ZX Spectrum de coronavírus e paus (na verdade, não realmente)

• 14 15 , 16 , , 000, 0 ( ), Y0 (15 ). , .
• 14 , 15 — , 16 , 32 , 001, 1 , Y1 (14 ). , 16 , .
• 14 , 15 — , - 32 48 , 010, Y2 (13 ). , .
• Se as duas linhas (A14 e A15) estiverem ativas, o processador acessa os 16 KiB de memória principais, de 48 a 64 KiB, não temos, portanto o pino Y3 (12º pino) também está no ar.

// CPU defines
#define CPU_CLOCK_PIN 2
#define CPU_RESET_PIN 3

// RAM defines
#define RAM_OUTPUT_ENABLE_PIN 4
#define RAM_WRITE_ENABLE_PIN 5
#define RAM_CHIP_ENABLE_PIN 6
#define RAM_BUFFER_PIN 7

// Shift Register defines
#define SR_DATA_PIN 8
#define SR_OUTPUT_ENABLE_PIN 9
#define SR_LATCH_PIN 10
#define SR_CLOCK_PIN 11

//////////////////////////////////////////////////////////////////////////

void setup() {
  // All CPU and RAM control signals need to be configured as inputs by default
  // and only changed to outputs when used.
  // Shift register control signals may be preconfigured

  // CPU controls seetup
  DDRC = B00000000;
  pinMode(CPU_CLOCK_PIN, INPUT);
  pinMode(CPU_RESET_PIN, INPUT);

  // RAM setup
  pinMode(RAM_WRITE_ENABLE_PIN, INPUT);
  pinMode(RAM_OUTPUT_ENABLE_PIN, INPUT);
  pinMode(RAM_CHIP_ENABLE_PIN, INPUT);
  pinMode(RAM_BUFFER_PIN, OUTPUT);
  digitalWrite(RAM_BUFFER_PIN, LOW);

  // SR setup
  pinMode(SR_LATCH_PIN, OUTPUT);
  pinMode(SR_CLOCK_PIN, OUTPUT);
  pinMode(SR_DATA_PIN, OUTPUT);
  pinMode(SR_OUTPUT_ENABLE_PIN, OUTPUT);
  digitalWrite(SR_OUTPUT_ENABLE_PIN, HIGH); // active low

  // common setup
  Serial.begin(9600);
  Serial.println("Hello");
}// setup

//////////////////////////////////////////////////////////////////////////

void shiftReadValueFromAddress(uint16_t address, uint8_t *value) {
  // disable RAM output
  pinMode(RAM_WRITE_ENABLE_PIN, OUTPUT);
  digitalWrite(RAM_WRITE_ENABLE_PIN, HIGH); // active low
  pinMode(RAM_OUTPUT_ENABLE_PIN, OUTPUT);
  digitalWrite(RAM_OUTPUT_ENABLE_PIN, HIGH); // active low
  // set address
  digitalWrite(SR_LATCH_PIN, LOW);
  shiftOut(SR_DATA_PIN, SR_CLOCK_PIN, MSBFIRST, address>>8); 
  shiftOut(SR_DATA_PIN, SR_CLOCK_PIN, MSBFIRST, address);  
  digitalWrite(SR_LATCH_PIN, HIGH);
  digitalWrite(SR_OUTPUT_ENABLE_PIN, LOW); // active low
  // write value to RAM
  digitalWrite(RAM_OUTPUT_ENABLE_PIN, LOW); // active low
  delay(1);
  DDRC = B00000000;
  *value = PINC;
  digitalWrite(RAM_OUTPUT_ENABLE_PIN, HIGH); // active low
  // disable SR
  digitalWrite(SR_OUTPUT_ENABLE_PIN, HIGH); // active low
  pinMode(RAM_WRITE_ENABLE_PIN, INPUT);
  pinMode(RAM_OUTPUT_ENABLE_PIN, INPUT);
}// shiftWriteValueToAddress

//////////////////////////////////////////////////////////////////////////

void runClock(uint32_t cycles) {
  uint32_t currCycle = 0;
  pinMode(CPU_CLOCK_PIN, OUTPUT);
  while(currCycle < cycles) {
    digitalWrite(CPU_CLOCK_PIN, HIGH);
    digitalWrite(CPU_CLOCK_PIN, LOW);
    currCycle++;
  }
  pinMode(CPU_CLOCK_PIN, INPUT);
}// runClock

//////////////////////////////////////////////////////////////////////////

void trySpectrum() {
  pinMode(RAM_WRITE_ENABLE_PIN, INPUT);
  pinMode(RAM_OUTPUT_ENABLE_PIN, INPUT);
  pinMode(CPU_RESET_PIN, OUTPUT);
  digitalWrite(CPU_RESET_PIN, LOW);
  runClock(30);
  digitalWrite(CPU_RESET_PIN, HIGH);
  runClock(12500000);
}// trySpectrum

//////////////////////////////////////////////////////////////////////////

void readDisplayLines() {
  uint8_t value;
  digitalWrite(RAM_BUFFER_PIN, HIGH);
  pinMode(RAM_CHIP_ENABLE_PIN, OUTPUT);
  digitalWrite(RAM_CHIP_ENABLE_PIN, LOW);
  for(uint16_t i=16384; i<16384+6144;i++) {
    shiftReadValueFromAddress(i, &value);
    Serial.println(value);
  }
  pinMode(RAM_CHIP_ENABLE_PIN, INPUT);
}// readDisplayLines

//////////////////////////////////////////////////////////////////////////

void loop() {
  trySpectrum();
  Serial.println("Hope we are ok now. Please set up memory for reading");
  delay(40000);
  Serial.println("Reading memory");
  readDisplayLines();
  Serial.println("Done");
  delay(100000);
}// loop

// CPU defines
#define CPU_CLOCK_PIN 2 -  2     6  ( )
#define CPU_RESET_PIN 3 -  3     26  (RESET)

// RAM defines
#define RAM_OUTPUT_ENABLE_PIN 4 -  4     22  (OE)
#define RAM_WRITE_ENABLE_PIN 5 -  5    .     .
#define RAM_CHIP_ENABLE_PIN 6 -  6     .        ,        .   - ,   -  .   ,   .
#define RAM_BUFFER_PIN 7 -  ,    6,    .

// Shift Register defines
#define SR_DATA_PIN 8   -  8     14 "" 595.        9 ,     .
#define SR_OUTPUT_ENABLE_PIN 9 -   13  595
#define SR_LATCH_PIN 10 -   12  595
#define SR_CLOCK_PIN 11 -   11  595.

#include "stdafx.h"
#include <windows.h>
#include <stdint.h>
#include <stdio.h>

LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
uint8_t *scrData;

VOID OnPaint(HDC hdc) {
	size_t arrSize = 6144;//sizeof(scrData) / sizeof(scrData[0]);
	//int currRow = 0, currX = 0, currBlock = 0, currY = 0, currBase = 0;
	for (size_t arrPos = 0; arrPos < arrSize; arrPos++) {
		int blockPos = arrPos % 2048;
		int currBase = (blockPos % 256) / 32;
		int currX = blockPos % 32;
		int currBlock = arrPos / 2048;
		int currRow = blockPos / 256;
		int currY = currBlock * 64 + currBase * 8 + currRow;
		for (int trueX = 0; trueX < 8; trueX++) {
			char r = ((scrData[arrPos] >> trueX) & 1)*255;
			SetPixel(hdc, currX * 8 + (8-trueX), currY, RGB(r, r, r));
		}
	}
}

void loadData() {
	FILE *file;
	errno_t err;
	if ((err = fopen_s(&file, "data.txt", "r"))) {
		MessageBox(NULL, L"Unable to oopen the file", L"Error", 1);
	}
	scrData = (uint8_t*)malloc(6144);
	int currDataPos = 0;
	char buffer[256];
	char currChar = 0;
	int currLinePos = 0;
	while (currChar != EOF) {
		currChar = getc(file);
		buffer[currLinePos++] = currChar;
		if (currChar == '\n') {
			buffer[currLinePos] = 0;
			scrData[currDataPos++] = (uint8_t)atoi(buffer);
			currLinePos = 0;
		}
	}
	fclose(file);
}

INT WINAPI WinMain(HINSTANCE hInstance, HINSTANCE, PSTR, INT iCmdShow) {
	HWND                hWnd;
	MSG                 msg;
	WNDCLASS            wndClass;
	wndClass.style = CS_HREDRAW | CS_VREDRAW;
	wndClass.lpfnWndProc = WndProc;
	wndClass.cbClsExtra = 0;
	wndClass.cbWndExtra = 0;
	wndClass.hInstance = hInstance;
	wndClass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
	wndClass.hCursor = LoadCursor(NULL, IDC_ARROW);
	wndClass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
	wndClass.lpszMenuName = NULL;
	wndClass.lpszClassName = TEXT("GettingStarted");
	RegisterClass(&wndClass);
	hWnd = CreateWindow(
		TEXT("GettingStarted"),   // window class name
		TEXT("Getting Started"),  // window caption
		WS_OVERLAPPEDWINDOW,      // window style
		CW_USEDEFAULT,            // initial x position
		CW_USEDEFAULT,            // initial y position
		CW_USEDEFAULT,            // initial x size
		CW_USEDEFAULT,            // initial y size
		NULL,                     // parent window handle
		NULL,                     // window menu handle
		hInstance,                // program instance handle
		NULL);                    // creation parameters
	loadData();
	ShowWindow(hWnd, iCmdShow);
	UpdateWindow(hWnd);
	while (GetMessage(&msg, NULL, 0, 0)) {
		TranslateMessage(&msg);
		DispatchMessage(&msg);
	}
	return msg.wParam;
}  // WinMain

LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam) {
	HDC          hdc;
	PAINTSTRUCT  ps;
	switch (message) {
	case WM_PAINT:
		hdc = BeginPaint(hWnd, &ps);
		OnPaint(hdc);
		EndPaint(hWnd, &ps);
		return 0;
	case WM_DESTROY:
		PostQuitMessage(0);
		return 0;
	default:
		return DefWindowProc(hWnd, message, wParam, lParam);
	}
} // WndProc