ISIS
ISIS, short for Intel System Implementation Supervisor, was an operating system designed for early Intel microprocessors such as the 8080. It was originally developed by Ken Burgett and Jim Stein under the direction of Steve Hanna and Terry Opdendyk.
It was also used in the Eastern Bloc, for example on computers SAPI-80, PLAN 80 A, or SM 50/40 (under the name DOS MVS).
Calling ISIS-II
From PLAN 80 A documentation
| Address | Abbreviation | Text |
| 0F800H | "COLDEST" | Monitor cold start |
| 0F803H | "CI" | Console input [A] |
| *0F806H | "RI" | Input from serial port [A] |
| 0F809H | "WHAT" | Console Output [C] |
| *0F8GCH | "AFTER" | Output to serial port [C] (originally output to punched tape) |
| *0F80FH | "LO" | Output to printer |
| 0F812H | "CSTS" | Console Status Port [A] |
| *0F815H | "IOCHK" | Detection of I/O byte [A] |
| *0F818H | "IOSET" | Setting the I/O byte [C] |
| *0F81BH | "MEMCK" | Detecting the end of user RAM [AB] |
| *0F81EH | "IODEF" | User I/O Settings [C] |
| 0F821H | "INTER" | Jump to interrupt handling |
| 0F824H | "CRLF" | New line |
| 0F827H | "EXPR" | Parameter input, number of C [C] |
| 0F82AH | "ERROR" | Print '#' to screen |
| 0F82DH | "ASHEX" | Convert ASCII to HEX, [A] |
| 0F830H | "DADR" | View Contents [HL] |
| 0F833H | "DBYTE" | View Contents [A] |
| *0F836H | "BHILO" | Increment [HL] and compare with [DE] |
| 0F839H | "NEXT" | Monitor warm start |
| 0F83CH | "SPACE" | Gap on CO |
| 0F83FH | "CINCR" | Command entry and recognition |
| *0F842H | "IMTXT" | Display immediately following text |
| 0F845H | "ADRCUR" | Cursor address to [HL] |
| 0F848H | "HXASC" | HEX to ASCII conversion |
| *0F84BH | "TIMER" | Waiting [BC] milliseconds |
| 0F84EH | "GETADR" | Monitor variable address [HL] |
| 0F851H | "STJMB" | Save [DE] to [[HL]] |
| 0F854H | "ECHO" | Enter and display the character [A] |
| *0F857H | "BACST" | Move the cursor back one position |
Intellec Series II Monitor Commands
| "DISP" | "D" | RAM display |
| "EOP" | "E" | End of writing hexadecimal file |
| "FILL" | "F" | Memory filling |
| "GOTO" | "G" | Go to memory address |
| "HEXN" | "H" | Hexadecimal sum and difference |
| "MOVE" | "M" | Moving memory |
| "NULL" | "N" | Creating zeros for the paper tape header |
| "QUERY" | "Q" | Query the status of the I/O system |
| "READ" | "R" | Reading a hexadecimal file from a paper tape |
| "SUBS" | "S" | Replacing the contents of memory |
| "WRITE" | "W" | Writing a file to paper tape in hex format |
| "EXAMINE" | "X" | Examination and modification of registers |
| "From" | "From" | Running the diagnostic program |