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- Description of TTY Program
- TTY requires advanced basic 1.1, communications adapter,
- and 80 character wide screen.
- Comm adapter pins used are (2) xmit data, (3) rcv data, and (4) RTS.
- RTS is active (plus) when the program is in transmit mode, and may
- be used to control t/r switching in the TU or transceiver.
- TTY transmits and receives 5 bit teleprinter code (murray/baudot)
- at 45.45 baud (60 wpm) in half duplex mode and is intended for use
- in the amateur radio service.
- This documentation assumes the reader is familiar with amateur radio
- teleprinter conventions and practices.
- CAUTION: The IBM PC comm adapter uses rs 232 input and output voltage
- levels of +12v/-12v. Most commercial TUs use TTL levels 0v/+5v.
- Conversion circuitry may be required.
-
- The TTY menu provides for selection of receive or transmit mode.
- Switching between transmit and receive modes is done by calling the
- menu, using the F10 key.
- In receive mode, the normal mode of operation is to ignore incoming
- cr and lf characters, and print full lines of 80 characters to the
- display and printer. However, the F1 key may be used to select a mode
- of operation in which cr/lf characters are recognized, and normal
- teleprinter operation is simulated. F1 toggles this function on/off.
- F2 toggles the PC line printer on/off.The printer is used in receive
- mode only.
- In receive mode, the program is arranged for "unshift" on space,
- cr and lf, as well as "ltrs".
-
- In transmit mode, ltrs and figs shift characters are inserted
- where needed by the program.Ltrs and figs cannot be sent directly
- from the keyboard. The ascii cr (enter) key sends a cr/lf/ltrs
- sequence.The program assumes that the receiving terminal is
- equipped with unshift on space, and inserts figs accordingly.
- F3,F4,F6,and F7 are used to send preprogrammed messages. These
- messages reside at lines 17000,18000, 20000,and 21000, and may
- readily be changed to meet the needs of your station.
- F5 sends the required Morse code station identifier. This subroutine
- starts at line 19060. Morse code is sent by calling dit, dah, and
- intercharacter space subroutines at 19500,19600,and 19700 in sequence.
- Change lines 19060 thru 19080 to send your callsign.
- The program will accept either upper case or lower case keyboard entry.
- Other ascii characters which have no equivalent in murray code are
- ignored.
-
- Hints and Kinks:
-
- The `ignore cr/lf' mode is very useful when receiving conditions are
- less than perfect, and produces much more reliable copy. However,if the
- chap on the other end wants to send you some teleprinter art, use the
- cr/lf `on' mode.
- If the other station is using a conventional teleprinter, his line
- length is probably 70 or 72 characters. TTY lets you send 80 character
- lines which will overprint at the other station. Be careful!
- In transmit mode, characters appear on the screen when they are sent
- to the output buffer. The screen may be up to 128 characters ahead of
- the comm adapter output! F5 or F10 (cwid or return to menu) are stored
- and do not take effect until the buffer is empty. Hence the program
- may appear to `hang' while the buffer is emptying. Be patient! If it
- didn't work this way, some of your deathless prose would be lost down
- the bit bucket!
- 73 es GL de Bob Johnson AA4L, 11305 Rums Hill, Raleigh NC 27614
- phone 919 847 5606
-
- tty /murray Version 2.0 1/29/83
- The program has been entirely rewritten to improve readability
- and modularity. There are some significant functional changes:
- `75 speed' and `100 speed' capability have been added. It is no longer
- necessary to return to the menu to switch from receive to transmit and
- vice-versa. The `CQ', `de', and `test' messages are still embedded in
- the program code. However, in transmit mode, F1, F2, or F3 now cause
- the program to read files named msg1, msg2, or msg3 from disk. These
- files are then transmitted as text. This provides greater flexibility.
- Version 1.0 outputted the cw id characters on the rs-232 transmit data
- line. Due to some changes in station hardware at AA4L, cw id is now
- keyed by means of the cassette tape motor control relay. Also, PC
- generated sidetone is now audible through the system unit speaker.
-
- It developed that Version 1.0 had a bug which could cause a system
- crash. BASIC does not have provision to set the baud rate to 45.45.
- Hence the speed change is accomplished by OUT commands to &h3f8 and
- &h3f9. If a comm adapter interrupt occurs simultaneously with these
- OUT instructions, a system crash can occur. This has been corrected in
- Version 2.0 by the use of additional OUT instructions to disable the
- comm adapter interrupts.
-
- The embedded messages which you may wish to change to fit your station
- are now at lines 16300, 16400, and 16500. The `dit' subroutine is at
- 18500, the `dah' at 18600, and the intercharacter space at 18700.
- Change the gosubs following 18000 to call the dits, dahs and spaces
- in the proper order to send your call. The msg1, msg2, and msg3 text
- files are prepared using edlin or your text editor.
-
- NOTE: In transmit mode, use the <\> (backslash) to send the tty
- <BELL> character.
-
-
- Version 2.1 - 02/05/83
- A type-in message buffer has been added.
- THERE ARE NO PROMPTS TO EXPLAIN THIS FEATURE DURING PROGRAM RUN!!
- When the program is in "receive" mode, you may type into the
- fifty line buffer. Be sure to end each line with a <cr>.
- You may enter text into the buffer at the same time that characters
- are being received from the comm adapter.
- You cannot correct or edit what you have typed.
- What you type will appear, line by line, on screen line 25,
- replacing the receive mode prompts. After entering "transmit"
- mode, you may transmit this buffer at any time by pressing key
- <F9>.The buffer is effectively erased after transmission.
-
- version 2.2 - 02/14/83
- 110 baud ascii capability has been added.
- At the function menu, choice <4> will chain the program "asctty".
- The protocols are 7 data bits, space parity, two stop bits.
-
- GL de AA4L
- 9/29/83 -- Note that changes in the FCC regs have eliminated the
- requirement for cw identification. You may wish to delete the CWID
- routine, as it is no longer needed. This is easiest done by changing
- line 16600 to GOTO 15080. Do this in both tty22.bas and asctty.bas.