L2800 Conexant Systems, Inc., L2800 Datasheet
L2800
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L2800 Summary of contents
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Introduction The CONEXANT RC56D Modem Device Set supports the USB (Universal Serial Bus), as described by the Universal Serial Bus Specification Revision 1.0. USB provides a flexible interconnect between a PC and a wide range of peripherals, such as to ...
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... Information provided by CONEXANT SYSTEMS, INC. is believed to be accurate and reliable. However, no responsibility is assumed by CONEXANT for its use, nor any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent rights of CONEXANT other than for circuitry embodied in CONEXANT products. CONEXANT reserves the right to change circuitry at any time without notice. This document is subject to change without notice ...
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... VCC SVCC D+ USB D- USB CONTROLLER UNIT (UCU) A0-A15 D0-D7 MODEM DEVICE SET MICRO CONTROLLER UNIT (MCU) [80-PIN PQFP] [100-PIN PQFP] (L2800) 32K x 8 ROM ROM/FLASH ROM Figure 1. Block Diagram XTLI XTLO VD3.3 CLKOUT ~WKRESOUT DPIRQ ~READ ~READ ~WRITE ~WRITE MICRO CONTROLLER A0-A17 ...
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R8292 Signal Pin Assignments and Descriptions The R8292 68-pin PLCC signal pin assignments are shown in Figure 3. The R8292 68-pin PLCC signals are described in Table 2. P0.7 P0.6 P0.5 P0.4 P0.3 P0.2 P0.1 P0.0 VSS VCC P3.0 P3.1/SOF# ...
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Table 2. R8292 68-Pin PLCC Pin Signal Descriptions Signal Name Type ALE O Address Latch Enable. ALE signals the start of an external bus cycle and indicates that valid address information is available on lines A15:8 and AD7:0. An external ...
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Table 2. R8292 68-Pin PLCC Pin Signal Descriptions (Cont’d) Signal Name Type VCC PWR Supply Voltage. Connect this pin to the +5v supply voltage. VSS GND Circuit Ground. Connect this pin to ground. WR# O Write. Write signal output to ...
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USB General Operation Descriptors USB devices report their attributes using descriptors. A descriptor is a data structure with a defined format, which begins with a byte-wide field that contains the total number of bytes in the descriptor followed by a ...
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Offset Field Size bLength bDescriptorType 1 2 bcdUSB 2 bDeviceClass bDeviceSubClass 1 6 bDeviceProtocol 1 bMaxPacketSize0 7 1 idVendor idProduct 2 12 bcdDevice 2 14 iManufacturer 1 iProduct ...
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Configuration Descriptor A configuration descriptor describes information about a specific device configuration (see Table 4). The descriptor describes the number of interfaces provided by the configuration. Offset Field Size 0 bLength 1 bDescriptorType 1 1 wTotalLength bNumInterfaces ...
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Interface Descriptor An interface descriptor describes a specific interface provided by the associated configuration (see Table 5 always returned as part of a configuration descriptor. An interface descriptor never includes endpoint zero in the number of endpoints. Offset ...
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Endpoint Descriptor Each endpoint used for an interface has its own descriptor, which contains the information required by the host to determine the bandwidth requirements of each endpoint (see Table 6). An endpoint descriptor, like an Interface Descriptor, is always ...
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Enumeration The R8292 enumeration process consists of the following steps: 1. Get device descriptor. The host requests and reads the device descriptor to determine maximum packet size. 2. Set address. The host sends the R8292’s function address in a data ...
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Design Considerations In addition to the design considerations found in the RC56D/RC336D Designer’s Guide (Order No. 1154), the following should be taken into account when designing a USB solution. Series Resistor Requirement for Impedance Matching Per USB rev. 1.0 specification, ...
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