BusConstant — bus constant
Ports
| Pin | Type | Description |
|---|---|---|
| OUT | bus (8 bits) | Output: the fixed value (0–255), never changes |
BusConstant has no inputs — the value is fixed in the component's properties when placed.
How It Works
BusConstant always emits the same value regardless of external signals or clock cycles. It is a "nailed-down" number source: the circuit can rely on it at any moment.
Typical example: to always feed the ALU the value 1 as the second operand (incrementing the program counter), connect a BusConstant set to 1 — no extra circuitry needed.
Usage
Constants surround every processor: the 1 for incrementing the ProgramCounter, masks for BusAND/BusOR (for example, 00001111 for the low nibble), base RAM addresses, opcodes for the Decoder.
If the value must change during a test, use a BusInput with a slider. If it is always the same, BusConstant is more reliable: it cannot be nudged by accident.
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