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Table of Opcodes
| 2OPs | ZIP | EZIP/LZIP | XZIP | YZIP | Returns | Summary |
|---|---|---|---|---|---|---|
| 000 | - | - | - | - | ||
| 001 | EQUAL? any1,any2 | PRED | Is any1 equal to any2? | |||
| 002 | LESS? int1,int2 | PRED | Is int1 less than int2? | |||
| 003 | GRTR? int1,int2 | PRED | Is int1 greater than int2? | |||
| 004 | IGRTR? var,int | PRED | Increments the value of var by one and succeeds if the new value is greater than int. | |||
| 005 | DLESS? var,int | PRED | Decrements the value of var by one and succeeds if the new value is less than int. | |||
| 006 | IN? obj1,obj2 | PRED | Is obj1 contained in obj2? | |||
| 007 | BTST word1,word2 | PRED | Is every bit that is on in word2 also on in word1? | |||
| 008 | BOR word1,word2 | VAL | Bitwise logical or. | |||
| 009 | BAND word1,word2 | VAL | Bitwise logical and. | |||
| 010 | FSET? obj,flag | PRED | Is this flag number set in obj? | |||
| 011 | FCLEAR obj,flag | Clear flag in obj. | ||||
| 012 | - | - | - | - | ||
| 013 | SET var,any | Sets the specified variable to any. | ||||
| 014 | MOVE obj1,obj2 | Put obj1 into obj2. | ||||
| 015 | GET table,item | VAL | Interpreting the table pointed to as a vector of words, returns the item'th element. In other words, returns the word pointed to by item times two plus table. (Tables begin with element zero.) | |||
| 016 | GETB table,item | VAL | Similar to GET, but assumes a byte table. Returns the byte (converted to a word, of course) pointed to by item plus table. | |||
| 017 | GETP obj,prop | VAL | Returns specified property of obj. If obj has no property prop, returns prop'th element of default property table. | |||
| 018 | GETPT obj,prop | VAL | Gets property table prop from obj. Where GETP can only be used with single byte or single word properties, GETPT can be used with properties of any length. It returns a pointer to the property value that may then be used as a table pointer in any other table operation. | |||
| 019 | NEXTP obj,prop | VAL | Returns the number of the property following prop in obj. Error if no property prop exists in obj. Returns zero if prop is last property. Given proper equal to zero, returns first property (i.e. is circular). | |||
| 020 | ADD int1,int2 | VAL | Adds the integers. | |||
| 021 | SUB int1,int2 | VAL | Subtracts int2 from int1. | |||
| 022 | MUL int1,int2 | VAL | Multiplies the integers. | |||
| 023 | DIV int1,int2 | VAL | Divides int1 by int2, returning the truncated quotient. | |||
| 024 | MOD int1,int2 | VAL | Divides int1 by int2, returning the remainder. | |||
| 025 | - | - | - | - | ||
| 026 | - | - | - | - | ||
| 027 | - | - | - | - | ||
| 028 | - | - | - | - | ||
| 029 | - | - | - | - | ||
| 030 | - | - | - | - | ||
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| 032 | - | - | - | - | ||
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| 099 | - | - | - | - | ||
| 100 | - | - | - | - | ||
| 101 | - | - | - | - | ||
| 102 | - | - | - | - | ||
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| 120 | - | - | - | - | ||
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| 122 | - | - | - | - | ||
| 123 | - | - | - | - | ||
| 124 | - | - | - | - | ||
| 125 | - | - | - | - | ||
| 126 | - | - | - | - | ||
| 127 | - | - | - | - | ||
| 1OPs | ZIP | EZIP/LZIP | XZIP | YZIP | Returns | Summary |
| 128 | ZERO? any | PRED | Is any equal to zero? | |||
| 129 | NEXT? obj | VAL/PRED | Returns “next” slot of obj. Fails if none (equals zero) and returns zero. | |||
| 130 | FIRST? obj | VAL/PRED | Returns “first” slot of obj. Fails if non (equals zero) and returns zero. | |||
| 131 | LOC obj | VAL | Return container of obj, zero if none. | |||
| 132 | PTSIZE table | VAL | Given a property table pointer as may be obtained from GETPT, returns the length of this “table” in bytes. Guaranteed to return a meaningless value if given any other kind of table. (Assumes that the byte preceding the table is a property identifier.) | |||
| 133 | INC var | Increments the value of var by one. | ||||
| 134 | DEC var | Decrements the value of var by one. | ||||
| 135 | PRINTB str | Like PRINT, but str here is an ordinary byte pointer. | ||||
| 136 | - | - | - | - | ||
| 137 | REMOVE obj | MOVEs obj to pseudo-object zero. | ||||
| 138 | PRINTD obj | Prints the short description of obj. | ||||
| 139 | RETURN any | Causes the most recently executed CALL to return any and continues execution at the next sequential instruction after that call. | ||||
| 140 | JUMP loc | An unconditional branch to the location of the next sequential instruction plus loc minus two (for compatibility with predicates). Not that unlike the predicate argument, this is a full twos-complement word. | ||||
| 141 | PRINT str | Prints the string pointed to by str times two. The multiplication is necessary because str in this instruction is a word-pointer, guaranteed to point to a string that has been word-aligned. | ||||
| 142 | VALUE var | VAL | Returns value of var. | |||
| 143 | BCOM word | VAL | Bitwise logical complement. | |||
| 144 | - | - | - | - | ||
| 145 | - | - | - | - | ||
| 146 | - | - | - | - | ||
| 147 | - | - | - | - | ||
| 148 | - | - | - | - | ||
| 149 | - | - | - | - | ||
| 150 | - | - | - | - | ||
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| 152 | - | - | - | - | ||
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| 154 | - | - | - | - | ||
| 155 | - | - | - | - | ||
| 156 | - | - | - | - | ||
| 157 | - | - | - | - | ||
| 158 | - | - | - | - | ||
| 159 | - | - | - | - | ||
| 160 | - | - | - | - | ||
| 161 | - | - | - | - | ||
| 162 | - | - | - | - | ||
| 163 | - | - | - | - | ||
| 164 | - | - | - | - | ||
| 165 | - | - | - | - | ||
| 166 | - | - | - | - | ||
| 167 | - | - | - | - | ||
| 168 | - | - | - | - | ||
| 169 | - | - | - | - | ||
| 170 | - | - | - | - | ||
| 171 | - | - | - | - | ||
| 172 | - | - | - | - | ||
| 173 | - | - | - | - | ||
| 174 | - | - | - | - | ||
| 175 | - | - | - | - | ||
| 0OPs | ZIP | EZIP/LZIP | XZIP | YZIP | Returns | Summary |
| 176 | RTRUE | Does a “RETURN 1,” where 1 is commonly interpreted by Z programs as “true.” | ||||
| 177 | RFALSE | Does a “RETURN 0,” where 0 is commonly interpreted by Z programs as “false.” | ||||
| 178 | PRINTI (str) | Prints an immediate string. Interpreted as a 0-operation instruction but immediately followed by a standard string (as opposed to a string-pointer). | ||||
| 179 | PRINTR (str) | Like PRINTI byut executes a CRLF followed by an RTRUE after printing the string. | ||||
| 180 | NOOP | No operation, equivalent to a “JUMP 2.” | ||||
| 181 | SAVE | PRED | Writes the “impure” part of the game to disk in some recoverable format. The seed for RANDOM should not be saved or restored so that multiple RESTOREs from the same SAVEd game will not necessarily lead to the same results. Other details of the user interface are left to the discretion of the implementor. Not that this instruction is a predicate. | |||
| 182 | RESTORE | PRED | Recovers a previously SAVEd game and continues execution aft erthe SAVE. If the RESTORE fails, execution should continue (if possible) after the RESTORE in the original game with the instruction failing. | |||
| 183 | RESTART | Reinitializes the game and generally acts as if it had just been restarted. | ||||
| 184 | RSTACK | Does a “RETURN STACK,” thereby returning from a CALL and taking the value from the (old) top of the stack. | ||||
| 185 | FSTACK | Flushes the top off the stack. | ||||
| 186 | QUIT | The game should die peacefully. | ||||
| 187 | CRLF | Prints an end-of-line sequence (carriage-return/line-feed in ASCII). | ||||
| 188 | USL | Updates the status line now instead of waiting for the next READ. | ||||
| 189 | VERIFY | PRED | Verifies the correctness of the game program stored on disk by comparing the 16-bit sim of the bytes in the program, from byte 64 to byte PLENGTH*2-1, with PCHKSUM. Not that for the preloaded area, the unmodified pages on the disk should be used rather than the pages in core. | |||
| 190 | - | - | - | - | ||
| 191 | - | - | - | - | ||
| XOPs | ZIP | EZIP/LZIP | XZIP | YZIP | Returns | Summary |
| 192 | - | - | - | - | ||
| 193 | EQUAL? any1,any2[,any3][,any4] | PRED | Is any1 equal to any2, any3, or any4? | |||
| 194 | - | - | - | - | ||
| 195 | - | - | - | - | ||
| 196 | - | - | - | - | ||
| 197 | - | - | - | - | ||
| 198 | - | - | - | - | ||
| 199 | - | - | - | - | ||
| 200 | - | - | - | - | ||
| 201 | - | - | - | - | ||
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| 205 | - | - | - | - | ||
| 206 | - | - | - | - | ||
| 207 | - | - | - | - | ||
| 208 | - | - | - | - | ||
| 209 | - | - | - | - | ||
| 210 | - | - | - | - | ||
| 211 | - | - | - | - | ||
| 212 | - | - | - | - | ||
| 213 | - | - | - | - | ||
| 214 | - | - | - | - | ||
| 215 | - | - | - | - | ||
| 216 | - | - | - | - | ||
| 217 | - | - | - | - | ||
| 218 | - | - | - | - | ||
| 219 | - | - | - | - | ||
| 220 | - | - | - | - | ||
| 221 | - | - | - | - | ||
| 222 | - | - | - | - | ||
| 223 | - | - | - | - | ||
| 224 | - | - | - | - | ||
| 225 | PUT table,item,any | Inverse of GET. Sets the word pointed to to any. | ||||
| 226 | PUTB table,item,any | PUTB is to GETB as PUT is to GET. Uses only the lower order byte of any. Error if the high-order byte is non-zero. | ||||
| 227 | PUTP obj,prop,any | Changes value of obj's property prop to any. Error if obj does not have that property. | ||||
| 228 | READ table1,table2 | Reads and parses a line of input. Rable1 is the buffer used to store the characters read. The first byte (read-only) contains the length of the rest of the buffer where the input string is stored. Table2 stores the results of the parse. The first byte (read-only) of this table specifies the maximum number of words (of text, not machine words) that may be stored here. | ||||
| 229 | PRINTC int | Prints the character whose ASCII value is int. | ||||
| 230 | PRINTN int | Print int as a signed number. | ||||
| 231 | RANDOM int | VAL | Returns a random value between 1 and int, inclusive. | |||
| 232 | PUSH any | Pushes any onto the stack. | ||||
| 233 | POP var | Pops the top word off the stack and puts it into var. Note that “POP 'STACK” will have the effect of flushing the next to the top word of the stack. | ||||
| 234 | SPLIT int | If option bit 5 in the mode byte is zero, this operation is ignored otherwise it divides the screen into two windows: #1 occupies int lines, preferably at the top of the screen, and #0 occupies the remainder of the screen. If int is zero, this operation restores the normal screen format. Window #1 is special in that it never scrolls if the program outputs characters beyond the right-hand margin, they are not displayed. | ||||
| 235 | SCREEN int | If option bit 5 in the mode byte is zero, this operation is ignored otherwise it causes subsequent screen output to fall into window #int. If int is 1, the output cursor is moved to the upper left-hand corner. If int is 0, the output cursor is restored to its previous position. This operation is ignored if the screen is not split, or if int is not zero or one. | ||||
| 236 | - | - | - | - | ||
| 237 | - | - | - | - | ||
| 238 | - | - | - | - | ||
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| 251 | - | - | - | - | ||
| 252 | - | - | - | - | ||
| 253 | - | - | - | - | ||
| 254 | - | - | - | - | ||
| 255 | - | - | - | - | ||
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