Zero page constants/variables used in APL: Constants --------- 104 01FE Current instruction fetch routine (may be 01FE or 020A) 1E6 01FE Normal instruction fetch routine (from ROS) 1E8 020A Alternate instruction fetch routine (from RWS) 1C4 0000 1C6 0000 136 04A4 Set Condition Code 0 and continue 138 04A8 Set Condition Code 1 and continue 13A 04AC Set Condition Code 2 and continue 13C 04B0 Set Condition Code 3 and continue 13E 04B4 Fixed-point overflow 134 0100 General processor registers (see below) 124 0108 Floating-point registers (see below) 126 0188 Same as 124, but with bit 8 set 17C 021A Fetch operands; format R1,D2(X2,B2) [RX] 1AC 021A ROS fetch 1A4 0272 RWS fetch 17E 0224 Fetch operands; format FR1,D2(X2,B2) [RX] 1AE 0224 ROS fetch 1A6 0282 RWS fetch 184 022E 186 0292 Fetch operands; format D2(B2) [RS] 1B4 0292 ROS fetch 1A8 02B2 RWS fetch 188 02C2 Fetch operands; format D1(B1) [SI] 1DA 02C2 ROS fetch 1D4 02EC RWS fetch 18A 02FA Fetch operands; format D1(L,B1),D2(B2) (RWS/ROS) [SS] 1DC 02FA ROS fetch 1D6 036E RWS fetch 18C 0328 Fetch operands; format D1(L,B1),D2(B2) (RWS only) [SS] 1DE 0328 ROS fetch 1D8 0388 RWS fetch 18E 03A4 1B6 03A4 ROS 1AA 03B0 RWS Fetch data from 24 bit address space (i.e. from ROS) ---------------------------------------------------- 158 04CC Fetch 8 bytes 15A 04D0 Fetch 1 byte from next even address 15C 04DE Fetch 2 bytes 15E 04E2 Fetch 4 bytes 156 0542 Fetch 1 byte (special routine) 164 2970 166 2A2C 174 2AE8 Normalize floating point number in R3/R4/R5/R6 176 2C12 Normalize floating point number in R7/R8/R9/R10 154 0A00 Work area e.g. for multiplication 1EA 2D60 Switch operand fetch routines to ROS 1EC 2D3C Switch operand fetch routines to RWS 106 0800 Start of vector table in RWS 1CE 0172 Restart address of /360 emulator Variables --------- 144 Temporary storage 146 CPU Program Mask Bits (lower nibble) 194 Temporary storage; used as Old PSW in except. routine 196 Temporary storage 19C Temporary storage 1EE Instruction Pointer when executing from RWS 1E4 0: Execution from ROS 0100-103 R0 - General register 0 (32 bits) 0110-113 R1 0120-123 R2 0130-133 R3 ... ... 01E0-1E3 R14 01F0-1F3 R15 - General register 15 (32 bits) 0108 FR0 - Floating-point register 0 (64 bits) 0118 FR2 - Floating-point register 2 (64 bits) 0128 FR4 - Floating-point register 4 (64 bits) 0138 FR6 - Floating-point register 6 (64 bits) 0119-11C Temporary storage for multiplier RWS locations used ------------------ 0800-09FF Instruction vector table