diff --git a/src/system/disk.1224 b/src/system/disk.1225
similarity index 99%
rename from src/system/disk.1224
rename to src/system/disk.1225
index 285c58ba..5b0f0250 100755
--- a/src/system/disk.1224
+++ b/src/system/disk.1225
@@ -3120,6 +3120,7 @@ QRCBUF:	BLOCK 2000
 ;VARIABLES FOR DEC RH10 DISK CONTROL
 
 IFN RH10P,[
+IFN KA10P, QIOWD: BLOCK 2
 QCHPRG:	0	;DATA TRANSFER COMMAND
 QCHPGA:	0	;ADDRESS (CYL IN LH, TRACK-SECTOR IN RH)
 NCSHI:	0	;NUMBER OF CACHE INVALIDATES