diff --git a/src/common/eci_string_builder.rs b/src/common/eci_string_builder.rs
index 1ce1fb8..cdf6ca8 100644
--- a/src/common/eci_string_builder.rs
+++ b/src/common/eci_string_builder.rs
@@ -106,9 +106,7 @@ impl ECIStringBuilder {
     pub fn appendECI(&mut self, value: u32) -> Result<(), Exceptions> {
         self.encodeCurrentBytesIfAny();
         let character_set_eci = CharacterSetECI::getCharacterSetECIByValue(value)?;
-        // if (character_set_eci == null) {
-        //   throw FormatException.getFormatInstance();
-        // }
+        
         self.current_charset = CharacterSetECI::getCharset(&character_set_eci);
         Ok(())
     }
diff --git a/src/datamatrix/decoder/decoded_bit_stream_parser.rs b/src/datamatrix/decoder/decoded_bit_stream_parser.rs
index 523b4da..b06fc5d 100644
--- a/src/datamatrix/decoder/decoded_bit_stream_parser.rs
+++ b/src/datamatrix/decoder/decoded_bit_stream_parser.rs
@@ -688,7 +688,7 @@ fn decodeECISegment(bits: &mut BitSource, result: &mut ECIStringBuilder) -> Resu
 
     let secondByte = bits.readBits(8)?;
     if firstByte <= 191 {
-        return result.appendECI(firstByte - 1);
+        return result.appendECI((firstByte - 128) * 254 + 127 + secondByte - 1);
     }
 
     let thirdByte = bits.readBits(8)?;
diff --git a/test_resources/blackbox/datamatrix-1/readerinit.png b/test_resources/blackbox/datamatrix-1/readerinit.png
new file mode 100644
index 0000000..eeb3823
Binary files /dev/null and b/test_resources/blackbox/datamatrix-1/readerinit.png differ
diff --git a/test_resources/blackbox/datamatrix-1/readerinit.result.txt b/test_resources/blackbox/datamatrix-1/readerinit.result.txt
new file mode 100644
index 0000000..b3503a6
--- /dev/null
+++ b/test_resources/blackbox/datamatrix-1/readerinit.result.txt
@@ -0,0 +1,2 @@
+symbologyIdentifier=]d1
+readerInit=true
diff --git a/test_resources/blackbox/datamatrix-1/readerinit.txt b/test_resources/blackbox/datamatrix-1/readerinit.txt
new file mode 100644
index 0000000..32dd1e2
--- /dev/null
+++ b/test_resources/blackbox/datamatrix-1/readerinit.txt
@@ -0,0 +1 @@
+$I
\ No newline at end of file
diff --git a/tests/datamatrix_black_box_test_cases.rs b/tests/datamatrix_black_box_test_cases.rs
index e84eb09..94836ba 100644
--- a/tests/datamatrix_black_box_test_cases.rs
+++ b/tests/datamatrix_black_box_test_cases.rs
@@ -29,10 +29,10 @@ fn data_matrix_black_box1_test_case() {
         rxing::BarcodeFormat::DATA_MATRIX,
     );
     // super("src/test/resources/blackbox/datamatrix-1", new MultiFormatReader(), BarcodeFormat.DATA_MATRIX);
-    tester.add_test(27, 28, 0.0);
-    tester.add_test(21, 26, 90.0);
-    tester.add_test(21, 26, 180.0);
-    tester.add_test(21, 26, 270.0);
+    tester.add_test(27, 27, 0.0);
+    tester.add_test(21, 25, 90.0);
+    tester.add_test(21, 25, 180.0);
+    tester.add_test(21, 25, 270.0);
 
     tester.test_black_box();
 }