Menu' page, then press 7 to enter BASIC. Type LOAD"" then Enter. When the software has loaded successfully, the USER TO USER TERMINAL main menu page will be displayed, and you are ready to call your contact 3. Establishing a call 3.1 Dial your contact in the normal way and make sure thereis a good line established between both parties and that you can hear each other talking satisfactorily 3.2 Once the connection appears satisfactory, you must decide who is to tramsmit first Whoever decides to transmit first must press key 1 on the menu after going on-line and the other contact must press key 2 on the menu. To go on-line. both parties switch their VTX 5000 to the down position (silver switch) and replace their telephone handsets. From this point on all communications can be performed through the user to user software. If there are any problems whereby you think that you are not contacting the other party lift the telephone handset up, switch the VTX 5000 switch off line (up position) and talk to your contact to decide what problems you might be having and then restart the procedure again. 3.3 When clearing a call at the end of the session, it is recommended that you switch the VTX 5000 off line. 4. Available Functions 4.1 Transmit (Key 1). Border colour is Red. Messages typed on the screen by one person will appear on the other screen at the same time for the other person. When you have completed sending your message press the Symbol Shift E key and that will send an "end of message" statement to your contact. This will let your contact know that you have finished sending a message and it will automatically turn your screen to receive mode. At the same time, when your contact receives the "end of message" statement on the screen it will let them know that you are finished sending and it is their turn to send a message back to you. It will turn your contacts screen into transmit mode automatically and your contact is now ready to send a message to you. This is why it is very important to press the Symbol Shift E key every time either contact is finished sending their message. 4.2 Receive (Key 2). Border colour is Green. Messages typed on the screen by your contact will be received on your screen at the same time as your contact is typing. When your contact is finished typing the message, your contact will send an "end of message" statement and your screen will automatically be turned into transmit mode. (Border colour is red). You are now ready to send a message to them (Don't forget your "end of message" statement when finished.) 4.3 Compile message (Key 3). To compile a message on your screen before sending the message to your contact, return to the main menu by pressing Symbol Shift A. Select number 3 on your menu (Compile Message) and then typ< your message. After you type your message, pressSymbol Shift A to return to the main menu, Select 1 on the menu, (Transmit Message) then press Symbol Shift S (To Send A Compiled Message) and your message is then transmitted to your contact. You can see on the screen that the message is being sent and when the message is finished, press Symbol Shift E to send the "end of message" statement. This feature in the software is used when you want to compile a message to a contact prior to contacting the other party by telephone. (Whoever uses this feature must be in transmit mode (border colour red) and your contact must be in the receive mode (border colour green). 4.4 Send BASIC Program (Key 4). Border colour is red. The message CONTINUE Y/N is displayed at the top of the screen. Pressing Y causes the transmission sequence to begin When the sequence is completed correctly, the display reverts to the receive mode. If the border colour changes green and stays so for more than 15 seconds, transferrence has failed for some reason and the sequence should be repeated (Press SPACE to return to menu). 4.5 Send Machine Code Program (Key 5). Border colour is red. Start address/end address are in decimal; you must enter 5 digits in each case Forbidden areas are 28000 - 32000 on 16k version and 60000 - 64000 on 48k version Since the terminal software itself resides here. 4.6 Return to BASIC (Key 6). Programs may be listed or run in the usual way. To return to the menu page key: RANDOMIZE USR 28000 on 16k version RANDOMIZE USR 60000 on 48k version 5. Technical format 5.1 Data transmission: 8 bit data (even parity) Data rate: 1200 Baud (Half Duplex CCITT V23) Turn around code: Two consecutive 1B hex (ESC) characters 5.2 Program code: Incoming programs prefixed by 7,7,7then F7 H for machine code 7F Hex for Basic program Error Detection: Data is transferred in 256 Byte blocks. EXOR checksum is transmitted and verified at the receive end, which in turn sends back a status byte either re-transmit or continue with the next block Retrys: 3 6. Special messages that can be sent to your contact:Symbol Shift D: Transmit "Please pick up your phone"Symbol Shift E: Transmit "End of message" Symbol Shift F: Transmit "Please repeat"