STMicroelectronics AN1527 Application Note

About this manual

This document describes a firmware implementation developed by STMicroelectronics for a USB Smart Card Reader using the ST7SCR microcontroller. The firmware is designed to work with the associated Smart Card Reader board available from the manufacturer.

The implementation is divided into four main parts: USB management, Chip Card Interface Device (CCID) implementation, Interface Device (IFD) implementation, and 7816 UART Smartcard Interface (CRD) management. The main loop polls USB transactions using a state machine process to handle Bulk-in and Bulk-out messages.

What's inside

• Introduction
• CCID Implementation
• IFD Implementation
• Function Description
• USB Management
• Chip Card Interface Device
• Interface Device
• UART Smartcard Interface

Frequently asked questions

What is the maximum size of the message buffer used by the CCID implementation?

The CCID implementation uses a 271-byte buffer for all messages.

How many bytes are allocated for the message header?

The message header is fixed at 10 bytes.

What is the maximum data size available for messages?

The data portion of the message can be up to 261 bytes.