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--- microvax_mem_test [2026/04/29 01:28] – created admin
+++ microvax_mem_test [2026/04/29 01:29] (current) – admin
@@ Line 7: / Line 7: @@
 <code>python vax_mem_full.py</code>
+Script:
+<code>
+import serial
+import time
+import re
+# Increase timeout and use a slightly slower baud rate if 9600 is flaky,
+# but 9600 is usually standard.
+ser = serial.Serial('/dev/ttyS0', 9600, timeout=1)
+def vax_io(cmd):
+    # 1. Clear the buffer so we don't read old garbage
+    ser.reset_input_buffer()
+    # 2. Send the command with a Carriage Return
+    ser.write(f"{cmd}\r".encode())
+    # 3. Wait for the VAX to finish. We look for the '>>>' prompt.
+    timeout = time.time() + 2  # 2 second safety timeout
+    full_resp = ""
+    while ">>>" not in full_resp:
+        if ser.in_waiting > 0:
+            full_resp += ser.read(ser.in_waiting).decode(errors='ignore')
+        if time.time() > timeout:
+            break
+        time.sleep(0.05)
+    return full_resp
+def test_onboard_full_map():
+    start = 0x00300000
+    end = 0x003FFFFF
+    error_count = 0
+    print(f"--- Mapping Entire Onboard RAM (4MB) ---")
+    # We'll use a slightly larger step (e.g., 1KB) if you want a fast map,
+    # or keep it at 4 to check every single longword.
+    for addr in range(start, end, 4):
+        addr_hex = f"{addr:08X}"
+        # Test pattern: All zeros then all ones
+        for pat in [0x00000000, 0xFFFFFFFF, 0xAAAAAAAA, 0x55555555]:
+            pat_hex = f"{pat:08X}"
+            vax_io(f"D /L /P /U {addr_hex} {pat_hex}")
+            resp = vax_io(f"E /L /P /U {addr_hex}")
+            match = re.search(r"P\s+[0-9A-F]+\s+([0-9A-F]+)", resp, re.IGNORECASE)
+            if match:
+                received_val = match.group(1).upper()
+                if received_val != pat_hex:
+                    error_count += 1
+                    print(f"\n[!] ERROR at {addr_hex}")
+                    print(f"    Expected: {pat_hex} | Recv: {received_val}")
+                    # If we get too many errors, the board might be totally dead
+                    if error_count > 100:
+                        print("\n[!!!] Too many errors! Likely a controller or bus failure.")
+                        return
+        if addr % 0x1000 == 0:
+            print(f"Mapping... {addr_hex} (Errors found: {error_count})", end='\r')
+    print(f"\nScan Complete. Total errors logged: {error_count}")
+# Clear the screen on the VAX first
+vax_io("\r")
+test_onboard_full_map()
+</code>