AT43USB321 Datasheet, PDF (1/4 Pages) ATMEL Corporation – Full-speed USB Hub/Function Microcontroller

Features
• 8-bit AVR^® Core with 83 ns Instruction Cycle Time
• 16K Bytes ROM Program Memory
• 512 Bytes SRAM
• 32 x 8 General Purpose Working Registers
• 20 Programmable I/O Port Pins
• Programmable Serial UART
• SPI Serial Interface
• One 8-bit Timer/Counter with Separate Prescaler
• One 16-bit Timer/Counter with Separate Prescaler
• External and Internal Interrupt Sources
• Programmable Watchdog Timer with On-chip Oscillator
• Bus-or Self-powered USB Hub with Four Downstream Ports
• One Attached Function Port with Three Endpoints
• Programmable 6/12 MHz Oscillator with PLL
• On-chip 3.3V Supply for USB
• 42-pin SDIP and 48-lead TQFP Packages
Overview
The Atmel AT43USB321 is a single-chip microcontroller based USB hub with an
embedded function and a 16K byte masked ROM. The USB hub has five downstream
ports, one of which is permanently attached. Internally the AT43320 consists of a USB
hub and function interface, a hub repeater, and a high-performance, efficient 8-bit
RISC microcontroller. The hub and peripheral device controller function is imple-
mented in the microcontoller’s firmware. To the USB host, the embedded function
appears as an attached port of the hub with its own device address and endpoints.
The AT43USB321 can also be configured as a USB function without the hub.
The USB hardware block consists of a USB transceiver, SIE, hub repeater, endpoint
controllers, and an interface to the microcontroller. The USB hardware interfaces to
the USB host at the transaction level. The CPU of the microcontroller is based on the
Atmel AVR microcontroller. The AVR architecture was developed to be programmed
in C efficiently and with maximum performance.
Full-speed USB
Hub/Function
Microcontroller
AT43USB321
Rev. 1442A–08/99
1