MC68HC908BD48 Datasheet, PDF (164/290 Pages) Freescale Semiconductor, Inc – Microcontrollers

Universal Serial Bus Module (USB)
13.3 Features
Features of the USB (universal serial bus) module include the following:
• Integrated 3.3-volt regulator with 3.3-volt output pin
• Integrated USB transceiver supporting low-speed functions
• USB data control logic
– Packet decoding/generation
– CRC (cyclic redundancy check) generation and checking
– NRZI (non-return-to zero inserted) encoding/decoding
– Bit-stuffing
• USB reset support
• Control endpoint 0 and interrupt endpoints 1 and 2
• Two 8-byte transmit buffers
• One 8-byte receive buffer
• Suspend and resume operations
– Remote wakeup support
• USB generated interrupts
– Transaction interrupt driven
– Resume interrupt
– End-of-pack (EOP) interrupt
• STALL, NAK, and ACK handshake generation
13.4 I/O Pins
The USB module uses two I/O pins, shared with standard port I/O pins.
The full name of the USB I/O pins are listed in Table 13-1. The generic
pin name appear in the text that follows.
USB
Generic Pin Names:
D+
D–
Table 13-1. Pin Name Conventions
Full MCU Pin Names:
PTD0/D+
PTD1/D–
Pin Selected for
USB Function By:
USBD+E bit in PDCR ($0049)
USBD–E bit in PDCR ($0049)
Technical Data
164
Universal Serial Bus Module (USB)
MC68HC908BD48 — Rev. 1.0
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