Setting up PAT80 Emulator

.gitmodules

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+[submodule "pat80-emulator/z80"]
+	path = pat80-emulator/z80
+	url = git@github.com:algodesigner/z80.git

pat80-emulator/.gitignore

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+pat80emu

pat80-emulator/Makefile

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+build:
+	gcc -g -o pat80emu z80/console.c z80/z80.c main.c
+clean:
+	rm -rf main
+all: clean build

pat80-emulator/README.md

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+# PAT80 Emulator
+Uses algodesigner's Z80 emulator (see submodule in z80 folder).
+Instances the Z80 object (representing the CPU) and:
+- intercepts all memory access and returns the corresponding rom value (read from rom file) if PC is in first 32k of memory (TODO)
+- intercepts all memory access and stops execution returning error if trying to write to first 32k of memory (TODO)
+
+## Usage
+Build with `make all`
+Run with `./pat80emu`

pat80-emulator/main.c

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+#include <stdio.h>
+#include "z80/z80.h"
+
+/*
+ * The intercept function is invoked on each and every CPU instruction. It
+ * quits the simulation when the PC register reaches address #0005 by changing
+ * the virtual CPU status.
+ */
+static void intercept(void *ctx)
+{
+    z80 *cpu = ctx;
+    if (PC == 5) {
+        puts("\nReached address: 5, terminating the simulation...");
+        cpu->status = 1;
+    }
+}
+
+int main(int argc, char *argv[])
+{
+    /*
+     * Instantiate the CPU, activate the debug mode, set the intercept
+     * function and run the virtual CPU until the termination criteria
+     * set by the intercept function, if any, are met.
+     */
+    z80 *cpu = z80_new();
+    cpu->debug = 1;
+
+    // TODO: Copy rom to first 32k CPU memory
+    _RamWrite(0x03, 0x76);  // As an example, here is how to set HALT at posizion 0x03. Use a loop to copy memory from a PAT80 OS rom file.
+
+    z80_set_intercept(cpu, cpu, intercept);
+    z80_run(cpu);
+    z80_destroy(cpu);
+}

pat80-emulator/z80

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+Subproject commit 80df33fc873e8eb374c1fcb33458a1b7220d20db