April 22, 1981 The Terminal for the Apple ][ by Michael C. Koss Hardware requirement: 1) Apple ][ (at least 32K of memory) 2) Apple Communications Interface Card or D.C. Hayes Micromodem 3) Video monitor 4) [A modem will be needed if The Terminal is to be used to communicate over the telephone and the Apple Communications Interface Card is used] General description: The Terminal allows the Apple ][ to be used as a display terminal with some extended features not found in the ROM program resident on the interface card. o 32 line, 70 column full ASCII display o full ASCII "virtual" keyboard o menu oriented set-up of terminal parameters o interface card o baud rate o transmission protocol o card slot o full/half duplex o echo remote o key click o white/black background o auto line feed o wrap around o audio/visual bell o special display control sequences (similar to VT52) o relative and absolute cursor addressing o insert/delete line o insert/delete character --------------------------------------------------------------------- Using The Terminal Starting the program: Start the program by typing: >BRUN THE TERMINAL if the program is on disk. Otherwise, load the cassette: *800.1D00R *800G The Menu: The menu is your means of changing certain parameters that determine the operation of The Terminal. A number of param- eters are displayed with their current values. The cursor will appear between a parameter name and its current value. At this time, you can change the value of this parameter by pressing the ">" or "<" key. > The ">" makes the value of the current parameter the NEXT value in the list of possible parameter values. < The "<" makes the value of the current parameter the PREVIOUS value in the list of possible parameter values. So, you can look at each of the possible parameter values in turn by repeatedly pressing ">" or "<". To change the value of another parameter i.e., change the "current" parameter, press "." or ",". . The "." makes the current parameter be the next parameter in the menu. This will move the cursor to the next menu position. , The "," makes the current parameter be the previous parameter in the menu. This will move the cursor to the previous menu position. So, you can select each of the parameters in turn by repeat- edly pressing "." or ",". Once the parameter values are selected as desired, press the "ESC" key to exit the menu and run The Terminal. While in the menu, you can enter the Apple monitor program by typing (mnemonic for "quit"). You may then type to reenter The Terminal. Using the "virtual" keyboard: Because the Apple ][ keyboard does not allow all of the ASCII characters to be typed in directly, it is necessary to allow for some means of indicating these other characters. Alphabetic Case: When the program is started from the menu, the alpha- betic characters on the keyboard will represent the capital letters. To indicate that they are to repre- sent the lower case letters, type: &S Now, all alphabetic characters will be interpreted as lower case. To change the interpretation back to upper case, type: &C [These two "switches" are mnemonic for Small and Capital.] When only a temporary shifting of case is desired, (e.g., you are typing in lower case and you want the next character to be capitalized, but you want to continue to type in lower case afterward) you can type to shift the character immediately following while leaving the "default" case unchanged (note that can be easily typed by depres- sing the right arrow key on the Apple keyboard). Backspace/Rubout: When the program is started from the menu the back- arrow will represent the Rubout character [since the back-arrow is just another way of typing , then will also be interpreted as Rubout at this time]. If you want to switch the inter- pretation to be Backspace, then type: &B To switch back to the Rubout interpretation, type: &R Again, there is a way to type an isolated Backspace when Rubout is the default (and vice-versa). Type: & Other printing characters: Some characters which are not on the Apple ][ key- board can be indicated by typing another character preceded by "&". A table of these follows. Character not Character to be typed on keyboard after "&" to indicate it ------------------------------------------------ [ ( \ / ] ) _ - ` ' { < | ! } > ~ ^ break space & Note tha though it appears on the keyboard, since you must type "&&" to indicate it. Control Characters: The control characters, , through , and through can be indicated directly by holding down the "CTRL" key while pressing the corresponding character. To type a you must type "". Still, two ASCII codes are not represented. Again, indicate them by typing "&" and another key: ASCII code (HEX) Key following "&" ----------------------------------------- $1C L $1F O [two characters attainable normally from the Apple ][ keyboard but not explicitly mentioned above are $1D, and $1E, which can be typed as , and , respectively.] Additional functions for the D.C. Hayes Micromodem: When you are using the D.C. Hayes Micromodem, the program will start with the telephone line discon- nected ("on the hook"). To connect the telephone line, type: &P [which is mnemonic for "pick up"] To disconnect the telephone line, type: &H [mnemonic for "hang up"] You may also dial a number by typing: &D The program will respond with the message: TELEPHONE NUMBER: You can now type in the number to be dialed (using the back-arrow to correct mistakes, the number will not be dialed until you press ). Wherever you insert a slash ("/"), the computer will pause for one second before continuing with the rest of the number. This is to allow for pauses that may be necessary for the telephone equipment (e.g., you might type: 9//123-4567 to call the outside number 123-4567 if it takes about two seconds for the outside dial tone to appear after typing a "9"). Any other characters may be inserted into the number for readability (as the hyphen in the above example). After you hit return, the computer picks up the phone, waits a second and starts to dial your number (the cursor will flash to indicate the dialing). When the dialing is complete, the computer will print: DIALING COMPLETE Getting back to the menu: To get back to the menu, type: & Note that when you return to The Terminal anything you may have had on the display will be lost. Messages printed by The terminal: When you are using the D.C. Hayes card, the computer will indicate when the carrier is present and when it is lost by printing the messages: {CARRIER PRESENT} or {CARRIER LOST} Characters to be sent to the display are temporarily stored in an input buffer in the memory of the Apple. Likewise, characters to be sent to the modem are stored in an output buffer. When The Terminal is doing especially time consuming work (e.g., scrolling or visual bell), characters build up in these two buffers. Over extended periods of time consum- ing work, it is possible that these buffers can overflow. When this happens, the messages: {INPUT BUFFER OVERFLOW} and/or {OUTPUT BUFFER OVERFLOW} will be printed as is appropriate. The Menu Parameters and Values: Parameter Values Description --------------------------------------------------------------------- Communications Apple, Chooses the appropriate card. card D.C. Hayes Baud Rate 75,110,300,440 Sets the speed of the communications card (the D.C. Hayes card only oper- ates at 110 or 300 baud). Transmission 7 or 8 data bits Sets the communications format used Protocol 1 or 2 stop bits by the communications card. even, odd, or no parity Slot 1 through 7 Sets the interface slot to the location of the communications card. Duplex full/half Full- The Terminal expects characters to be echoed by the remote com- munications device. Half- The Terminal echoes characters typed by the user to the dis- play. Echo on/off When on, characters sent to The Ter- minal by the remote device are echoed back to the remote device. Key Click on/off When on, the speaker "clicks" each time a character is sent. Background black/white The display can be used with a black background with white letters, or a white background with black letters. Auto Line Feed on/off When on, each carriage return will also cause the cursor to move to the next line as well as the beginning of the line (otherwise, an explicit line feed must be received). Wrap around on/off When on, lines extending past the right margin are continued on the next line (otherwise, characters printed beyond the right margin over- print in the last column). Bell audio/visual Audio- The Terminal gives an audio indication when receiving a bell. Visual-The Terminal gives a visual indication when receiving a bell. Display Control Characters: The following table outlines the display control characters recognized by The Terminal. Character Sequence Action --------------------------------------------------------------------- A Moves the cursor up one line (not beyond the top of the display). B Moves the cursor down one line (not beyond the bottom of the display). C Moves the cursor right one column (if wrap around is on, then attempting to move beyond the right margin moves the cursor to the beginning of the next line). D Moves the cursor left one column (if wrap around is on, then attempting to move beyond the left margin moves the cursor to the end of the previous line). H Moves the cursor to the home position (top left of the display). I Moves the cursor up one line (a scroll down is performed if the cursor is at the top margin). J Erase all characters from the cursor to the end of the display. K Erase all characters from the cursor to the end of the line. Y line col Move the cursor to the specified line and column (line, and column numbers are the ASCII code received minus $20, e.g., to position the cursor at the home position, line-0, column-0, Y $20 $20 would be sent). Z Identifier request. The Terminal responds: K L Insert line (every line from the current one to the bottom of the display is scrolled down ). M Delete line (the current line is deleted and all the lines beneath it are scrolled up). Q $20 $08 R Insert character (every character in the cur- rent line beneath or to the right of the cursor is moved to the right one column- some characters may be pushed off the end of the line). P Delete character (deletes the character be- neath the cursor and shifts all characters to the right of the cursor, one column to the left). --------------------------------------------------------------------- For further information, contact: Michael C. Koss 1502 Westgate Cambridge, MA 02139 (617)-494-1097