A cross-platform simulator for the GreenArrays GA144 multi-computer chip.
add some comments
+7
-6
+7
-6
src/f18.zig
+7
-6
src/f18.zig
···
1
-
//! F18A is a 18-bit computer architecture designed by Chuck Moore.
1
+
//! The F18A is an 18-bit computer designed by Chuck Moore.
2
2
3
3
pub const Word = i18;
4
4
···
106
106
};
107
107
/// control and status for communication ports and I/O logic.
108
108
io: Word,
109
-
/// serves as a "program computer"
109
+
/// serves as a "program counter" and extended arithmetic flag
110
110
p: ProgramCounter,
111
111
/// general purpose read/write address or data register
112
112
a: Word,
···
114
114
b: u9,
115
115
/// instruction words containing 1, 2, 3 or 4 opcodes for execution
116
116
i: Word,
117
-
117
+
/// top 64 words are RAM, bottom half are ROM
118
118
mem: [128]Word,
119
-
119
+
// 9 word stack
120
120
return_stack: stack.ReturnStack,
121
+
// 10 word stack
121
122
data_stack: stack.DataStack,
122
-
123
+
// involved in some Extended Arithmetic mode instructions
123
124
carry: u1,
124
125
125
126
state: State = .fetch,
126
-
127
+
// keeps track of current slot to help address decoding
127
128
slot: u2,
128
129
129
130
pub fn step(self: *Computer) void {