Lucent Technologies USS-720 manual Filter Bypass Mode, High Drive Mode, Self-Powered Mode

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Preliminary Data Sheet, Rev. 5	USS-720	Instant USB
September 1999	USB-to-IEEE	1284 Bridge

Filter Bypass Mode

For embedded applications, the USS-720 IEEE 1284 port can be operated in Filter Bypass Mode. This mode disables digital ﬁltering of the parallel port signals into the USS-720, providing a performance improvement.

Note: Since digital ﬁltering is disabled, the parallel port lines will be susceptible to noise. Do not use this mode when driving across a cable.

Filter Bypass Mode is enabled by connecting a 20 kΩ pull-down resistor to the SUSPEND line.

High Drive Mode

If desired (e.g., for embedded applications), the USS- 720 IEEE 1284 port can operate in High Drive Mode. In

this mode, all parallel port signals are constantly driven by 14 mA totem-pole drivers, rather than with the normal open-drain drivers. This eliminates the need for external pull-up resistors on the parallel port signals (and, if driving another chip on the same board, there is no need for the 24 Ω impedance matching resistors). High Drive Mode is enabled by connecting a 20 kΩ pull-down resistor to the SK line.

Self-Powered Mode

When using the USS-720 in a self-powered applica- tion, attach a 5 kΩ pull-up resistor to the CS line. This causes the correct self-powered status to be reported in response to a USB Get-Status command.

Absolute Maximum Ratings

Stresses in excess of the absolute maximum ratings can cause permanent damage to the device. These are abso- lute stress ratings only. Functional operation of the device is not implied at these or any other conditions in excess of those given in the operations sections of this data sheet. Exposure to absolute maximum ratings for extended periods can adversely affect device reliability.

Table 30. Absolute Maximum Ratings

Parameter	Symbol	Min	Max	Unit

Ambient Operating Temperature Range	TA	0	70	°C

Storage Temperature	Tstg	−40	125	°C

Voltage on Any Pin with Respect to Ground	VIN	VSS − 0.3	VDD + 0.3*	V

*Except for 5 V tolerant buffers where VIN max = VDD5 max + 0.3 V. VIN must never exceed VDD5 + 0.3 V at any time. VDD5 should be selected to satisfy this condition.

Lucent Technologies Inc.

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Contents Information Manual, Rev September IntroductionTable of Contents September USB-to-IEEE Bridge Information Manual, Rev Evaluation Kit for USS-720USS-720 USB Device Driver Preliminary User Guide IOCTL1284 TerminateIOCTLSET1284REGISTER USS-720 USB Port Monitor Application Note Evaluation Kit Contents \SAMPLES Hardware RequirementsGetting Started Instructions OSR2.1 Cable Installation InstructionsWindows 98 Cable Installation Instructions Software UpdatesUSB Driver and Port Monitor Plug and PlayPort Creation Eeprom Lucent Technologies Inc In-System Design, Inc Lucent Technologies Microelectronics GroupUSB Applications Support September Introduction Evaluation Kit SoftwareUSS-720 Driver Software Object Code License Agreement FebruaryOwnership USS-720 Software Use Agreement FebruaryLicensed Software Furnishing of Licensed SoftwareFebruary Software Use Agreement USS-72004 Conﬁdentiality Warranty and IndemnityAgreement Prevails Nothing ConstruedIntegration PublicityNonassignability AddressesDisputes Applicable LawUSS720.SYS USS720.INFDocumentation USS-720 Software Use Agreement February Application Note, Rev February Software ComponentsCustomer-Deﬁned Data Plug and Play Operation PnPPrinter Enumeration USB Hardware Types Supported Power ManagementInstallation Process Operating Systems SupportedPrint Types Supported Printer Types SupportedFeatures Preliminary Data Sheet, Rev SeptemberDescription Table of Contents Preliminary Data Sheet, Rev USS-720 Pin InformationUSB-to-IEEE Parallel Port nAck Signal Active-Low Parallel Port nAutoFd Signal Active-LowParallel Port nSelectIn Signal Active-Low Parallel Port nInit Signal Active-LowDescriptor Locations OverviewUSB Port Device Descriptor, Conﬁgurations, and Inter- facesUSB-to- Ieee 1284 Bridge September Onboard Device DescriptorDevice Descriptor Offset Field Size Value Description Conﬁguration Descriptor USB-to- IeeeBulk Out Endpoint Descriptor, I0A0E1 Interface DescriptorsSeptember USB-to-IEEE1284 Bridge Bulk Out Endpoint Descriptor, I0A1E1Bulk In Endpoint Descriptor, I0A1E2 Bulk Out Endpoint Descriptor, I0A2E1 Bulk In Endpoint Descriptor, I0A2E2Interrupt Endpoint Descriptor, I0A2E3 Pipes RequestsStandard Requests Get Port Status Data Bit Description Printer Class-Speciﬁc RequestsVendor-Speciﬁc Requests GET1284REGISTERSET1284REGISTER Register-Based Operation Ieee 1284 PortByte Register Data RegistersGET1284REGISTER Data Byte Register Data Interrupt Pipe Read DataStatus Register Address Bit Symbol Default Bit Symbol Bit DescriptionParallel Port nFault Signal Reserved USB-to-IEEE1284 Bridge Control Register Address Bit SymbolAccess Default Bit Symbol Bit Description Parallel Port nInit SignalUSS-720Instant USB ECP Command Register Address Bit Symbol Access Mode20 Description Extended Control Register Address Bit SymbolUSS-720 Control Register Address Bit Symbol USS-720 Setup Register Address Bit Symbol Interrupts External Crystal Connection External Circuitry RequirementsAbsolute Maximum Ratings Parameter Symbol Min Unit Filter Bypass ModeHigh Drive Mode Self-Powered ModeClklo Clkhi Electrical CharacteristicsParameter Symbol Test Conditions Min Typ Max Unit Capacitance Values Parameter UnitTiming Characteristics Setup and Hold Input Timing ParameterOutput Delay Timing Parameter Min Max Unit Device Code Package Comcode Outline DiagramOrdering Information Pin MqfpApplication Note February Description USS ParallelPort Bridging USB to Typical Circuit ShowingLucent Technologies Inc Preliminary User Guide, Rev February Signal DirectionsIOCTL1284 Setmode USB Device Driver InitializationO File Functions Preliminary User Guide, Rev USS-720 FebruaryCreateFile ReadFile Error CodesWriteFile DeviceIoControl CloseHandle Control Code Description O Control CodesParameters IOCTL1284 EcpfwdtorevIOCTL1284ECPREVTOFWD IOCTL1284 Ecpsetchannel IOCTL1284 Setmode Register Mode DescriptionIOCTL1284 Terminate Bulkinpipe IoctlabortpipeValue Description BulkoutpipeIoctlcancelpiperequest IOCTLGET1284REGISTER ALTINTERFACE2 IoctlgetaltsettingALTINTERFACE0 ALTINTERFACE1Ioctlgetcapabilities Ioctlgetconfigurationdescriptor Ioctlgetdevicedescriptor Ioctlgetdeviceinstances Ioctlgetinterface Bit Meaning IoctlgetportstatusCommand Description IOCTLISSUEUSS720COMMANDByte Description IoctlreadinterruptpipeIoctlresetpipe IOCTLSET1284REGISTER Ioctlsetaltsetting Ioctlsoftreset Data Structure O Control Data StructuresDeviceinstanceheader DeviceinstanceREGISTER1284, *PREGISTER1284 REGISTER1284ADVREGISTER1284, *PADVREGISTER1284 ADVREGISTER1284Lucent Technologies Inc USS-720 USB Port Monitor Printer Cable with Instant USB USS-720 Application Note USB Port Monitor FebruaryClick on Enter Library Software Installation InstructionsW98USS720EvalKit2402.zip to download the installation ﬁles Application Note JuneSeptember MN99-052CMPR-1 Replaces MN97-061CMPR-04