Club 100 Library - 415/939-1246 BBS, 937-5039 NEWSLETTER, 932-8856 VOICE INSIDE.100 MEMORY MAP by: Bill Templeton 10-15-86 As many of us have learned by now, the M100's Microsoft BASIC will not perform operations on integers larger than 32767, so in these cases, you must use the negative compliment by subtracting 65536 from such an integer. Here is a memory map showing some of the more important M100 memory addresses, put together with the help of the INSIDE.100 program: Decimal Hexidecimal Area -------------- ------------- ------ 0 -65536 0 -10000 ROM 16 -65520 10 -FFF0 " 256 -65280 100 _FF00 " 4096 -61440 1000 -F000 " 8192 -57344 2000 -E000 " 16384 -49152 4000 -C000 " 24576 -40960 6000 -A000 " -------------- ------------- ------ 32768 -32768 8000 -8000 RAM#4 40960 -24576 A000 -6000 RAM#3 49152 -16384 C000 -4000 RAM#2 57344 -8192 E000 -2000 RAM#1 61440 -4096 F000 -1000 -------------- ------------- ------ 62960 -2576 F5F0 -A10 MAXRAM 65280 -256 FF00 -100 65520 -16 FFF0 -10 65535 -1 FFFF -1 So you can see again that the M100's ROM takes up half of the total gross memory, or 32768 bytes (from 0 to 32767)! And the M100's system RAM takes 2576 bytes of overhead, from 62960 to 65535, which are reserved for M100 operation. As explained in another bulletin, another 554 bytes of RAM is taken for miscellaneous overhead (MAXFILES, string variables, etc.). So a total of 3130 bytes must be substracted from the GROSS memory of your M100 to give you the NET memory available for your use! Net Bytes M100 Memory Free ---- ---------- ----- 8K 8192-3130 = 5062 24K 24576-3130 = 21146 32K 32768-3130 = 29638 And don't forget, if you use a portable 3.5" Chipmunk disk drive, the Disk Operating System (CDOS) takes up another 4993 bytes, so the NET memory available decreases to 24645 bytes on a 32K M100. And when formatting a Chipmunk disk, you need at least 6791 bytes free in the main menu (or 6535 in BASIC), so instead of having 32K of usable memory, it's more like 23K when all things are considered (29638 - 6791 = 22847 bytes). However, the Chipmunk's STORAGE CAPACITY (360K/disk) and SPEED (fast parallel buss!) and ability to store FILES within FOLDERS (like UNIX) and `SAVE ALL'/`LOAD ALL' commands and AUTO-DIRECTORY feature, more than make up for the memory lost to overhead! Best of luck... Bill