8-bit-computer/addrregister.ts

// Address Register component for the LogicSimulator used on the 8-bit-computer
// Copyright (C) 2022 Sascha Nitsch

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.

// eslint-disable-next-line @typescript-eslint/no-unused-vars
class AddrRegister extends BaseComponent {
  private r = 0;
  private R = false;
  private W = false;
  private CLK = false;
  private oldCLK = false;
  constructor(simulator: Simulator, id: string, param: BaseComponentParam) {
    super(simulator, id, param);
    for (let i = 0; i < 8; ++i) {
      this.pins.set('A' + (7 - i), new TriState(this, -40, i * 10 - 80));
      this.pins.set('B' + (7 - i), new TriState(this, -40, i * 10 + 10));
      this.stateMapBool.set('A' + (7 - i), false);
      this.stateMapBool.set('B' + (7 - i), false);
    }
    this.pins.set('R', new TriState(this, 40, 100));
    this.pins.set('W', new TriState(this, 40, 110));
    this.pins.set('CLK', new TriState(this, 40, 80));
    this.pins.set('invCLK', new TriState(this, 40, 90));
    for (let i = 0; i < 16; ++i) {
      this.pins.set('O' + (15 - i), new TriState(this, 40, i * 10 - 80));
      this.stateMapBool.set('O' + (15 - i), false);
    }
  }

  setup(canvas: SVGElement) {
    super.doSetup('addrregister', canvas);
  }

  update(): boolean {
    let i;
    let value;
    // is R set ? then send out to addrbus
    if (this.R) {
      // which register is selected via R3...R0
      value = this.r;
      for (i = 0; i < 16; ++i) {
        this.getPin('O' + i).setBool((value & (1 << i)) > 0 ? true : false);
      }
    }

    const rising = this.CLK && this.oldCLK === false;
    this.oldCLK = this.CLK;
    // is W set ? read from bus on raising clock edge
    if (this.W && rising) {
      this.r =
        this.asint(this.getStateBool('A7'), 32768) +
        this.asint(this.getStateBool('A6'), 16384) +
        this.asint(this.getStateBool('A5'), 8192) +
        this.asint(this.getStateBool('A4'), 4096) +
        this.asint(this.getStateBool('A3'), 2048) +
        this.asint(this.getStateBool('A2'), 1024) +
        this.asint(this.getStateBool('A1'), 512) +
        this.asint(this.getStateBool('A0'), 256) +
        this.asint(this.getStateBool('B7'), 128) +
        this.asint(this.getStateBool('B6'), 64) +
        this.asint(this.getStateBool('B5'), 32) +
        this.asint(this.getStateBool('B4'), 16) +
        this.asint(this.getStateBool('B3'), 8) +
        this.asint(this.getStateBool('B2'), 4) +
        this.asint(this.getStateBool('B1'), 2) +
        this.asint(this.getStateBool('B0'), 1);
    }
    return false;
  }

  io() {
    this.CLK = this.binary(this.getPin('CLK').getAndReset(), true);
    this.getPin('invCLK').getAndReset();
    this.R = this.binary(this.getPin('R').getAndReset(), true);
    this.W = this.binary(this.getPin('W').getAndReset(), true);
    for (let i = 0; i < 8; ++i) {
      this.stateMapBool.set('A' + i, this.binary(this.getPin('A' + i).getAndReset(), true));
      this.stateMapBool.set('B' + i, this.binary(this.getPin('B' + i).getAndReset(), true));
    }
    for (let i = 0; i < 16; ++i) {
      this.stateMapBool.set('O' + i, this.binary(this.getPin('O' + i).getAndReset(), true));
    }
  }
}