Technical Brief O K I A S I C P R O D U C T S W712 Universal Serial Bus Controller 0.5µ m Technology Mega Macrofunction January 1997 ■ ■ ––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– Contents Description................................................................................................................................................................ 1 Features ..................................................................................................................................................................... 1 Signal Descriptions .................................................................................................................................................. 4 Functional Description ............................................................................................................................................ 7 Protocol Engine .................................................................................................................................................. 7 DPLL..................................................................................................................................................................... 7 Timer .................................................................................................................................................................... 7 Status/Control ................................................................................................................................................... 7 FIFO Control ...................................................................................................................................................... 7 Application Interface ......................................................................................................................................... 8 Frame Timer Synthesizer................................................................................................................................... 8 Remote Wakeup.................................................................................................................................................. 8 USB Transfers ..................................................................................................................................................... 8 USB Interface ...................................................................................................................................................... 8 Glossary ..................................................................................................................................................................... 9 Appendix ................................................................................................................................................................. 10 Oki Semiconductor W712 USB Device Controller 0.5µm Technology Mega Macrofunction DESCRIPTION The Universal Serial Bus (USB) Device Controller Mega Macrofunction is a featured element in Oki’s 0.5µm Sea of Gates (SOG) and Customer Structured Array (CSA) families. Oki's USB mega macrofunction provides a USB interface, control/status block, FIFO control, and application interface in two highly integrated submodules for system design interfaces based on the USB protocol. The submodule partitioning allows custom configurations to be easily developed. The USB mega macrofunction connects an industry standard USB interface with a microprocessor-style parallel application interface. This straightforward interface permits easy integration of the USB mega macrofunction to the target application. Using Oki’s USB mega macrofunction, designers can reduce development time, risk, and introduce their USB based products to market faster. Oki’s W712 USB Device Controller mega macrofunction provides a complete USB device interface solution and is fully compliant with the Universal Serial Bus 1.0 specification. For more details on the Universal Serial Bus 1.0 specification, refer to www.usb.org. FEATURES • USB 1.0 compliant • Full-speed (12 Mb/sec) and low-speed (1.5 Mb/sec) support • Microprocessor-style parallel application interface • Supports isochronous, control, interrupt and bulk transfers • Supports four transmit FIFO’s - Three 64 byte - One 2 Kbyte (2-level) • Supports four receive FIFO’s - Three 64 byte - One 2 Kbyte (2-level) • Supports one control endpoint and six additional endpoint addresses • Expandable up to 32 endpoint addresses • Customizable to specific application requirements Supported ASIC Families Family Name Family Type MSM13R0000 Sea of Gates MSM98R000 Customer Structured Array Oki Semiconductor 1 ■ W712 USB Device Controller ■ ––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– Recommended Operating Conditions (VSS = 0 V) Parameter Symbol Min. Typ. Max Unit Power supply voltage VDD 2.7 3.3 3.6 V Operating temperature Tj -40 +25 +85 °C Mega Macrofunction Characteristics Mega Macrofunction W712 Description Logic Gate Count Logic Pin Count USB Device Controller 15797 139 W712 USB Interface Application Interface usb_dpin usb_dmin usb_rxd usb_dpout usb_dmout usb_txenb full_spden sel_ext_pll sys_clock sys_reset testmode mwr_rdb [7:0]ma [7:0]md mrdyb [7:0]pd [3:0]pkt_rdy setup_rdy setup_rdy2 iso_err usb_reset validsof validin validout [7:0]trx_out_data [7:0]rcv_out_data [7:0]trx_in_data [2:0]trx_sel [8:0]trx_wr_ptr [8:0]trx_rd_ptr [6:0]trx_wrb [7:0]rcv_in_data [2:0]rcv_sel [8:0]rcv_wr_ptr [8:0]rcv_rd_ptr [6:0]rcv_wrb osc_clk usb_clk_ext usb_rxd_out Figure 1. Logic Symbol 2 Oki Semiconductor FIFO Interface DPLL Interface –––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– ■ W712 USB Device Controller ■ W712 Z712a Clock W712b DPLL Status/Control Application Interface To Application Module Protocol Engine To USB Transceiver FIFO Control To FIFO’s (data path) To FIFO’s (control) To FIFO’s (data path) Figure 2. W712 Block Diagram ASIC W712 Mega Macrofunction Clock DPLL Status/ Control Optional External DPLL Application Interface Application Module External Module I/O Protocol Engine USB Cable USB Transceiver FIFO Control Data Path FIFO(s)/ Data Mux(s) Data Path Figure 3. Example USB Mega Macrofunction Application Oki Semiconductor 3 ■ W712 USB Device Controller ■ ––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– SIGNAL DESCRIPTIONS USB Interface Signal Type Assertion Description USB Data Plus In. This input and the usb_dmin input are the received single ended data from the USB transceiver. The table below shows values and results for these signals. usb_dpin Input — usb_dmin Input — usb_dpin usb_dmin 0 0 Result SE0 0 1 Logic “0” 1 0 Logic “1” 1 1 Undefined USB Data Minus In. This input and the usb_dpin input are the received single ended data from the USB transceiver. See the table for the usb_dpin description, above, for values and results of these signals. USB Data Plus Out. This output and the usb_dmout signal come from the USB transmit engine and drive the differential output buffers. The table below shows values and results for these signals. usb_dpout Output — 0 Result SE0 0 1 Logic “0” 1 0 Logic “1” 1 1 Undefined — USB Data Minus Out. This output and the usb_dpout signal come from the USB transmit engine and drive the differential output buffers. See the signal description for usb_dpout, above, for a description of signal values and results. Input — USB Differential Received Data. This input comes from the USB differential receiver, and connects to the W712 mega macrofunction. Output LOW USB 3-State Output Enable. This signal connects to the transceiver EB input through an inverter gate. When the W712 mega macrofunction asserts this signal LOW, the transceiver transmits data on the USB bus. See Appendix for the USB transceiver Data Sheets. usb_txenb 4 usb_dmout 0 Output usb_dmout usb_rxd usb_dpout Oki Semiconductor –––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– ■ W712 USB Device Controller ■ Application Interface Signal sys_clock sys_reset Type Assertion Description Input — Clock. Attach a 12-MHz clock signal to this input for full-speed operation and 1.5 MHz for low-speed operation. Input HIGH W712 Reset. Asserting this signal HIGH resets the W712 mega macrofunction. The application module is required to assert this signal at power-on. Input — Write/Read Select. When external application logic asserts this signal HIGH, the application is in WRITE mode. When asserted LOW, the application is in READ mode. External application logic asserts this signal HIGH when writing data to the transmit FIFOs or to the register files. External application logic asserts this signal LOW when reading data from the receiving FIFOs or from the register files. The register files contain information describing the function and transaction status. Output HIGH Input — Address Bus. These eight inputs receive the address of the register files in the USB device controller. Input — Input Data Bus. These eight inputs receive the data to be stored in the register files or transmit FIFOs. Input LOW Data Strobe. When asserted LOW and in WRITE mode, the data on the [7:0]md signal lines are valid for writing. When asserted LOW and in READ mode, the data on the [7:0]pd signals are valid for reading. Output — Output Data Bus. These eight outputs transmit data received from either the register files or the receive FIFOs. Output HIGH Packet Ready. When the W712 asserts this signal, it indicates that one of the four receive FIFOs contains valid data. The application reads the data through the [7:0]pd bus. Input — USB Full Speed Enable. The application module sets this pin to “1” to select full-speed operation and “0” to select low-speed operation. Output HIGH Setup Ready. Asserting this signal HIGH indicates an 8-byte SETUP data has been received from the USB bus. Output HIGH Isochronous Error. Used for loopback testing or to indicate isochronous data has been received with DATA1 PID. Output HIGH Valid SOF. This signal is asserted for two bit times, asynchronous to sys_clock, and indicates a valid SOF token is received when asserted HIGH. Input HIGH Select External PLL. Asserting this signal HIGH selects the external PLL option. Output HIGH Second Setup Ready. Asserting this signal HIGH indicates a new 8-byte SETUP DATA has been received, while internally the device controller still sees the “setup_rdy” signal asserted. This signal will be asserted for two bit times, asynchronous to sys_clock. Input HIGH Testmode. Asserting this signal invokes a loopback test mode. Output HIGH Valid IN. Asserted for two bit times, asynchronous to sys_clock, and indicates a valid IN token is received when asserted HIGH. Output HIGH Valid OUT. Asserted for two bit times, asynchronous to sys_clock, and indicates a valid OUT token is received when asserted HIGH. mwr_rdb usb_reset [7:0]ma [7:0]md mrdyb [7:0]pd [3:0]pkt_rdy full_spden setup_rdy iso_err validsof sel_ext_pll setup_rdy2 testmode validin validout USB Reset. This is the reset signal from the USB device controller. Oki Semiconductor 5 ■ W712 USB Device Controller ■ ––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– FIFO Interface Signal [7:0]trx_out_data [7:0]rcv_out_data Type Assertion Description Input — Transmit FIFO(s} data output. Output data from the transmission RAM selected for reading. Input — Receive FIFO(s) data output. Output data from the receiving RAM selected for reading. [7:0]trx_in_data Output — Transmit FIFO(s) data input. Input data to all transmission RAMs. [2:0]trx_sel Output HIGH [8:0]trx_wr_ptr Output — [8:0]trx_rd_ptr Output — [6:0]trx_wrb Output LOW Transmit FIFO(s) select. Selects one of the seven transmission RAMs for reading. Transmit FIFO(s) write pointer. Write address to all transmission RAMs. Transmit FIFO(s) read pointer. Read address to all transmission RAMs. Transmit FIFO(s) write strobe. Write enable. One bit per transmission RAM. [7:0]rcv_in_data Output — [2:0]rcv_sel Output HIGH Receive FIFO(s) data input. Input data to all receiving RAMs. [8:0]rcv_wr_ptr Output — Receive FIFO(s) write pointer. Write address to all receiving RAMs. [8:0]rcv_rd_ptr Output — Receive FIFO(s) read pointer. Read address to all receiving RAMs. [6:0]rcv_wrb Output LOW Type Assertion Description Input – Oscillator Clock. Attach a 48 MHz clock signal for full-speed operation or a 6 MHz clock signal for low-speed operation. Input – USB Clock External. This is the output clock signal from an external DPLL. This clock should run at 12 MHz for full-speed operation or 1.5 MHz for low-speed operation. If an external DPLL is not used, this pin should be connected to VDD or GND. Output – Synchronized USB Differential Received Data. This signal comes from the USB differential receiver and is synchronized with the oscillator input. This signal connects to the external DPLL if it is used. Receive FIFO(s) select. Selects one of the seven receiving RAMs for reading. Receive FIFO(s) write strobe. Write enable. One bit per receiving RAM. DPLL Interface Signal osc_clk usb_clk_ext usb_rxd_out 6 Oki Semiconductor –––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– ■ W712 USB Device Controller ■ FUNCTIONAL DESCRIPTION The W712 controller consists of two submodules, the Z712a hard macro, and the W712b soft macro, each containing multiple function blocks. The Z712a includes the Protocol Engine, DPLL, and Timer Blocks. The W712b includes the Status/Control, FIFO Control, Application Interface, Frame Timer Synthesizer, and remote wakeup blocks. Protocol Engine The Protocol Engine handles the USB communication protocol. It performs packet sequencing, signal generation/detection, CRC generation/checking, NRZI data encoding, bit-stuffing and packet ID (PID) generation/decoding. DPLL The Digital Phase Locked Loop extracts the clock and data from the USB differential received data. Timer The Timer block monitors idle time on the USB bus. Status/Control The Status/Control block uses transfer type and FIFO state information to manage the reception and transmission of USB data. It monitors the transaction status and communicates control events to the application via the Application Interface. FIFO Control The FIFO control block manages all FIFO operations for transmitting and receiving USB data sets. The W712 supports eight FIFOs (four transmit and four receive). They can be configured as described in the table below. FIFO Configuration FIFO Type Endpoint Address Programmable Function Transmit 0 64 bytes Control Transfers Transmit 5 64 bytes Interrupt and Bulk Transfers Transmit 6 64 bytes Interrupt and Bulk Transfers Transmit 7 2 Kbytes Isochronous, Interrupt, and Bulk Transfers Receive 0 64 bytes Control Transfers Receive 1 64 bytes Bulk Transfers Receive 2 64 bytes Bulk Transfers Receive 3 2 Kbytes Isochronous and Bulk Transfers Endpoints 3 and 7 are 2-level FIFOs which support up to two separate data sets of variable sizes. All FIFOs have flags that detect a full or empty FIFO and have the capability of re-transmitting or re-receiving the current data set. Oki Semiconductor 7 ■ W712 USB Device Controller ■ ––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– Application Interface The Application Interface uses an i486-like bus to interface between the customer’s module and the W712. By using an i486-like bus protocol, the W712 can be easily integrated into any customer-designed module. The integration is limited only by the available gates and I/O pins in the array. The Customer Application Module may have its own external I/O, which do not interface with the W712. All application interface signals are unidirectional, and are either inputs or outputs of the W712. Frame Timer Synthesizer This block synthesizes the SOF signal in the event of a SOF token is lost. Remote Wakeup This block provides support for the remote wakeup function. USB Transfers The W712 supports all four transfer types defined by the USB specification. These are: Control, Isochronous, Interrupt, and Bulk. • Control transfers must be supported by every peripheral for configuration, command and status information flow between the host and peripheral. • Isochronous transfers provide guaranteed bus access and constant data rates for USB devices. • Interrupt transfers support human input devices that need to communicate small amounts of data infrequently. • Bulk transfers enable devices to transfer large amounts of data as bus bandwidth becomes available. USB Interface The W712 connects to the Universal Serial Bus via Oki’s universal USB transceivers. The USB specific I/O converts the W712’s internal unidirectional signals into compliant USB signals. The universal USB transceiver allows the designers’ application module to interface with the physical layer of the Universal Serial Bus. It transmits and receives serial data at both full-speed (12Mb/s) and low-speed (1.5Mb/s) data rates. See Appendix for Oki’s USB transceiver Data Sheets. 8 Oki Semiconductor –––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– ■ W712 USB Device Controller ■ GLOSSARY Explanation Term Bandwidth The amount of data transmitted per unit of time, typically bits per second (bps) or bytes per second (Bps). Bit A unit of information used by digital computers. Represents the smallest piece of addressable memory within a computer. A bit expresses the choice between two possibilities and is typically represented by a logical one (1) or zero (0). Bit Stuffing Insertion of a “0” bit into a data stream to cause an electrical transition on the data wires allowing a PLL to remain locked. Bulk Transfer Nonperiodic, large burst communication typically used for a transfer that can use any available bandwidth and also be delayed until bandwidth is available. Control Transfer One of four Universal Serial Bus Transfer Types. Control transfers support configuration/command/status type communications between client and function. CRC See Cyclic Redundancy Check. Cyclic Redundancy Check A check performed on data to see if an error has occurred in transmitting, reading, or writing the data. The result of a CRC is typically stored or transmitted with the checked data. The stored or transmitted result is compared to a CRC calculated for the data to determine if an error has occurred. Device Endpoint A uniquely identifiable portion of a Universal Serial Bus device that is the source or sink of information in a communication flow between the host and device. Endpoint See Device Endpoint. Interrupt Transfer One of four Universal Serial Bus Transfer Types. Interrupt transfers characteristics are small data, non-periodic, low frequency, bounded latency, device initiated communication typically used to notify the host of device service needs. Isochronous Transfer One of four Universal Serial Bus Transfer Types. Isochronous transfers are used when working with isochronous data. Isochronous transfers provide periodic, continuous communication between host and device. Non-Return-to-Zero-Invert A method of encoding serial data in which ones and zeroes are represented by opposite and alternating high and low voltages where there is no return to zero (reference) voltage between encoded bits. Eliminates the need for clock pulses. NRZI See Non-Return-to-Zero-Invert. PLL Phase Locked Loop. A circuit that acts as a phase detector to keep an oscillator in phase with an incoming frequency. Protocol A specific set of rules, procedures, or conventions relating to format and timing of data transmission between two devices. Transaction The delivery of service to an endpoint. Consists of a token packet, optional data packet, and optional handshake packet. Specific packets are allowed/required based on the transaction type. Transfer One or more bus transactions to move information between a software client and its function. Transfer Type Determines the characteristics of the data flow between a software client and its function. Four Transfer types are defined: control, interrupt, bulk, and isochronous. Universal Serial Bus A collection of Universal Serial Bus devices and the software and hardware that allow them to connect the capabilities provided by functions to the host. Universal Serial Bus Interface The hardware interface between the Universal Serial Bus cable and a Universal Serial Bus device. This includes the protocol engine required for all Universal Serial Bus devices to be able to receive and send packets. USB See Universal Serial Bus. Oki Semiconductor 9 ■ W712 USB Device Controller ■ ––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– 10 Oki Semiconductor –––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– ■ W712 USB Device Controller ■ APPENDIX 0.5µm MSM13R0000 SOG and MSM98R000 CSA USB I/O Library Data Sheets The following section contains USB I/O library data sheets Oki Semiconductor 11 ■ W712 USB Device Controller ■ ––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– 12 Oki Semiconductor 0.5µm Sea of Gates-MSM13R0000 BUD2SLL MSM13R-Rel. 1.0 Cell Count USB I/O Buffer with Full / Low Speed 4 I/O 2 PADs Logic symbol I A Y YB O I AN YD YBN O EB I S YN GN Truth Table Pin Definition Fan-in Fan-out (MAX.) Name Type A In 2.9 - AN In 2.9 - EB In 3.0 - GN In 7.3 - S In 5.8 - YB I/O - - YBN I/O - - YD Out - 43 Y Out - 40 YN Out - 40 Input S EB A AN GN YB YBN YB YBN YD Y YN 0 1 0 1 X X X 1 0 0 1 X X X 1 1 1 1 0 0 X 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 Z 1 0 Z 0 1 0 1 - 1 0 0 1 - 0 1 X X 0 1 1 0 1 0 1 0 1 X 1 0 0 1 1 0 X 0 1 0 1 X X 0 1 0 1 X 1 0 0 1 X X 1 0 0 1 X 1 1 1 1 0 0 1 1 1 1 0 1 0 0 0 0 0 0 1 1 1 1 1 0 1 Z 1 0 Z 0 1 0 1 0 1 0 1 1 0 0 1 1 0 0 1 - - 0 1 X X 0 1 1 1 1 1 1 0 1 0 1 0 1 0 1 0 1 X 1 0 0 1 1 0 1 0 0 1 X 1 1 1 1 1 1 1 1 1 1 Note: S=0: Low Speed Function S=1: Full Speed Function BUD2SLL Oki Semiconductor Output 0.5µm Sea of Gates-MSM13R0000 MSM13R-Rel. 1.0 USB I/O Buffer with Full / Low Speed BUD2SLL Delay Parameters (VDD = 3.3V,Tj=25°C) To LH/HL tpd0' (ns) α (ns/FO) γ (ns/pF) YB YD YBN YD GN YD YB Y YBN YN LH HL LH HL LH HL LH HL LH HL 1.658 1.593 1.658 1.593 0.668 1.230 0.480 1.033 0.480 1.033 0.021 0.016 0.021 0.016 0.021 0.016 0.022 0.032 0.022 0.032 0.582 0.384 0.582 0.384 0.582 0.378 0.591 0.767 0.591 0.767 tpd0' (ns) α (ns/FO) - γ (ns/pF) S=0: Low Speed To LH/HL A YB AN YBN EB YB EB YBN GN YB GN YBN LH HL LH HL LZ ZL HZ ZH LZ ZL HZ ZH LZ ZL HZ ZH LZ ZL HZ ZH 113.448 112.385 121.419 112.658 1.992 2.567 1.496 70.919 2.516 2.798 2.562 67.373 1.853 2.127 1.335 93.127 2.401 2.367 2.401 89.655 4 I/O 2 PADs S=1: Full Speed From From Cell Count 0.082 0.071 0.082 0.071 0.190 0.071 0.215 0.082 0.190 0.071 0.215 0.082 0.190 0.071 0.215 0.082 0.190 0.071 0.215 0.082 α γ (ns/FO) (ns/pF) A LH YB 4.550 0.608 HL 4.261 0.238 AN 4.569 0.498 LH YBN 4.246 0.237 HL EB YB LZ 1.191 0.152 ZL 4.774 0.149 HZ 3.193 0.165 ZH 1.221 0.068 EB YBN LZ 1.194 0.366 ZL 4.773 0.145 HZ 3.703 0.407 ZH 0.692 0.098 Power Dissipation (VDD = 3.3V,Tj =25°C) S=0:Low Speed Function AC: 2940.4µW/MHz DC: 311.2µW YB=VIH=3.3V, YBN=VIL=0V 1730.9µW(#2) YB=VOH≥2.8V, YBN=VOL≤0.3V 1353.8µW(#2) YB=VOL≤0.3V, YBN=VOH≥2.8V 0.0µW when Power Down Mode(GN=1) is used S=1:Full Speed Function AC: 48.0µW/MHz DC: 311.2µW YB=VIH=3.3V, YBN=VIL=0V 1009.4µW(#1) YB=VOH≥2.8V, YBN=VOL≤0.3V 723.4µW(#1) YB=VOL≤0.3V, YBN=VOH≥2.8V 0.0µW when Power Down Mode(GN=1) is used From To LH/HL tpd0' (ns) Output Switching Parameters (VDD = 3.3V,Tj =25°C) DC Parameters (VDD: core/IO = 3.3/3.3V±0.3V,Tj = 0 to 85°C) Parameter VDI Vt+ VtVOH VOL Value 0.2V 2.0V 0.8V 2.8V 0.3V Conditions 15kΩ to GND 1.5kΩ to 3.6V Note: VDI = Differential Input Sensitivity BUD2SLL Oki Semiconductor Output #1 YB YBN #1 #2 YB YBN #2 tr0 (ns) γr (ns/pF) tf0 (ns) γf (ns/pF) 1.822 0.095 2.041 0.090 1.491 0.105 1.821 0.087 79.749 0.106 77.070 0.055 136.166 0.001 78.704 0.085 Note: #1 = Full Speed Function YB: RPD=15kΩ , RPU=1.5kΩ YBN: RPD=15kΩ #2 = Low Speed Function YB: RPD=15kΩ YBN: RPD=15kΩ , RPU=1.5kΩ References See the USB Specification Revision 1.0 for more information on USB functionality. The information contained herein can change without notice owing to product and/or technical improvements. Please make sure before using the product that the information you are referring to is up-to-date. The outline of action and examples of application circuits described herein have been chosen as an explanation of the standard action and performance of the product. When you actually plan to use the product, please ensure that the outside conditions are reflected in the actual circuit and assembly designs. OKI assumes no responsibility or liability whatsoever for any failure or unusual or unexpected operation resulting from misuse, neglect, improper installation, repair, alteration or accident, improper handling, or unusual physical or electrical stress including, but not limited to, exposure to parameters outside the specified maximum ratings or operation outside the specified operating range. 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