PyApduTool for JavaCard – The Complete Guide 2026

[Student]

(From real usage in JCIDE/JCKit – pyApduTool is the GUI APDU tool bundled with JavaCardOS JCIDE for sending commands to JavaCards)

What is PyApduTool? pyApduTool is a Python-based GUI tool from JavaCardOS (javacardos.com) for communicating with JavaCards via PC/SC readers. It allows:

• Sending APDU commands
• Executing scripts
• Installing/deleting applets
• Debugging ISO14443/MIFARE
• Managing GlobalPlatform cards

It’s part of JCIDE (Java Card Integrated Development Environment) and works with simulators or real cards.

2025 Status: Still actively used in JavaCard development – latest JCIDE includes pyApduTool v5.0+.

Step-by-Step Setup & Usage (Tested December 2025)​

Step 1 – Download & Install JCIDE (Includes pyApduTool)

1. Go to javacardos.com → Download JCIDE (free registration required)
2. Extract ZIP → run JCIDE.exe (Windows) or JCIDE.jar (cross-platform)
3. pyApduTool is in tools/pyApduTool folder

Alternative: Standalone pyApduTool from JavaCardOS forum (requires JCIDE license).

Step 2 – Setup Reader / Simulator

1. Connect PC/SC reader (ACR122U, OMNIKEY, etc.)
2. Or use JCIDE simulator:
   • JCIDE → Simulator → “Default” or “A40CR” (contactless)
3. Start pyApduTool.exe from JCIDE tools folder

Step 3 – Connect to Card

1. In pyApduTool GUI:
   • Reader dropdown → select your reader or “Simulator Contact” / “Simulator Contactless”
   • Click Connect
2. Successful connection shows ATR:
   

   ATR: 3B F9 18 00 00 81 31 FE 45 4A 43 4F 50 76 32 34 32 52 33 B7

Step 4 – Basic Commands
Select AID (example Visa):

1. CLA: 00
2. INS: A4
3. P1: 04
4. P2: 00
5. Lc: 07
6. Data: A0000000031010
7. Le: 00
8. Click Send
9. Response: 9000 = success

Get Processing Options (GPO):

1. CLA: 80
2. INS: A8
3. P1: 00
4. P2: 00
5. Lc: 02
6. Data: 8300
7. Le: 00
8. Send → get response with tags

Step 5 – Install Applet (CAP File)

1. Load CAP → browse to .cap file
2. Authenticate (default keys 404142...4F)
3. Click Install
4. Select package + applet AID
5. Success: 9000

Step 6 – Execute APDU Script

1. Script tab → load .scr file or paste commands
2. Example script:
   

   00A4040007A000000003101000
   80A8000002830000
   00B2010C00

3. Run script → see all responses

Step 7 – Advanced Features

• GlobalPlatform mode – install/delete packages
• MIFARE debug – with R502 SPY reader
• Error lookup – SW codes

Real Example Session (JCOP 160K v2.4.2 R3 – Visa Applet)​

1. Connect → ATR shown
2. Select PPSE:
   • Command: 00A404000E325041592E5359532E444446303100
   • Response: Lists Visa AID
3. Select Visa:
   • 00A4040007A000000003101000
   • Response: 9000
4. GPO:
   • 80A8000002830000
   • Response: PDOL data
5. Read Record:
   • 00B2010C00 → PAN + expiry

Bottom Line – December 2025​

pyApduTool is the best GUI APDU tool bundled with JCIDE – perfect for JavaCard testing, applet install, and debugging.

Get it from javacardos.com (JCIDE download).

For command-line: Use GlobalPlatform Pro or pyResMan.

Stay safe – use for legitimate development only.

Your choice.