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ROPE - "Hello World"

The goal of this page is
    - write, assemble, run your 1st sample 1401 program on your PC
    - "try this thing out"
    - "YES, I can do this !!" :-))
I hope this description is a "ROPE For Dummies" ;-))

Introduction
One reason the IBM 1401 was so popular was that it was so simple to setup (program) and use
    (Inspite of its famous sales force and service, IBM had some flops.)

The IBM 1401 was designed to be a simple "swing machine" between
   the plug boards of the "Unit Record" card equipment,
    such as the 083 sorter, the 077 collator (merger), and the 402 "accounting machine",
and
    the coming stored program (no plug boards) computers
    such as we all use today.
It is a very simple machine to learn and use character decimal machine,
    such as the ADD instruction in memory is the character A
    and addresses are character numbers, such as 123
no need to learn binary :-))

Here is a hint of the simplicity.
Looking complicated, this is the General Electric 225 operator's panel, designed (in part) to compete with the IBM 1401. A data word was 20 binary bits, data range +- 524288. The IBM 1401 operator's panel, looking less complicated, also giving useful data paths. Data was in decimals characters, ending in a word mark, data range greater than +- 999,999,999,999,999,999,999,...

OK !! Lets Start,
Step 1
Assuming you have looked at Introduction to ROPE
    - which shows how to down load ROPE
    - introduces you to various screens and concepts
let us think of a simple program.

Let us "print out" the famous "HELLO WORLD" :-))
    This simple operation gives confidence that you are flying !!! ;-))

We assume you have:
    - down loaded ROPE as described here
    - started ROPE and looking at the Edit Screen
    - loaded existing source code ( .s ), assembled it, looked at the listing,
    - - - amd run the code, viewing the printed output, looked at memory and status
So - now what ??? ;-))


Step 2 Make a source file called "HelloWorld.s"
You cannot originate a .s file in ROPE, so, use Windows NotePad
- type in a simple program and run this simple program :-))
    - you should read the manua


Step 3 Use ROPE to load and edit this new "HelloWorld.s" file
You cannot originate a .s file in ROPE, so, use Windows NotePad
- type in a simple program and run this simple program :-))
    - you should read the manua



  1. activate "Windows Explorer" (this is not "Internet Explorer") by
    1. in the lower left of the screen, click on "Start"
    2. in the new window, click on "Computer"
    3. This brings up a little window called "Computer" which shows your disks
    4. DoubleClick on your " C: " drive which shows the directories (folders) it contains

  2. Go to your " ROPE " directory/folder
    - you are looking at a " Windows Explorer " window with about 18 oddly names files
    - the file you want to start is " ROPE1401.jar "

  3. Double click on " ROPE1401.jar ", and if you have JAVA installed and able to activate,
    - you get the opening " ROPE " window
    - labeled " ROPE/1401 by Ronald Mak (Version 0.7 Beta) " :-))

This is a series of displays

Directory screen 		. This is the " Windows Explorer " (detail mode) of most of the ROPE directory from the .zip file.
The " ROPE1401.jar " entry is highlighted.
DoubleClick on this to get started (below)

Edit screen
Detail 		This is the initial ( Edit ) display
You have choices of:
- " Browse " for existing files
- edit file in window
- name a new file, rename and/or save existing file
- change Assembler options (current default are OK)
- cause file to be assembled ( AutoCoder )

Browse screen 		. This is the " ROPE " Browse window, the " .s " files indicate source files
lets select " powers2.s "
You will DoubleClick on this to get started (below)

powers2 source
powers2 detail 		OK - this is the powers2.s file, ready for editing, saving as, or assembling :-))

Remember that you need an END-AND-TRANSFER card, the last card in this deck is
" END PRINTD * LAST CARD IN DECK, TRANSFER ADDRESS "


Assembled window
"Listing" detail 		Depressing the " Assemble " button on the Edit window yields two more windows
- EXEC:powers2 - shows the " assembly listing ", often printed during assembly
- PRINTOUT:powers2 - still blank as the assembled program not yet run

"Listing" detail 		. Note some of the controls in this window
- " Start Program " - starts program which runs until breakpoint or end
- " Mempry " shows the selected range of memory

PRINTOUT top
PRINTOUT bottom 		The running power2 prints out onto the printer
- " PRINTOUT top " - the beginning of the printout, goes several pages
- " PRINTOUT bottom " shows the end (bottom) of the "1403" printout

Computer memory 		. This is contents of the user option range of 1401 memory.
It is in printer memory dump format, the " 1 "s below the contents
indicate the position of the word marks.

Console indicators 		. Console indicators and switches :-))

BreakPoint indicators 		When program execution
reaches a breakpoint,
it is suspended.
You may examine memory
and console. 		Program "development", sometimes called "debugging" ;-))

BreakPoint indicators - you can debug programs in several ways
- Run to setable breakpoints
- - clicking on the blue cross sets red breakpoints - toggle
- Single step - the memory and console and printouts show correctly

See more detailed instructions for attaching peripherals such as
card reader, card punch, magnetic tapes.

ROPE file naming conventions
xxx.cd - card punch (object deck) output from AutoCoder assembler (in ASCII rather holes in card)
You may actually punch out this deck this method which loads and runs on a 1401.
xxx.out - printer output from user program (in ASCII)
xxx.s - source program code to AutoCoder assembler (in ASCII rather than BCD)
xxx.lst - printed "listing" from AutoCoder assembler (in ASCII)

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Started Jan 20, 2012
Last updated Jan 22, 2012
For comments, corrections, questions e-mail Ed Thelen ed@ed-thelen.org