Uploaded unfinished libraries.

Programs/Libraries/int8.asm

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+; This file supplies basic support for int8 values.
+
+#Program
+
+; Basic int8 subroutines.
+
+; An int8 value is an 8 bit unsigned integer. Just a byte literally interpreted as a value.
+; Basic operations on int8 values use A and B as operands with the result returned in Q, similar to the bare arithmetic instructions of SplitBit.
+
+int8mult:
+  ; Multiply A by B and return the result in Q.
+  ; This subroutine is limited to outputs in the range of 0-255.
+  ; It does not reliably return with the Carry Flag set if the result is too large to fit in the range.
+  ; First, check if either is zero, and if so, return zero.
+  BRB return0
+  BRA return0
+  PSHB ; Push the multiplier to the stack.
+  PSHA ; Push the multiplicand to the stack.
+  POPB ; Pop the multiplicand into B.
+  RSTA ; Set A to 0.
+  CCF  ; Clear the Carry Flag, just in case.
+ int8multLoop:
+  ADD  ; Add the multiplicand to A.
+  POPA ; Pop the multiplier into A.
+  DECA ; Subtract one from the multiplier.
+  BRA int8multDone ; If the multiplier becomes zero, we're done.
+  PSHA ; Push the multiplier back to the stack.
+  PSHQ ; Push the running total to the stack.
+  POPA ; Pop the running total into A.
+  BRI int8multLoop
+ return0:
+  RSTA
+  RSTB
+  ADD
+ int8multDone:
+  RET
+
+int8div:
+  ; Divide A by B and return the quotient in Q.
+  ; First, check if either A or B are 0, if so, return 0.
+  BRB return0
+  BRA return0
+  ; This dance of pushes, pops, and addition creates a quotient counter on the Stack while preserving A and B.
+  PSHA ; Push A to the Stack.
+  PSHB ; Push B to the Stack.
+  RSTA ; Set A and B to 0.
+  RSTB
+  ADD  ; Add them together, setting Q to 0.
+  POPB ; Restore B.
+  POPA ; Restore A.
+  PSHQ ; Push a 0 onto the Stack.
+  ; The Carry Flag is clear and we can proceed with the division.
+ int8divLoop:
+  SUB  ; Subtract B from A.
+  ; If we generate a carry we're done.
+  BRC int8divDone
+  ; Otherwise, increment the quotient counter and subtract again.
+  POPA ; Pop the quotient counter from the stack.
+  INCA ; Increment it.
+  PSHA ; Push it back onto the stack.
+  PSHQ ; Push the running total onto the stack.
+  POPA ; Pop the runing total into A.
+  BRI int8divLoop ; Branch back to the loop.
+ int8divDone:
+  CCF  ; Clear the Carry Flag.
+  POPA ; Pop the quotient into A.
+  RSTB ; Set B to 0.
+  ADD  ; Add them together to move the result to Q.
+  RET  ; Return to the caller.
+
+int8mod:
+  ; Divide A by B and return the remainder in Q.
+  ; If A or B are 0, return 0.
+  BRB return0
+  BRA return0
+ int8modLoop:
+  SUB ; Subtract B from A.
+  BRC int8modDone
+  PSHQ
+  POPA
+  BRI int8modLoop
+ int8modDone:
+  ; Add the divisor to Q to get the remainder.
+  CCF
+  PSHQ
+  POPA
+  ADD
+  RET