diff --git a/kaleid/kernel/sh/shcmds.c b/kaleid/kernel/sh/shcmds.c
index 958495a..d3dd430 100644
--- a/kaleid/kernel/sh/shcmds.c
+++ b/kaleid/kernel/sh/shcmds.c
@@ -141,7 +141,7 @@ error_t CmdDumpATASect(int argc, char **argv, char *cmdline)
 
     IoReadATA(sector, 1, sectNumber);
 
-    while(x < 513) {
+    while(x < 512) {
         KernLog("%C", shcol);
         for (int i = 0; i < step; i++) {
             KernLog("%02x ", (uchar)sector[i+x]);