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authorWlodekM <[email protected]>2025-04-02 19:42:29 +0300
committerWlodekM <[email protected]>2025-04-02 19:42:29 +0300
commit7d5b4d78bf24ebcae4bd8957e91aba2541a26686 (patch)
tree44c2c34e0d4df59518343bb8e3e0b9fb3ae83614 /instructions
parent13e92fe6a4ac7cbaa58f7f03b082e1afcc57cffc (diff)
some more
Diffstat (limited to 'instructions')
-rw-r--r--instructions/LDX.ts9
-rw-r--r--instructions/LDY.ts9
-rw-r--r--instructions/LSR.ts23
-rw-r--r--instructions/NOP.ts6
4 files changed, 47 insertions, 0 deletions
diff --git a/instructions/LDX.ts b/instructions/LDX.ts
new file mode 100644
index 0000000..86c0859
--- /dev/null
+++ b/instructions/LDX.ts
@@ -0,0 +1,9 @@
+import type The65c02 from "../65c02.ts";
+
+export default function (this: The65c02, mode: string) {
+    const addr = this.getAddr(mode);
+    this.io.address.set(addr);
+    this.read();
+    this.flagZN(this.io.data.num())
+    this.regX.set(this.io.data.num())
+}
\ No newline at end of file
diff --git a/instructions/LDY.ts b/instructions/LDY.ts
new file mode 100644
index 0000000..6fb0232
--- /dev/null
+++ b/instructions/LDY.ts
@@ -0,0 +1,9 @@
+import type The65c02 from "../65c02.ts";
+
+export default function (this: The65c02, mode: string) {
+    const addr = this.getAddr(mode);
+    this.io.address.set(addr);
+    this.read();
+    this.flagZN(this.io.data.num())
+    this.regY.set(this.io.data.num())
+}
\ No newline at end of file
diff --git a/instructions/LSR.ts b/instructions/LSR.ts
new file mode 100644
index 0000000..61adadb
--- /dev/null
+++ b/instructions/LSR.ts
@@ -0,0 +1,23 @@
+import type The65c02 from "../65c02.ts";
+
+export default function (this: The65c02, mode: string) {
+    if (mode == 'implicit') {
+        const mem = this.regA.num();
+        const result = mem >> 1;
+        this.negative = (result & 128) != 0
+        this.zero = result == 0
+        this.carry = (mem & 1) != 0
+        this.regA.set(result & 0xFF);
+    } else {
+        const addr = this.getAddr(mode)
+        this.io.address.set(addr);
+        this.read()
+        const mem = this.io.data.num();
+        const result = mem >> 1;
+        this.negative = (result & 128) != 0
+        this.zero = result == 0
+        this.carry = (mem & 1) != 0
+        this.io.data.set(result & 0xFF);
+        this.write()
+    }
+}
\ No newline at end of file
diff --git a/instructions/NOP.ts b/instructions/NOP.ts
new file mode 100644
index 0000000..e266938
--- /dev/null
+++ b/instructions/NOP.ts
@@ -0,0 +1,6 @@
+import type The65c02 from "../65c02.ts";
+
+export default function (this: The65c02) {
+    this.programCounter.increment();
+    this.programCounter.increment();
+}
\ No newline at end of file