Started working on assembler.

Author: ExpandingMan

src/Sim6502.jl

@@ -19,5 +19,6 @@ include("boilerplate.jl")
 include("instructions.jl")
 include("chipset.jl")
 include("opcodes.jl")
+include("assembler.jl")
 
 end # module

src/boilerplate.jl

@@ -131,11 +131,14 @@ end
 
 
 macro opdef(opname::Symbol, defblock::Expr)
-    @capture(defblock, begin defs__ end)
-    defs = [tuple(ex.args...) for ex ∈ defs]
-    funcdefs = [opdef(d[1], opname, d[2]) for d ∈ defs]
-    dictries = [opdict(d[2], d[3], d[4]) for d ∈ defs]
-    assemblies = [assemblydict(opname, d[1], d[2]) for d ∈ defs]
+    if @capture(defblock, begin defs__ end)
+        defs = [ex.args for ex ∈ defs]
+        funcdefs = [opdef(d[1], opname, d[2]) for d ∈ defs]
+        dictries = [opdict(d[2], d[3], d[4]) for d ∈ defs]
+        assemblies = [assemblydict(opname, d[1], d[2]) for d ∈ defs]
+    else
+        throw(AssertionError("Improper op definition for $opname."))
+    end
     esc(quote
         $(funcdefs...)
         $(dictries...)

src/instructions.jl

@@ -477,11 +477,11 @@ export clc!, cld!, cli!, clv!, sec!, sed!, sei!
 #===================================================================================================
     <system functions>
 ===================================================================================================#
-# TODO this will require some special handling
 brk!(c::CPU) = status!(c, :B, true)
 
 nop!(c::CPU) = ()
 
+# TODO this is likely fucked up
 # __NOTE!!__ that PC is also incremented the normal way afterwards from reading the instruction
 function rti!(c::CPU, m::Memory)
     ptr = stackpointer(c) + 0x01  # are you sure about this?
@@ -490,7 +490,7 @@ function rti!(c::CPU, m::Memory)
     pc_small = deref(ptr, m)
     ptr = ptr + 0x01
     pc_big = deref(ptr, m)
-    c.PC = 0x0100*pc_big + pc_small
+    c.PC = bincat(pc_small, pc_big)
     c.SP += 0x03  # not completely confident in this either
 end
 

src/opcodes.jl

@@ -32,9 +32,18 @@ end
 # this doesn't do the sleeping
 function op!(cs::Chipset)
     exe!, nbytes, ncycles = OPCODES[deref(Π(cs.cpu.PC), cs.ram)]
+    exe!(cs)
     cs.cpu.PC += nbytes
     cs.clock += ncycles
-    exe!(cs), nbytes, ncycles
+    nbytes, ncycles
+end
+
+# TODO eventually this should employ timing
+function run!(cs::Chipset)
+    while !cs.cpu.flags.B
+        op!(cs)
+        println(cs)
+    end
 end
 
 export op!, tick!
@@ -59,7 +68,9 @@ const OPCODES = Vector{Tuple{OpFunc,Int,Int}}(N_OPCODES)
 const ASSEMBLY_DICT = Dict{Tuple{String,Symbol},UInt8}(); sizehint!(ASSEMBLY_DICT, N_OPCODES)
 
 # format is
-#    mode, opcode, nbytes, ncycles
+#    mode, opcode, nbytes, ncycles, (increment)
+#
+# the last arg is optional and tells it whether or not to increment the instruction pointer
 
 # we treat "Accumulator" mode as "Implicit"
 
@@ -298,10 +309,92 @@ end
     AbsoluteX, 0x7e, 3, 7
 end
 
-# TODO haven't decided how to do this yet!
+# note that these get 0's because they don't increment the instruction pointer
 @opdef jmp! begin
-    Immediate, 0x4c, 3, 3
-    Absolute,  0x6c, 3, 5
+    Immediate, 0x4c, 0, 3
+    Absolute,  0x6c, 0, 5
+end
+
+@opdef jsr! begin
+    Immediate, 0x20, 0, 6
+end
+
+# TODO not sure if implicit works with cpu and ram arguments
+@opdef rts! begin
+    Implicit,  0x60, 0, 6
+end
+
+# TODO check if instruction pointer is handled correctly in branches
+@opdef bcc! begin
+    Immediate, 0x90, 2, 2 
+end
+
+@opdef bcs! begin
+    Immediate, 0xb0, 2, 2
+end
+
+@opdef beq! begin
+    Immediate, 0xf0, 2, 2
+end
+
+@opdef bmi! begin
+    Immediate, 0x30, 2, 2
+end
+
+@opdef bne! begin
+    Immediate, 0xd0, 2, 2  
+end
+
+@opdef bpl! begin
+    Immediate, 0x10, 2, 2
+end
+
+@opdef bvc! begin
+    Immediate, 0x50, 2, 2
+end
+
+@opdef bvs! begin
+    Immediate, 0x70, 2, 2
+end
+
+@opdef clc! begin
+    Implicit,  0x18, 1, 2
+end
+
+@opdef cld! begin
+    Implicit,  0xd8, 1, 2
+end
+
+@opdef cli! begin
+    Implicit,  0x58, 1, 2
+end
+
+@opdef clv! begin
+    Implicit,  0xb8, 1, 2
+end
+
+@opdef sec! begin
+    Implicit,  0x38, 1, 2
+end
+
+@opdef sed! begin
+    Implicit,  0xf8, 1, 2
+end
+
+@opdef sei! begin
+    Implicit,  0x78, 1, 2
+end
+
+@opdef brk! begin
+    Implicit,  0x00, 1, 7
+end
+
+@opdef nop! begin
+    Implicit,  0xea, 1, 2
+end
+
+@opdef rti! begin
+    Implicit,  0x40, 1, 6
 end
 #===================================================================================================
     </opcodes>

test/opcodes.jl

@@ -28,7 +28,17 @@ function makechipset()
     cs
 end
 
-# TODO investigate allocs!!!
+
+function showstates()
+    cs = makechipset()
+
+    @p op!(cs)
+    @p op!(cs)
+    @p op!(cs)
+
+    cs
+end
+
 
 function runbenches()
     ref = @benchmarkable begin
@@ -47,4 +57,4 @@ function runbenches()
 end
 
 
-ref, b = runbenches()
+# ref, b = runbenches()