Revision as of 02:10, 12 June 2011 view source rosettacode>Markhobley {{header\|ZX Spectrum Basic}} ← Older edit		Revision as of 09:34, 12 June 2011 view source rosettacode>Markhobley {{header\|ZX Spectrum Basic}} Newer edit →
Line 350: === {{header\|ZX Spectrum Basic}} === The ZX Spectrum uses single letter variables names. None of these are special variables. There are a set of system variables held at a fixed memory addresses, which can be accessed via PEEK and POKE functions. The system variables and addresses are: 23552 KSTATE - Keyboard state. 23560 LAST K - Newly pressed key. 23561 REPDEL - Delay (in 50ths of a second) before keyboard starts repeating. 23562 REPPER - Delay (in 50ths of a second) between keyboard repetions. 23563 DEFADD - Address of arguments for a user defined function. 23565 K DATA - Second byte of colour controls sequences from keyboard. 23566 TVDATA - Colour and location information for television set. 23568 STRMS - Addresses of channels attached to streams. 23606 CHARS - 256 less than the address of the current character set 23608 RASP - Length of the warning buzz. 23609 PIP - Length of the keyboard click. 23610 ERR NR One less than the error code and starts at 255 (for -1) 23611 FLAGS - Various flags to control the BASIC system. 23612 TV FLAG - Flags associated with the television output. 23613 ERR SP - Address of item on machine stack to be used as error return. 23615 LIST SP - Return address from automatic listing. 23617 MODE - Cursor type 23618 NEWPPC - Line number to be jumped to. 23620 NSPPC - Statement number in line to be jumped to 23621 PPC - Line number of statement currently being executed. 23623 SUBPPC - Statement number within the line that is currently being executed. 23624 BORDCR - Colour of the border (overscan area) and input area (times 8) 23625 E PPC - Current line number (for list editing) 23627 VARS - Address of the variables. 23629 DEST - Address of variable in assignment. 23631 CHANS - Address of channel data. 23633 CURCHL - Address of information being used for input and output. 23635 PROG - Address of the BASIC program. 23637 NXTLIN - Address of the next line in the program. 23639 DATADD - Address of terminator of the last DATA item. 23641 E LINE - Address of command being typed in. 23643 K CUR - Address of the cursor. 23645 CH ADD - Address of the next character to be interpreted 23647 X PTR - Address of the character after the syntax error marker. 23649 WORKSP - Address of temporary work space. 23651 STKBOT - Address of bottom of calculator stack. 23653 STKEND - Address of start of free space. 23655 BREG - The B register of the calculator. 23656 MEM - Address of area used for calculator memory. 23658 FLAGS2 - Miscellaneous flags. 23659 DF SZ - The number of lines in the input area. 23660 S TOP - The number of the top program line in automatic listings. 23662 OLDPPC - Line number to which CONTINUE jumps. 23664 OSPPC - Number within line of statement to which CONTINUE jumps. 23665 FLAGX - Various flags. 23666 STRLEN - Length of string type destination in assignment. 23668 T ADDR - Address of next item in the syntax table. 23670 SEED - The random number seed. 23672 FRAMES - A 3 byte frame counter incremented every 20ms. 23675 UDG - Address of the user defined graphics 23677 COORDS Coordinates of the last point plotted. 23679 P POSN - Column number for the position of the printer carriage. 23680 PR CC - Address of next free position in the printer buffer. 23682 ECHO E - Column and line number positions in the input buffer. 23684 DF CC - Display address for the current print position. 23686 DFCCL - Display address in the input area. 23688 S POSN - Column and row number of the print position. 23690 SPOSNL - Column and row number for the print position in the input area. 23692 SCR CT - Scroll counter - Number of lines left before stopping with Scroll? 23693 ATTR P - Permanent current colours attributes 23694 MASK P - Permanent current colour attribute mask 23695 ATTR T - Temporary current colour attributes 23696 MASK T - Temporary current colour attribute mask 23697 P FLAG - More flags. 23698 MEMBOT - Memory area address used by the calculator 23728 NMIADD - The address of the users Non Maskable Interrupt service routine. 23730 RAMTOP - Address of last byte of BASIC system area. 23732 P-RAMT - Address of last byte of physical RAM. <lang zxbasic>10 PRINT "The border colour is "; PEEK (23624): REM bordcr

Special variables: Difference between revisions