diff --git a/src/commonMain/kotlin/net.sergeych.bintools/simple_codecs.kt b/src/commonMain/kotlin/net.sergeych.bintools/simple_codecs.kt
index ae0c76e..29db24f 100644
--- a/src/commonMain/kotlin/net.sergeych.bintools/simple_codecs.kt
+++ b/src/commonMain/kotlin/net.sergeych.bintools/simple_codecs.kt
@@ -102,7 +102,13 @@ fun ByteArray.toDumpLines(wide: Boolean = false): List<String> {
         val max: Int = kotlin.math.min(size, from + lineSize)
         while (from < max) {
             val ch = this[from++].toInt()
-            if (ch >= ' '.code && ch < 127) b.append(ch.toChar()) else b.append('.')
+            when {
+                ch == ' '.code -> b.append('\u25AD')
+                (ch > ' '.code && ch < 127) -> b.append(ch.toChar())
+                else -> b.append('.')
+            }
+            if( (from % lineSize) == lineSize/2 )
+                b.append("\u250A")
         }
         val remainder = from % lineSize
         if (remainder > 0) {
@@ -128,12 +134,14 @@ fun ByteArray.toDumpLines(wide: Boolean = false): List<String> {
                 line.append(' ')
             }
             line!!.append((this[i].toUByte()).encodeToHex(2))
+            if( i == lineSize/2) line.append(" \u250A")
             line.append(' ')
         }
         if (line != null) {
             val l = size
             var fill = lineSize - l % lineSize
             if (fill < lineSize) while (fill-- > 0) line.append("   ")
+            line.append("  ")
             val index = l - l % lineSize
             line.append(dumpChars(if (index < l) index else l - lineSize))
             lines.add(line.toString())