Club 100 Library - 415/939-1246 BBS,    937-5039 NEWSLETTER, 932-8856 VOICE

INSIDE.BA PROGRAM DOCUMENTATION

by: Bill Templeton
    10-15-86


        The program, INSIDE.BA, is particularly useful when you are reading Carl Oppedahl's book, `Inside the Model 100,' as it uses hexidecimal references to important ROM and RAM addresses on almost every page!

        Even if you never plan to POKE a number-pair discussed below into your M100's RAM, you might want to run this program to learn more about why hexidecimal numbers are used in the design of a computer's memory.

        Try converting this series of HEX VALUES and look carefully at their decimal equivalents to gain further insights into your M100/102/200: 0001, 0010, 0100, 1000, 2000, 4000, 6000 and 8000.

        Or conversly, convert this series of DECIMAL numbers and note their decimal equivalents: 1, 16, 256, 4096, 8192, 16384, 24576 and 32768.

        You might have somthing more specific in mind, like how to quickly decipher Carl's memory map on p.81 of his book, or how to make more sense out of his discussion of PEEKs and POKEs on pgs. 60-62!  In any case, INSIDE.100 will save you lots of valuable time!

        As an example, lets say you're trying to figure out how to poke a 4-digit hexidecimal number (FACE) into RAM address X.  Remember, the discussion below about low-order/high-order numbers applies only when you are poking a number greater than 255 (FFh) and less than 65536 (10000h) into your M100's memory!

        Without a calculator, it would take days to perform these calculations!  Even with a normal calculator, without hex-to-decimal conversions, it would take many hours.  And with a Radio Shack or TI programmers calculator, with hex conversions, it takes several minutes.

        But with INSIDE.BA, it takes a couple of seconds, and less than a minute to perform several calculations in succession!

        You first need to convert the hex value (FACE) to its decimal equivalent, so you would press <2> in INSIDE.100's menu, enter the hex value (with CAPS LOCK key down), and before you can say `Jack Robinson,' you have the decimal equivalent (64206).

        Then, press <ESC> to return to the programs menu, and press <1> to convert this decimal equivalent to the two parts (low-order/high-order) you need to POKE the value 64206 into RAM.

        The program quickly shows you that you must POKE X,206 and POKE X+1,250 to put the hex value, FACE, into your M100's memory in such a way that it can use it to, say, jump to that address in the event it is told to do so.  And it only takes a few seconds to get these numbers once you become familiar with the program.

        One thing that should be clarified regarding INSIDE.BA:  If you press <ENTER> when in the program's main menu, or at the end of a conversion, you will convieniently return to the M100's main menu.  And, after selecting <1> or <2> in the program's main menu, if you press <ENTER> or <ESC> respectively in these two subroutines, you will return to the PROGRAM's main menu.

Enjoy!  Bill