The ST7SCR and ST7FSCR devices are members of the ST7 microcontroller family designed for USB applications. All devices are based on a common industry-standard 8-bit core, featuring an enhanced instruction set.The ST7SCR ROM devices are factory-programmed and are not reprogrammable.The ST7FSCR versions feature dual-voltage Flash memory with Flash Programming capability.They operate at a 4 MHz external oscillator frequency.Under software control, all devices can be placed in WAIT or HALT mode, reducing power consumption when the application is in idle or stand-by state.The enhanced instruction set and addressing modes of the ST7 offer both power and flexibility to software developers, enabling the design of highly efficient and compact application code. In addition to standard 8-bit data management, all ST7 microcontrollers feature true bit manipulation, 8×8 unsigned multiplication and indirect addressing modes.
Memories
Up to 16 Kbytes of ROM or High Density Flash (HDFlash) program memory with read/write protection, HDFlash In-Circuit and In-Application Programming. 100 write/erase cycles guaranteed, data retention: 40 years at 55°C
Up to 768 bytes of RAM including up to 128 bytes stack and 256 bytes USB buffer
Clock, reset and supply management
Low voltage reset
2 power saving modes: Halt and Wait modes
PLL for generating 48 MHz USB clock using a 4 MHz crystal
Interrupt management
Nested Interrupt controller
USB (Universal Serial Bus) interface
256-byte buffer for full speed bulk, control and interrupt transfer types compliant with USB specification (version 2.0)
On-Chip 3.3V USB voltage regulator and transceivers with software power-down
7 USB endpoints:One 8-byte Bidirectional Control EndpointOne 64-byte In Endpoint,One 64-byte Out EndpointFour 8-byte In Endpoints
35 or 4 I/O ports
Up to 4 LED outputs with software programmable constant current (3 or 7 mA).
2 General purpose I/Os programmable as interrupts
Up to 8 line inputs programmable as interrupts
Up to 20 outputs
1 line assigned by default as static input after reset
ISO7816-3 UART interface
4 MHz clock generation
Synchronous/Asynchronous protocols (T=0, T=1)
Automatic retry on parity error
Programmable baud rate from 372 clock pulses up to 11.625 clock pulses (D=32/F=372)
Card Insertion/Removal Detection
Smartcard power supply
Selectable card VCC 1.8V, 3V, and 5V
Internal step-up converter for 5V supplied Smartcards (with a current of up to 55mA) using only two external components.
Programmable Smartcard Internal Voltage Regulator (1.8V to 3.0V) with current overload protection and 4 KV ESD protection (Human Body Model) for all Smartcard Interface I/Os
One 8-bit timer
Time Base Unit (TBU) for generating periodic interrupts.
Development tools
Full hardware/software development package
ECOPACK® packages
