Code 128 條碼容許輸入 ASCII 碼為 0 至 127 的字元，可是由於鍵盤只能鍵入一般的英文字母、數字和標點符號，所以不能直接輸入全部可用的字元。為了解決輸入特殊字元的困惑，便要使用逸出序列（Escape Sequence）的方式。這個逸出序列看來好像很複雜，但其實十分簡單，只要按照下面的步驟練習，很快便能掌握。
Code 39 條碼有兩種狀態，基本狀態只接受半形大寫英文字母、數字、空格和-.$/+%，而擴充狀態則容許輸入 ASCII 碼為 0 至 127 的字元，可是-.$/+%卻要改用逸出碼表示，並且須條碼掃描器支援擴充狀態才能解讀。不過現在只介紹如何輸入逸出序列，請按照下面的步驟練習。
| ASCII碼 | Code 39逸出碼 | Code 128逸出碼 | 縮寫 | 意義 |
|---|---|---|---|---|
| 00 | %U | ^` | NUL | Null |
| 01 | $A | ^a | SOH | Start of Heading |
| 02 | $B | ^b | STX | Start of Text |
| 03 | $C | ^c | ETX | End of Text |
| 04 | $D | ^d | EOT | End of Transmission |
| 05 | $E | ^e | ENO | Enquiry |
| 06 | $F | ^f | ACK | Acknowledgment |
| 07 | $G | ^g | BEL | Bell |
| 08 | $H | ^h | BS | Backspace |
| 09 | $I | ^i | HT | Horizontal Tab |
| 0A | $J | ^j | LF | Line Feed |
| 0B | $K | ^k | VT | Vertical Tab |
| 0C | $L | ^l | FF | Form Feed |
| 0D | $M | ^m | CR | Carriage Return |
| 0E | $N | ^n | S0 | Shift Out |
| 0F | $O | ^o | S1 | Shift In |
| 10 | $P | ^p | DLE | Data Link Escape |
| 11 | $Q | ^q | DC1 | Device Control 1 (XON) |
| 12 | $R | ^r | DC2 | Device Control 2 (AUXON) |
| 13 | $S | ^s | DC3 | Device Control 3 (XOFF) |
| 14 | $T | ^t | DC4 | Device Control 4 (AUXOFF) |
| 15 | $U | ^u | NAK | Negative Acknowledgment |
| 16 | $V | ^v | SYN | Synchronous file |
| 17 | $W | ^w | ETB | End of Transmission Block |
| 18 | $X | ^x | CAN | Cancel |
| 19 | $Y | ^y | EM | End of Medium |
| 1A | $Z | ^z | SUB | Substitute |
| 1B | %A | ^{ | ESC | Escape |
| 1C | %B | ^| | FS | File (or Form) Separator |
| 1D | %C | ^} | GS | Group Separator |
| 1E | %D | ^~ | RS | Record Separator |
| 1F | %E | ^_ | US | Unit Separator |
| 7F | %T | ^< | DEL | Delete |
| - | - | ^1 | FNC 1 | Function 1 |
| - | - | ^2 | FNC 2 | Function 2 |
| - | - | ^3 | FNC 3 | Function 3 |
| - | - | ^4 | FNC 4 | Function 4 |
| 21 | /A | - | ! | ! |
| 22 | /B | - | " | " |
| 23 | /C | - | # | # |
| 24 | /D | - | $ | $ |
| 25 | /E | - | % | % |
| 26 | /F | - | & | & |
| 27 | /G | - | ' | ' |
| 28 | /H | - | ( | ( |
| 29 | /I | - | ) | ) |
| 2A | /J | - | * | * |
| 2B | /K | - | + | + |
| 2C | /L | - | , | , |
| 2F | /O | - | / | / |
| 3A | /Z | - | : | : |
| 3B | %F | - | ; | ; |
| 3C | %G | - | < | < |
| 3D | %H | - | = | = |
| 3E | %I | - | > | > |
| 3F | %J | - | ? | ? |
| 40 | %V | - | @ | @ |
| 5B | %K | - | [ | [ |
| 5C | %L | - | \ | \ |
| 5D | %M | - | ] | ] |
| 5E | %N | - | ^ | ^ |
| 5F | %O | - | _ | _ |
| 60 | %W | - | ` | ` |
| 61 | +A | - | a | a |
| 62 | +B | - | b | b |
| 63 | +C | - | c | c |
| 64 | +D | - | d | d |
| 65 | +E | - | e | e |
| 66 | +F | - | f | f |
| 67 | +G | - | g | g |
| 68 | +H | - | h | h |
| 69 | +I | - | i | i |
| 6A | +J | - | j | j |
| 6B | +K | - | k | k |
| 6C | +L | - | l | l |
| 6D | +M | - | m | m |
| 6E | +N | - | n | n |
| 6F | +O | - | o | o |
| 70 | +P | - | p | p |
| 71 | +Q | - | q | q |
| 72 | +R | - | r | r |
| 73 | +S | - | s | s |
| 74 | +T | - | t | t |
| 75 | +U | - | u | u |
| 76 | +V | - | v | v |
| 77 | +W | - | w | w |
| 78 | +X | - | x | x |
| 79 | +Y | - | y | y |
| 7A | +Z | - | z | z |
| 7B | %P | - | { | { |
| 7C | %Q | - | | | | |
| 7D | %R | - | } | } |
| 7E | %S | - | ~ | ~ |
另可參考 Grand Zebu 的網頁