What is it?

For a long time contact card readers worked using a PCSC protocol.

Contact cards include SIM cards, bank cards, Public Key Infrastructure cards, and the like, with actual contacts on the card. Cards like these can be important for logging in to systems, and are even included in some makes of keyboard.

It seems a new CCID protocol now exists, instead of PCSC, and has more options.

This board has two sizes, one of which can be snapped off.

• An ISO7816 card with all 8 contact to slot in to a reader. This can be snapped off. There is even a GPIO to confirm if this is present.
• An ISO7816 slot for a card, with all 8 contacts connected to the above card. Allows monitor of VPP, VCC, RST, I/O. It also allows powering VCC and driving RST and I/O, as needed, with level convertors.
• ESP32-S3-MINI-1-N4-R2 dual processor with 4M flash and 2M SPI RAM, WIFi, etc.
• USB power and device interface for card reader.
• Status LED

Why did you make it?

Whilst I have a card printer with PCSC contract reader, and standalone readers, I have various new SIM card which will not work in my printer. I also have applications for PKI cards that need a reader.

Standard CCID readers seemed a tad more expensive, and I decided a proper dev board would allow more options. For example I have code to work as a keyboard that types the ICCID of an inserted SIM card. We sell SIM cards, and this helps handle the allocation and shipping when the SIMs can no longer go through the printer.

But also, whilst at it, I decided to make a passive monitor. This was mainly to help me develop the reader and SIM ICCID keyboard, and so on, as it allowed me to monitor an industry standard reader and how it worked with a card. But it is also useful to debug protocols that are not so obvious.

What makes it special?

There are boards like this, sold decades ago, and I have one, but with a serial port not a processor. This is better in many ways.

• Can work as emulator for a card. I don't have any code for this yet.
• Can work as passive monitor for card to reader.
• Can work as card reader, with 3.3V (which is within 3V±10%) and 5V power options for card.

Working as reader it can be a USB device and so be a proper CCID Reader. Code is pre-loaded to be a CCID Reader (with some limitations), SIM card ICCID keyboard entry, and passive monitor logging to MQTT. But use your own code to do what you want.

Note

This is not a back-to-back card to reader, which has been used for things like hacking older bank cards by making a reader think a PIN was valid when the card said it was not. It allows passive monitoring of card to reader only - so ideal for diagnostics and development of CCID applications.