isp1181 NXP Semiconductors, isp1181 Datasheet - Page 9

• Manufacturer Part Number: isp1181
• Description: Isp1181 Full-speed Universal Serial Bus Interface Device
• Manufacturer: NXP Semiconductors

Philips Semiconductors
7. Functional description
9397 750 08938
Product data
7.1 Analog transceiver
7.2 Philips Serial Interface Engine (SIE)
7.3 Memory Management Unit (MMU) and integrated RAM
7.4 SoftConnect
The ISP1181 is a full-speed USB interface device with up to 14 configurable
endpoints. It has a fast general-purpose parallel interface for communication with
many types of microcontrollers or microprocessors. It supports different bus
configurations (see
block diagram is given in
The ISP1181 has 2462 bytes of internal FIFO memory, which is shared among the
enabled USB endpoints. The type and FIFO size of each endpoint can be individually
configured, depending on the required packet size. Isochronous and bulk endpoints
are double-buffered for increased data throughput.
The ISP1181 requires a single supply voltage of 3.3 or 5.0 V and has an internal
3.3 V voltage regulator for powering the analog USB transceiver. It supports
bus-powered operation.
The ISP1181 operates on a 6 MHz oscillator frequency. A programmable clock output
is available up to 48 MHz. During ‘suspend’ state the 115 kHz 10 % LazyClock
frequency can be output.
The transceiver is compliant with the Universal Serial Bus Specification Rev. 1.1 . It
interfaces directly with the USB cable through external termination resistors.
The Philips SIE implements the full USB protocol layer. It is completely hardwired for
speed and needs no firmware intervention. The functions of this block include:
synchronization pattern recognition, parallel/serial conversion, bit (de-)stuffing, CRC
checking/generation, Packet IDentifier (PID) verification/generation, address
recognition, handshake evaluation/generation.
The MMU and the integrated RAM provide the conversion between the USB speed
(12 Mbit/s bursts) and the parallel interface to the microcontroller (max. 12 Mbyte/s).
This allows the microcontroller to read and write USB packets at its own speed.
The connection to the USB is accomplished by bringing D (for high-speed USB
devices) HIGH through a 1.5 k pull-up resistor. In the ISP1181 the 1.5 k pull-up
resistor is integrated on-chip and is not connected to V
is established through a command sent by the external/system microcontroller. This
allows the system microcontroller to complete its initialization sequence before
deciding to establish connection with the USB. Re-initialization of the USB connection
can also be performed without disconnecting the cable.
The ISP1181 will check for USB V
established. V
BUS
Rev. 04 — 30 October 2001
sensing is provided through pin V
Table
Figure
3) and local DMA transfers of up to 16 bytes per cycle. The
1.
BUS
availability before the connection can be
BUS
© Koninklijke Philips Electronics N.V. 2001. All rights reserved.
CC
.
by default. The connection
Full-speed USB interface
ISP1181
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