SBPH400-3 IEEE1394 3-Port 400Mbps Physical Layer PRELIMINARY DATA ■ ■ FEATURES ■ 3 ports fully compliant with IEEE 1394-1995 cable environment specification ■ Fully implements IEEE P1394a D2.0 proposal ■ S100, S200 and S400 speeds ■ IEEE P1394a proposal PHY-LINK interface ■ IEEE P1394a proposal Suspend/Resume ■ OHCI support ■ Per port disable ■ Automatic power saving ■ Optional isolation support ■ IEEE P1394a proposal arbitration enhancements ■ IEEE P1394a proposal register set and remote register read ■ Advanced Data-Strobe clock and data recovery ■ Digital delay-lock loop technology - no filtering capacitors ■ Built-in self-test (BIST) of analog and digital port logic ■ JTAG Test Access Port ■ 3.3V supply ■ 80 pin plastic TQFP package APPLICATIONS ■ Host processor interface ■ Host processor adapter cards ■ Digital set-top box ■ Digital Video Recorder/ Player ■ Repeaters 16 March 1998 The information in this datasheet is subject to change P1394a Link interface Link layer interface logic Reset and arbitration Port logic 1394 cable interface @400 Mbps Built-in self test Port logic Port logic 1394 cable 1394 cable interface interface @400 Mbps @400 Mbps 42 1697 05 Table of Contents 1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2.1 Transmitter and receiver port interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2.2 Connect detect and bias . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 2.3 Configuration pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 2.4 Suspend/Resume/Disable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2.5 Data encoder/decoder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2.6 Bus reset, arbitration and control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 2.7 PHY packets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 2.8 2.7.1 Link device interaction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 2.7.2 Self-ID packet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 2.7.3 Link_on packet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 2.7.4 PHY configuration packet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 2.7.5 Ping packet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 2.7.6 Remote Access and Reply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 2.7.7 Remote Command and Confirmation packets . . . . . . . . . . . . . . . . . . . . . . 14 Link interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 2.8.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 2.8.2 Types of operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 2.8.3 Control pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 2.8.4 Link device request (LREQ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 2.8.5 Bus request . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 2.8.6 Register Read/Write requests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 2.8.7 Status transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 2.8.8 Transmit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 2.8.9 Receive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 2.8.10 SBPH400 registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 2.9 Reset and initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 2.9.1 Power on . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 2.9.2 PHY/Link Interface start-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 2.9.3 PHY/Link interface reset and disable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 2.9.4 LKON (link on) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 2.10 ISO (isolation) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 2.11 CPS (cable power status) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3. . . . . 32 3 Pin Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 2/43 1 Table of Contents 4 Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 4.1 Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 4.2 Operating conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 4.3 DC characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 5 AC characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 6 Package Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 7 Application Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 3/43 SBPH400-3 1 Overview The S B P H 4 0 0-3 provides the analog transceiver functions needed to implement a 3 port node in an IEEE 1394-1995 cable network. There are 2 differential line transceivers in each cable port. The following main functions are included in the chip: • Detection of connection status using line condition detection circuitry. • Node initialization and bus arbitration. • Reception and Transmission of Data Strobe Bit Level encoded packets • Interface to higher level protocol devices (Link layer). • Production test through JTAG The interface to the Link conforms to the IEEE 1394-1995 Annex J with 2 control lines and an 8 bit data bus, as modified by the P1394a proposals. The basic chip timing may be controlled either from a 24.596 MHz crystal controlling an internal oscillator or from an external 24.596 MHz oscillator. The internal delay lock loop (DLL) generates the various internal clocks for the high speed serial data transmission and reception. Note that there is no need to provide filtering capacitors. The input clock is used to derive the 49.152 MHz clock for the interface to a Link layer device, which provides the data to be transmitted on the 8 bit Link data interface. The data from the Link layer device is latched internally in the chip at 49.152 MHz. The bits are serialized and encoded in the Data Strobe Bit Level Encoding format. The Data information is transmitted differentially on the TPB cable pair(s) while the Strobe information is transmitted differentially on the TPA cable pair(s). Data can be transmitted at 98.304 Mbit/s (S100 speed), 196.608 Mbit/s (S200 speed) or 393.216 Mbit/sec (S400 speed). When a packet is received by a port, the corresponding transmitters are disabled and the receivers enabled. The received encoded Data information from TPA cable pair and the encoded Strobe information from the TPB cable pair are decoded to extract the receive clock signal and the data bits. The data bits are converted into a parallel format and transmitted to the Link Layer controller and the other active cable ports after resynchronisation to the system clock. Figure 1.1 is a block diagram of the SBPH400-3. The portion of circuit which is circled by the dash line is termed the Cable Media Interface . All signals between the Digital Circuit and the Cable Media Interface are pure digital signals. The signals which are driven on and received from the cable are analog differential and common mode signals. The differential signals on the cable transmit data or arbitration states, while common mode signals indicate the cable connection status or transmission rate (speed). 4/43 2 SBPH400-3 Figure 1.1 SBPH400-3 block diagram Cable Media Interface D[0:7] Data Encoder/ Decoder Ctl[0:1] LReq SClk CPS LINK Interface I/O Strb_Tx Data_Tx Data_Rx Speed_Tx Strb_En Data_En Arb_A_Rx Arb_B_Rx LPS ISO CMC LKON Speed_Rx ... RESET# LACT Transmitter & Receiver ... ... PDISABLE TPB1 TPB1# Port 2 Arbitration and Control State Machine Logic TPA1# Port 1 (Driver/Receiver, Arb. Comparator, Port_Status, Speed Monitor) Port_Status ... PC[0:2] TPA1 Strb_Rx (same as Port 1) Port 3 (same as Port 1) TPA2 TPA2# TPB2 TPB2# TPA3 TPA3# TPB3 TPB3# QX1 CLK24/QX0 TCK TRST# TMS TDI TDO TEST ACCESS Bias JTAG TPBias1 TPBias2 TPBias3 R0 PORT R1 TESTMODE TESTENABLE SCI[2:0] BUILT-IN SELF TEST SCO[2:0] 5/43 2 SBPH400-3 2 Functional Description 2.1 Transmitter and receiver port interface Figure 2.1 Analog port schematic Twisted Pair A Ph ys ical con ne c tio n de te ction c o m pa rato r Twisted Pair B I CD Con Tp Bia s d isa ble + C o m m o n m o d e sp ee d s ig na l c u rren t T pB ia s ’ - S20 0 Spe e d_T x 0. 3 µf m in VG S4 00 Sp ee d_T x TPB TPA D rive r 55 Ω Strb_ Tx 55 Ω 5 5Ω Da ta _T x TPA* R ec eiv er Da ta_Rx 5 5Ω TPB * 5 kΩ ±5% 25 0 pF Da ta _Enab le Strb_ Ena ble Strb _ Rx + - + - VG Arb_A_Rx - - A rbitr ation Co m pa ra to rs A rb itra tion C om p arator s + - - 7 kΩ 7 kΩ Bia s + S40 0 Spe ed_ Rx Arb _ B_Rx + 7 kΩ S20 0 Spe ed _Rx (sh ared with TPA a nd othe r p orts) + + S 20 0 _ref 7kΩ + - 0.8V T pB ia s de te c tion c o m pa rato r + - S4 00 _r ef The SBPH400-3 implements three cable interface transceiver ports. Each port operates independently from the other ports, under control of the device control logic. Each port provides two pairs of signals, denoted TPA, TPA#, and TPB, TPB#. Each signal is implemented using a driver and a receiver connected to a single pin (total of four pins per port). In various modes, the driver and receiver are enabled, either separately or both at the same time (for bi-directional signalling). 6/43 2 SBPH400-3 A port may be disconnected, disabled, suspended or active. When active, each port operates in the following modes: Idle mode: In this mode, each port’s driver is disabled, i.e. the port presents a high impedance on all four signals. The inputs are continuously sampled, and if a signal is detected (which will normally indicate an arbitration signal from a connected port) then this is passed to the arbitration logic. Arbitration mode: In this mode, both pairs engage in bi-directional untimed digital signalling. Each pair transmits (under the control of the arbitration logic) either a logic 1 using differential signalling, a logic 0 using differential signalling, or high impedance Z. Simultaneously, the signal on each pair is continuously sampled, and is interpreted as a logic 1, logic 0 or high impedance Z. The sampled signal is a combination of the transmitted signal and the signal being transmitted on the corresponding pair by a connected transceiver (NB the cable implements a “twist” - TPA is connected to the far end TPB, and vice versa). The signal is interpreted using the 1394 1’s dominant rule and passed to the arbitration logic for interpretation by the arbitration state machine. If a 11 level is received then this is interpreted as a reset signal and passed to the control logic. Speed signalling mode: Speed signalling uses common mode signalling. It is used to signal the transmission speed capabilities of the device (during the Self_ID phase of bus initialization) and in parallel with the transmission of Data_Prefix arbitration signal during arbitration to indicate the speed of the packet about to be transmitted. To send a speed signal, the port generates a common mode current signal on TPB and TPB# for 100 ns. This signal results in a drop of the current mode bias voltage through a pair of 55 Ohm resistors connected between the TpBias output and the TPA, TPA# pair at the receiving end. To receive a speed signal, the port determines the speed by measuring the amount of voltage drop on the TPA pair, compared to the TpBias signal it is generating. The port samples the speed signal at 20ns intervals in order to provide filtering against intermediate values or against noise. The SBPH400 requires two consecutive samples of a S200 or a S400 signal (as appropriate) in order to identify a valid speed signal. If no speed signal is identified when data transmission starts, then the data is assumed to be transmitted at S100 speed. Data transmission mode: In this mode, which always follows arbitration mode, the port transmits the data and strobe signals received from the data encoder on the TPB pair and the TPA pair respectively. The transmission uses uni-directional differential data signalling on each pair. Note that at the end of arbitration mode, the port will be transmitting an untimed signal of 01. If the first bit to be transmitted is a zero, then this will cause a transition on “data” (i.e. TPB, so that TPA, TPB transmit 00), if the first bit to be transmitted is a 1, then this will cause a transition on “strobe” (i.e. TPA, so that TPA, TPB transmit 11). The receivers are disabled during data transmission. At the end of data transmission mode, the port reverts to idle mode. Data reception mode: This mode always follows arbitration mode. The port presents high impedance on its output drivers (and ignores the data which is being repeated to the other ports by the data encoder/decoder). The port implements a differential receiver for each of TPA (data) and TPB (strobe) pairs, and passes the received binary signals to the data 7/43 2 SBPH400-3 decoder. Advanced logic is used to ensure reception of the Data and Strobe signals at speeds of up to 400 MHz. 2.2 Connect detect and bias A low current connect detect circuit is used to detect a physical connection. A current, applied to the TPA pair and sensed via a local Schmitt trigger, will indicate a disconnected state unless there is a physical connection to ground via the 5K resistor connected to the TPB pair at the far end. Note that this does not require the far end to be powered. This mechanism operates only when the port is not generating TpBias. In order to implement the cable detection, suspend/resume and speed signalling functions, a common mode bias voltage has to be provided to the TPA pair. A separate TpBias pin is provided for each port, which should be connected to the TPA pair via a pair of 55 Ohm resistors, as shown in Figure 2.1. The use of a separate pin for each port avoids problems of possible interference between the common mode signalling on each port, or possible misdetection of a disconnect. A single external resistor should be provided between pins R0 and R1 in order to set the internal operating and the cable driver output currents. A low TCR 3KΩ ±1% resistor should be used. 2.3 Configuration pins The SBPH400 provides six configuration pins which may be hard wired high or low, or may be directly controlled from a link layer device. Four of the pins are used to initialize registers which control configuration status bits in the self identification packet. The PC[0:2] pins provide the power reset value for the power class register, which is reported in the Self_ID packet in the pwr field. The CMC pin provides the power reset value for the C register, with is reported in the Self_ID packet in the C field to indicate if the node is a contender for the bus or isochronous resource manager. The LACT pin is used to initialize the value of the Link_active register on power reset. If set to zero, this allows the node to appear as having an inactive link (the L field in the Self-ID packet will be zero) until application software sets the Link_active bit to 1. The PDISABLE pin is used to initialize all ports as disabled on power reset. This satisfies the OHCI requirement, and allows software to be initialized before the device starts to participate on power-on as a new device on the bus. The ISO pin is used on power reset to determine the operating mode of the PHY/Link interface (DC coupled or using a DC isolation barrier). The SBPH400 also has a number of pins which are intended for use during production test only, and are held to ground or V DD as appropriate in normal operation. 8/43 2 SBPH400-3 2.4 Suspend/Resume/Disable Each port independently implements the P1394a suspend/resume proposal. At any one time, a port may be disconnected, disabled, suspended or active. On power reset, if PDISABLE = 0 then all ports are initialized as disconnected, and then, if any ports are physically connected, the normal new connection actions taken. If PDISABLE = 1 then all ports are initialized as disabled. When a port is not active, the TpBias output for the port is disabled, all outputs of the port are set to high impedance and any incoming arbitration signals on TPA and TPB are ignored. A port may be disabled or re-enabled by a command (register write) from the local link, or by remote PHY command packet. While disabled, the port ignores any incoming TpBias signal but the port continues to monitor its connection status using the connect_detect mechanism. A change in connection status will cause an interrupt to the link or a LinkOn packet as appropriate and according to the controlling flags. When re-enabled and connected, the port is treated as suspended (see below). When disconnected, a port ignores any incoming TpBias signal but continuously monitors the connection status using the connect detect circuitry. On connection, the port attempts to become active, but if an incoming TpBias is not then detected, then the port is suspended with the fault bit set. While active, the port continuously senses the common-mode bias input voltage on the TPB pair. The presence of a bias voltage on the TPB pair indicates that the port is connected to an active port on some other device. Similarly, the absence of a bias voltage indicates the lack of such a connection or that the far end port has been powered off. On detection of loss of bias, the port is treated as suspended (see below) A port may be suspended by a remote PHY command packet. In this case, it engages in a protocol with the remote connected port, resulting in that port too being suspended. It may be suspended on loss of incoming TpBias on an active port. A port may also be suspended as a result of its active connected port being suspended. A connected disabled port is treated as suspended when re-enabled. While suspended, the port monitors both TpBias and its connection state using the connect_detect mechanism. If a disconnection is detected, then the port becomes disconnected. If a TpBias signal is detected, then the port resumes to its active state. A port may be instructed to resume by means of a remote command packet, in which case it generates a TpBias signal. This will indicate to the connected peer port that it too should resume. It should be noted that any change of port state to or from the active state has the effect of a topology change, and that reconfiguration of the bus is necessary. To ensure that this occurs, the SBPH400 initiates the appropriate bus resets as defined in the P1394a proposal. When a port becomes disconnected, disabled or suspended, it carries out the appropriate actions and then automatically enters a low power mode. Normal operation (on full power) is restored after an appropriate delay (to allow the internal clocks to stabilize) on any change in 9/43 2 SBPH400-3 port state. If all ports are in a low power state, and the PHY/Link interface is disabled, then the SBPH400 implements the necessary delays to allow the SBPH400 core to enter a low power state in future versions with no functional or timing change. 2.5 Data encoder/decoder The data encoder/decoder implements the SGS-Thomson patented “Data/Strobe” clock encoding technique, as described in the 1394 specification. Data to be transmitted is serialized and encoded into the appropriate Data and Strobe signals. These are send simultaneously to all active ports for outputting. All output is clocked by the SBPH400 clock derived from the local crystal. Note that data to be transmitted may be received from an incoming port, or from the link interface. Data received from a port (only at most one port can be receiving data at any one time) is resynchronized to the local clock using a small elastic buffer, as the clock frequency of the incoming data may differ (by up to 200 ppm) from the local clock. The buffer is sized to avoid underflow or overflow for the longest possible packet.The data is repeated to the ports and to the link layer as described above, using the local reference clock. 2.6 Bus reset, arbitration and control The SBPH400 enters bus reset on power reset, if the reset signal is sensed on any connected port’s arbitration signal lines, on a request from a link layer device, on resume from suspend or on connection of detection on any port (possibly after a delay, to allow for an incoming reset), on loss of TpBias on an active parent port, on entry to suspend as a result of the peer port being suspended or disabled, or if the device stays in any state other than Idle, Tree-ID start, Transmit or Receive for longer than 300 µsec. In some circumstances, the device will arbitrate for the bus before generating a reset signal, as defined in the P1394a proposal. This results in minimum disruption to high priority traffic. On entry to reset, the arbitration control logic enters a Tree-ID phase. Either the node will be identified an isolated node, or the node will be identified as the root, and all active ports will be identified as child ports, or one active port will be the port to the node’s parent, and the other active ports will be identified as child ports. The control logic will then engage in Self-ID, in which all nodes are allocated a node-ID and exchange self-ID packets (see 2.7.2). All received self-ID packets are passed to the link layer device. Speed capabilities are exchanged during the Self-ID process with all connected active nodes. In normal operation, the control logic implements the functions of the root, should the result of the Tree-ID process be that this node becomes the root. The control logic accepts arbitration requests from either the local link or any port. Upon receipt of an arbitration request, the request is accepted locally (if the node is the root) or repeated towards the root node via the parent port. Data Prefix (01) is transmitted on all other ports, which indicates that any arbitration request from these ports is rejected. 10/43 2 SBPH400-3 If the request for transmit comes from the local link, then the arbitration control logic waits for an appropriate gap (all interfaces Idle), and then (unless the request is an immediate request) arbitrates as above. The arbitration logic supports all the arbitration enhancements specified in IEEE P1394a:• arbitrated reset (a short reset which is delayed until a subaction gap arbitration) • ack-accelerated arbitration (immediate arbitration after an ACK) • fly-by arbitration (concatenation of packets after a packet received from a child port) 2.7 PHY packets 2.7.1 Link device interaction The SBPH400 will forward to the link (if the PHY/Link interface is active) every PHY packet received on the bus. The SBPH400 will interpret every PHY packet which it receives from the local link device for transmission on the bus (in addition to responding to every PHY packet received from the bus). The SBPH400 will act on it in exactly the same way as if the packet was received from the bus. 2.7.2 Self-ID packet The Self-ID packet has the following format: Figure 2.2 1 0 Self-ID packet format phy_ID 0 L gap_cnt sp rsv c pwr p0 p1 p2 i 0 logical inverse of first quadlet 11/43 2 SBPH400-3 The fields in the Self-ID packet are derived as shown in Table 2.1. Table 2.1 Self ID packet fields Field phy_ID Derived from Comment L self-ID process or set_PHY_ID packet Link enabled register physical node identifier Logical AND of LPS signal and the Link_active register gap_cnt sp Gap_Count register Max_Phy_Speed current value of Gap Count register 10b (S100, S200 and S400 capable) rsv (reserved) 00b c Contender register current value of C register pwr p0, p1 p2 Power class register port status for port 0, 1 and 2 respectively current value of Power class register 01 - not active (disabled, disconnected or suspended) 10 - active and connected to parent node 11 - active and connected to child node i initiated reset set whenever the node initiated the current bus reset 2.7.3 Link_on packet The SBPH400 will respond to a Link_on packet addressed to it received on the bus. The packet has the following format: Figure 2.3 0 1 Link_on packet format phy_ID 0000 0000 0000 0000 0000 0000 logical inverse of first quadlet If the logical AND of the LPS pin and the Link_active bit is zero, then the SBPH400 will generate a 6.144 MHz signal on the LKON pin, until this logical value becomes 1. Otherwise the packet is forwarded to the local link. Note that all Link_on packets received on the bus are forwarded to the local link if it is active, whether or not the packets are addressed to the local node. 2.7.4 PHY configuration packet The SBPH400 will respond to every PHY configuration packet which it receives on the bus, or from the link device for transmission on the bus. The packet has the format shown in Figure 2.4: 12/43 2 SBPH400-3 Figure 2.4 0 0 PHY configuration packet format root_ID R T gap_cnt 0000 0000 0000 0000 logical inverse of first quadlet The fields in the PHY configuration packet are interpreted as shown in Table 2.2. Table 2.2 PHY configuration packet fields Field root_ID Definition physical ID Comment the physical node identifier of the node to become root on next reset R set root The Force_Root bit in the SBPH400 is set if R=1 and root_ID = the node_ID of this node T set gap count gap_cnt Gap_Count value If T=1, then the value of the gap count register in the SBPH400 is set to gap_cnt. new value of Gap Count register Note that either or both of R and T must be set to 1. 2.7.5 Ping packet The SBPH400 supports the use of ping timing. The ping packet has the format shown in Figure 2.5: Figure 2.5 0 0 Ping packet format phy_ID 0 0 type (0) 00 0000 0000 0000 0000 logical inverse of first quadlet When the SBPH400 receives a ping packet from the bus or from the local link addressed to the node, it responds immediately (without arbitration) with a Self_ID packet to both the bus and the local link. 2.7.6 Remote Access and Reply The SBPH supports remote access to its internal registers. On receipt of a remote access packet addressed to the node (either from the bus or from the local link), the SBPH400 will immediately respond with the appropriate remote reply packet. The remote access packet and the reply packet are also forwarded to the local link. 13/43 2 SBPH400-3 Figure 2.6 0 0 Remote access packet format phy_ID 0 0 type page port reg reserved reg data logical inverse of first quadlet Figure 2.7 0 0 Remote reply packet format phy_ID 0 0 type page port logical inverse of first quadlet The fields in the remote access and remote reply packets are interpreted as shown in Table 2.3. Table 2.3 Remote Access and Remote Reply packet fields Field Comment phy_ID Physical node identifier of the destination of the packet (type = 1 or 5) Physical node identifier of the source of the packet (type = 3 or 7) 1 - register read of the base registers 3 - register contents (base registers) 5 - register read of the paged registers 7 - register contents (paged registers) 0 - Port Status Page 1 - Product Identification Page 2-7 - (these pages not implemented, always responds with zero) type page port reg data Identify the port for the selected register page. For values 0, 1 and 2, the page is as defined in Table 2.17. For all other values the SBPH400 always responds with zero. If type = 1, then reg directly addresses one of the base registers. If type = 5, then reg addresses 10002+reg in the selected page and port. Current value of the SBPH400 register addressed by the immediately preceding Remote Access packet (reserved and unimplemented fields and registers are returned as zero). 2.7.7 Remote Command and Confirmation packets The SBPH400 responds to remote command packets by initiating the appropriate action and immediately sending a remote confirmation packet. Figure 2.8 0 0 Remote command packet format phy_ID 0 0 type(8) 000 port logical inverse of first quadlet 14/43 2 0000 0000 cmnd SBPH400-3 Figure 2.9 0 0 Remote confirmation packet format phy_ID 0 0 type(A16) 000 port 000 f c b d ok cmnd logical inverse of first quadlet The fields in the remote command and remote confirmation packets are interpreted as shown in Table 2.4. Table 2.4 Remote Command and Confirmation packet fields Field phy_ID Comment Physical node identifier of the destination of the packet (type = 8) Physical node identifier of the source of the packet (type = A16) type 8 - remote command packet A16 - remote confirmation packet Identify the port for the command or confirmation. For values other than 0, 1 and 2, the SBPH400 always responds with the OK bit set to zero in the confirmation packet. port f current value of the Fault bit from SBPH400 register 10012 for the addressed port c b current value of the Connected bit from SBPH400 register 10002 for the addressed port current value of the Bias bit from SBPH400 register 10002 for the addressed port d ok current value of the Disabled bit from SBPH400 register 10002 for the addressed port 1 if the immediately preceding remote command was accepted by the SBPH400, zero otherwise cmnd type = 8:0 - NOP 1 - Transmit TX_DISABLE_NOTIFY then disable the port 2 - Initiate suspend 4 - Clear the port’s Fault bit 5 - Enable port 6 - Resume port type = A16:The cmnd value from the immediately preceding remote command packet data Current value of the SBPH400 register addressed by the immediately preceding Remote Access packet (reserved and unimplemented fields and registers are returned as zero). 2.8 Link interface 2.8.1 Overview The link interface in the SBPH400 operates as described in the IEEE P1394a proposal. The SBPH400 implements an interface to a single 1394 link layer device, using the pins D[0:7], Ctl[0:1], LREQ, SClk, LPS and LKON. The interface is scalable, using 2 data bits in parallel per 100 Mbit/sec. This enables the clock rate of the signals at this interface to remain at 50 MHz. 15/43 2 SBPH400-3 The SBPH400 has control over the bidirectional pins. It will, upon request, transfer this control to the link device, which can then drive these pins. The 8 bidirectional data pins D[0:7] form the data bus. The portion of the D bus which carries packet data is left-justified starting with the 0 bit. Packet data for 100 Mb/s transfers uses D[0:1], 200 Mb/s transfers use D[0:3], and 400 Mb/s transfers use D[0:7]. The unused D[n] signals are transmitted as ‘0’ and are ignored when the link device has control of the bus. The control bus CTL[0:1] carries the control information. The LREQ pin is used by the link device to request access to the serial bus and to read and write the chip registers. 2.8.2 Types of operation The four basic operations which may occur at the PHY-Link interface are: request, status, transmit and receive. Request is the only operation initiated by the link layer device. The link layer device uses the request operation to read or write a register located in the SBPH400 or to request the bus so that the SBPH400 can initiate a transmit action on the bus. The SBPH400 initiates a receive action whenever a packet is received from the serial bus and a status indication to notify events to the link layer device. 2.8.3 Control pins When the SBPH400 has control of the PHY-Link interface the CTL[0:1] lines are encoded as shown in Table 2.5. Table 2.5 CTL[0:1] When the SBPH400 is driving CTL[0:1] 00 NAME Idle DESCRIPTION No activity (default mode) 01 10 Status Receive The SBPH400 is sending status information to the link device An incoming packet is being transferred from the SBPH400 to the link device 11 Grant The link device is granted the bus to send a packet When the link layer device has been granted the PHY-Link interface by the SBPH400, it should encode the CTL[0:1] lines Table 2.6 Table 2.6 CTL[0:1] when the link is driving (upon grant from SBPH400) 00 NAME Idle DESCRIPTION The link device has released the bus (normally after transmission). Note that multiple Idles may need to be transmitted. 01 Hold 10 Transmit The link device is preparing data or wishes to reacquire the bus without arbitrating to send another packet The link device is sending a packet to the SBPH400 11 unused 16/43 2 SBPH400-3 2.8.4 Link device request (LREQ) The link layer device requests the bus or accesses a register in the SBPH400 by sending a short serial stream on the LREQ pin. The information sent includes the type of bus request, the speed at which the packet is to be sent, or a read or write command. The length of the request stream depends on whether it is a bus request (8 bits), a read register request (9 bits), a write register request (17 bits), or an accelerate control request (6 bits). The request stream always commences with a start bit (value 1b) and terminates with a stop bit (0b). Bit 0 is transmitted first on the serial request stream. The LREQ timing and the definition of the bits in the transfer are shown in Figure 2.10 Figure 2.10 LREQ timing LR0 LR1 LR2 LR3 LR(n-2) LR(n-1) The Bus Request is 8 bits long and is specified in Table 2.7. (Note that this is backwards compatible with the 7-bit format as specified in IEEE 1394-1995, which is also supported by the SBPH400.) Table 2.7 Bus request format Bit(s) 0 Name Start_Bit Description Indicates start of transfer. Always 1. 1-3 Request_Type 4-6 Request_Speed Indicates the type of bus request being performed. See Table 2.12 for the encoding of this field. Indicates the speed at which the SBPH400 will be sending the packet for this request. This field has the same encoding as the speed code from the first symbol of the receive packet. See Table 2.11 for the encoding of this field. 7 Stop_Bit Indicates end of transfer. Always 0. The Read Request is used to read a register in the device. It is 9 bits long and is specified in Table 2.8. Table 2.8 Read register request format Bit(s) Name Description 0 1-3 Start_Bit Request_Type Indicates the start of transfer. Always 1. 100b (Register read) 4-7 Address Indicates the address of the physical register to be read. 8 Stop_Bit Indicates end of transfer. Always 0. 17/43 2 SBPH400-3 The Write Request is used to write to a register in the device. It is 17 bits long and is specified in Table 2.9. Table 2.9 Write register request format Bit(s) Name Description 0 1-3 Start_Bit Request_Type Indicates the start of transfer. Always 1. 101b (Register write) 4-7 Address Indicates the address of the physical register to be written. 8-15 Data Indicates the data to be written to the specified physical register. 16 Stop_Bit Indicates end of transfer. Always 0. The Accelerate Control Request is used to control the use of arbitration acceleration in order to prevent Cycle Start packet starvation. It is 6 bits long and is specified in Table 2.10 Table 2.10 Accelerate control request format Bit(s) 0 Name Start_Bit Description Indicates the start of transfer. Always 1. 1-3 4 Request_Type Acceleration_Select 110b (AccCtrl) 0 = Decelerate 1 = Accelerate 5 Stop_Bit Indicates end of transfer. Always 0. The Request Speed field in the bus request is encoded as specified in Table 2.11: Table 2.11 Request speed field LR[4:6] 000 Data Rate S100 001 010 not supported (S1600) S200 011 not supported (S3200) 100 S400 101 110 reserved not supported (S800) 111 reserved 18/43 2 SBPH400-3 The Request Type field is encoded as specified in Table 2.10: Table 2.12 Request type field LR[1:3] Name Description 000 ImmReq 001 IsoReq Used for Acknowledge Transfers. The SBPH400 takes control of the bus immediately upon detecting idle without arbitration. Used for Isochronous Transfers. The SBPH400 arbitrates after an isochronous gap, or transmits immediately if an isochronous packet has just been received from a child port (fly-by arbitration). The SBPH also performs accelerated arbitrations (see AccCtrl below) after receiving this request if the enab_accel register is set to 1. 010 PriReq 011 FairReq 100 RdReg 101 WrReg Write to specified register. 110 AccCtrl Accelerate control. The link should send an AccCtrl request with Acceleration_Select = 0 (Decelerate) if it is not root and when its cycle timer has counted a 125 µs interval. The SBPH400 will not employ ACK accelerated arbitration or fly-by arbitration for asynchronous packets until a subsequent Accelerate request with Acceleration_Select = 1 (Accelerate) is received or an IsoReq has been received. The link should send an Accelerate request with Acceleration_Select = 1 after it has received a cycle start packet if it has no isochronous packets to transmit in the current isochronous cycle. 111 reserved ignored Used for Cycle Master requests. The SBPH400 arbitrates after a subaction gap or, if acceleration enhancements are enabled (enab_accel register is set to 1) and if accelerate control has been set to allow accelerations (see AccCtrl below), arbitrates after an ACK packet has been received, or transmits immediately if an ACK packet has just been received on a child port (see Accelerate/Decelerate below), ignoring the fair protocol. This is also used for the second and subsequent optimized fair transfers Used for Fair Transfers. Used for Fair Transfers. The SBPH400 normally arbitrates after subaction gap. If acceleration enhancements are enabled (enab_accel register is set to 1) and if accelerate control has been set to allow accelerations (see AccCtrl below), then the SBPH400 will arbitrate after an ACK packet has been received, or transmit the packet immediately if an ACK packet has been received on a child port. In all cases the SBPH400 follows the fair protocol (one FairReq packet per arbitration reset gap). Return specified register contents through a status transfer. Note that the result is undefined if a previous RdReg request has not been completed. 19/43 2 SBPH400-3 2.8.5 Bus request The SBPH400 obeys the rules specified in the P1394a proposal for the disposition of requests received from a link device, provided that the link device follows the P1394a rules for when it may issue requests. The link device sends the request for the bus for fair (FairReq) or priority (PriReq) access at least one clock after the interface becomes idle or during a status transfer from the SBPH400. A cycle master node uses a priority request (PriReq) to send the cycle start packet. A receive state (CTL[0:1]=10) at any time during or after the link device sends a fair or priority request transfer indicates to the link device that the request cannot yet been granted, due to the arrival of an incoming packet. If arbitration acceleration is enabled, and the incoming packet is null or has no more than 8 bits, then the SBPH400 retains the request, otherwise the request is discarded as soon as the SBPH400 determines that the incoming packet has more than 8 bits. The request always discarded if arbitration acceleration is not enabled. The link device should reissue a discarded request on the next idle or status. A link device uses the IsoReq request at any time to request the SBPH400 to send an isochronous packet. The SBPH400 will wait for a an isochronous gap before arbitrating for the bus. The SBPH400 will clear the request only when the bus has been won, or if it performs a status transfer indicating a subaction gap (this indicates an error condition and should not occur). A link device must issue a ImmReq request to send an acknowledge packet during the reception of a packet addressed to it or no later than the fourth SClk cycle after the interface went idle. As soon as the packet reception ends the SBPH400 immediately takes control of the bus and grants the bus to the link device. If the header CRC of the packet happens to be bad the link device should release the bus immediately. Note that the link device should not use this request to send another type of packet. This can be ensured by making the link device wait for 160 ns after the end of the receive packet to allow the SBPH400 to grant it the bus for the acknowledge. The bus is then released before starting another request. After the link issues a request for the access to the bus (immediate, iso, fair, or priority) it cannot issue another bus request until the SBPH400 indicates that the request is either “lost” (incoming packet, other than an ACK packet when accelerations are enabled) or “won” (grant). When a previous bus request is pending the SBPH400 ignores new bus requests. All outstanding requests are cancelled on a bus reset. 2.8.6 Register Read/Write requests For write requests, the SBPH400 takes the data field of the LREQ transfer and loads it into the addressed register as soon as the transfer is complete. For read requests, the SBPH400 returns the contents of the addressed register at the next opportunity through a 16-bit status transfer. The link device may perform a read or write register operation at any time. 20/43 2 SBPH400-3 2.8.7 Status transfer A 4-bit status transfer of S[0:3] is initiated by the SBPH400 when any of the four status bits S[0] to S[3] (as specified in Table 2.13) is set to 1. A 16-bit status transfer of s[0] to s[15] (as specified in Table 2.13 is initiated by the link in response to a register read request from the link device, or to indicate the node’s new phy_ID after a bus reset during the Self_ID process. After the link interface is idle, a status transfer is initiated with the assertion of status (CTL[0:1] = 10) condition by the SBPH400. The first two bits of status information (S[0:1]) are made available on D[0:1]. The status condition is held on CTL[0:1] for the duration of transfer. The SBPH400 ensures that there is at least one clock cycle between status transfers. Table 2.13 Status bits Bit (S[n]) 0 Name ArbitrationResetGap Description This bit indicates that the SBPH400 has detected that the serial bus has been idle for an arbitration reset gap time (this is defined in the IEEE 1394 standard). This bit is used by the link device in the busy/retry state machine. This bit is reset after the status transfer or when a transfer occurs on the bus. 1 SubactionGap 2 BusReset This bit indicates that the SBPH400 has detected that the serial bus has been idle for a subaction gap time (this is defined in the IEEE 1394 standard). This bit is used by the link device to detect the end of an isochronous cycle. This bit is reset after a status transfer or when a transfer occurs on the bus. This bit indicates that the SBPH400 has entered the bus reset state. This bit is reset after a status transfer 3 PHY_Interrupt 4-7 Address 8-15 Data Figure 2.11 This bit is set whenever any of the interrupt-generating status bits (Loop detect, Power fail, State time-out, Port event) is set to 1. This bit is reset after a status transfer. These bits indicate the address of the SBPH400 register whose contents are being transferred to the link device These bits provide the current value of SBPH400’s register. Status transfer timing SBPH400 CTL[0:1] 00 01 01 01 00 00 S[0,1] S[2,3] S[14,15] 00 SBPH400 D[0:1] 21/43 2 SBPH400-3 In the event of a packet reception during status transfer, the SBPH400 prematurely ends the transfer by removing the status indication on the CTL[0:1]. Note that any status bits transferred will be reset, even if the status transfer is prematurely terminated (i.e. if it is terminated after the transfer of S[0:1], then S[0:1] will be reset. If it is terminated after the transfer of S[0:n] where n>=3, then S[0:3] will be reset. The status transfer will be retried at the next available opportunity if it was a 16 bit status transfer, or if it was a 4 bit status transfer and at least one of the four status bits S[0] to S[3] is (still) 1. 2.8.8 Transmit The link device requests access to the serial bus through LREQ when it wants to transmit information. The SBPH400 arbitrates, using the timing algorithm appropriate to the request type, to gain access to the serial bus. After the SBPH400 wins the arbitration, it grants the bus to the link device by asserting grant on the CTL pins for one clock cycle, followed by idle for one clock cycle. When it receives control of the bus, the link may assert one cycle of idle on the CTL pins (this may be advisable when using PHY-Link isolation). While preparing data, the link device keeps the ownership of the bus by asserting hold on the CTL pins. It is not necessary for the link device to assert hold if it is ready to transmit as soon as bus is granted. When it is ready to transmit a packet, the link device asserts transmit on the CTL pins along with the first bits of the packet. After sending the last bits of the packet when the link device does not wish to concatenate another packet, the link device asserts idle on the CTL pins for two clock cycles before tristating the CTL pins. After sending the last bits of the packet when the link device wishes to concatenate another packet, the link device asserts hold on the CTL pins for one cycle, together with the speed code for the next packet, followed by a single cycle of idle before tristating the CTL pins. The link device may release the bus after the SBPH400 has asserted grant by asserting idle on the CTL pins for three cycles, and may release the bus after asserting hold by asserting idle on the CTL pins for two cycles. The hold state indicates to the SBPH400 that the link device wants to send another packet without releasing the bus (a concatenated packet). The SBPH400 responds to the hold by waiting the required minimum time and then asserts transmit as before. The speed of the concatenated packet is indicated at the time that the hold state is asserted, using the encoding specified in Table 2.14. Note that it is not permitted to transmit a S100 packet as a concatenated packet after transmitting a higher speed packet. Note that, for compatibility with 1394-1995 PHYs, P1394a requires that if “multi-speed concatenated packets” is not enabled (see Table 2.16), the speed code for any concatenated packet which is received from the link will be ignored, and the packet will be transmitted at the same speed as the packet to which it is concatenated. The SBPH400 will supply the appropriate speed code as it transmits the packet on the bus. When the link device has finished sending the last packet of the current bus ownership, it releases the bus by asserting idle on the CTL pins for two consecutive clock cycles. The transmit timing is shown in Figure 2.12. 22/43 2 SBPH400-3 Figure 2.12 Transmit timing Single Packet SBPH400 CTL[0:1] 00 11 00 ZZ ZZ ZZ ZZ ZZ ZZ ZZ ZZ ZZ ZZ ZZ ZZ ZZ ZZ ZZ ZZ 01 01 10 10 10 00 00 ZZ 00 00 D0 D1 Dn 00 00 ZZ SBPH400 D[0:7] 00 00 00 ZZ ZZ LINK DEVICE CTL[0:1] ZZ ZZ ZZ 00 LINK DEVICE D[0:7] ZZ ZZ ZZ 00 Optional idle cycle Concatenated packet SBPH400 CTL[0:1] ZZ ZZ ZZ 00 00 11 00 ZZ ZZ ZZ ZZ ZZ ZZ 00 00 00 00 ZZ ZZ ZZ ZZ ZZ ZZ ZZ ZZ ZZ 00 01 01 10 10 ZZ ZZ ZZ ZZ 00 00 00 D0 D1 SBPH400 D[0:7] ZZ ZZ LINK DEVICE CTL[0:1] 10 01 00 LINK DEVICE D[0:7] Dn SP 00 Optional idle cycle 23/43 2 SBPH400-3 2.8.9 Receive When the SBPH400 detects the “data-on” state on the serial bus, it starts the receive operation by asserting receive on the CTL pins and ‘1’ on each of the D pins. The SBPH400 indicates the beginning of the packet by placing on the D pins the speed code, as defined in Table 2.14. The speed code is followed by the contents of the received packet using the appropriate range of D pins (D[0:1] for S100, D[0:3] for S200 and D[0:7] for S400). The CTL pins will remain in the receive state until the last symbol of the packet has been transferred to the link device. The end of the packet is indicated by the CTL pins going back to the idle state. Note that the speed code is part of the link interface protocol and is not included in the calculation of CRC. Note that P1394a requires that, for compatibility with 1394-1995 PHYs, if “multi-speed concatenated packets” is not enabled (see Table 2.16), any concatenated packet which is received without a speed code is assumed to be transmitted at the same speed as the packet to which it is concatenated. If the SBPH400 detects such a packet then it will indeed make this assumption, and will supply the appropriate speed code in front of the packet as it transfers it to the link device. The receive timing is shown in Figure 2.14. Table 2.14 Figure 2.13 Speed codes on the LINK-PHY interface D[0:7] 00000000 Data Rate S100 01000000 S200 01010000 S400 11111111 “data-on” indication Receive timing CTL[0:1] 00 D[0:7] (hex) 24/43 2 00 10 FF 10 10 10 10 10 00 00 FF SP D0 D1 Dn 00 00 SBPH400-3 2.8.10 SBPH400 registers The accessible SBPH400 registers are listed in Table 2.15. The descriptions of the fields are given in Table 2.16. Table 2.15 Accessible SBPH400 register Address 0000 0 1 0001 RHB IBR 0010 0011 0100 0101 2 3 Physical_ID 0110 0111 C ISBR rsv rsv 000b (Jitter) Loop Pwr-fail Page_select 1000-1111 Table 2.16 Field Physical_ID 5 6 R 7 PS Gap_count 111b (Extended) Max speed Link_active Resume_ int 4 0011b (Total ports) 0000b (Delay) State t_out rsv rsv Power_class Port Enab_ Enab_ event accel multi Port_select Register 0-7 [Page_select] SBPH400 register fields Size 6 Type Description R The address of the node determined during self-identification. R PS 1 1 R R When set to 1, indicates that the node is the root. Cable power status. This value always reflects the filtered voltage sensed on the CPS pin. Root Hold-off bit. When set to 1, instructs the node to attempt to become the root during the next Tree-ID process. Value on power reset is 0. RHB 1 R/W IBR 1 R/W Gap_Count 6 R/W Extended 3 R Total_Ports 4 R Always reads as 111b to indicate use of the extended PHY register map Always reads as 3 Max_Speed Delay 3 4 R R 010b (maximum speed is S400) 0000b (maximum repeater delay is 144 ns) Link_active 1 R/W Set or cleared by software. Note that the value of the L bit transmitted in the self-ID packet is the AND of the Link_active bit and the LPS pin. Initialized to the value of the LACT configuration pin on power reset. C 1 R/W Jitter 3 R Contender. Set or cleared by software to control the value of the C bit transmitted in the self-ID packet. On power reset this is initialized to the value of the CMC pin. 000b (fastest and slowest repeater delay differ by 20ns) Initiate Bus Reset bit. When set to 1, instructs the SBPH400 to initiate a bus reset for 166 µsec immediately. Always reads as zero. Arbitration timer setting. Used to optimize gap times based on the topology of the network. 25/43 2 SBPH400-3 Table 2.16 Field SBPH400 register fields (continued) Size Type Description Power_class 3 R/W Resume_int 1 R/W ISBR 1 R/W Initiate short (arbitrated) bus reset. Unless entry to suspend or resume is in progress for any of the SBPH400’s ports, a write of one to this bit requests the SBPH400 to arbitrate after a sub-action gap and issue a short bus reset. Any outstanding fair request is abandoned. Unlike fair bus requests, the request persists until won, or until a time-out forces a long bus reset. Always reads as 0. Loop 1 R/W Loop detect interrupt. Set to one when the Tree-ID process detected a loop. The PHY_interrupt status bit is set when this bit transitions from 0 to 1. A register write with the value 1 in the field corresponding to this bit clears the register to zero. A register write with a value 0 to the field corresponding to this bit is ignored. Pwr_fail 1 R/W Cable power fail interrupt. Set when the PS register changes from 1 to 0. The PHY_interrupt status bit is set when this bit transitions from 0 to 1. A register write with the value 1 in the field corresponding to this bit clears the register to zero. A register write with a value 0 to the field corresponding to this bit is ignored. State t_out 1 R/W Port_event 1 R/W Enab_accel 1 R/W State time-out interrupt. Set to 1 when the arbitration state machine has been in any state other than Idle, Tree-ID state T0, Transmit or Receive for longer than 300µsec. The PHY_interrupt status bit is set when this bit transitions from 0 to 1. A register write with the value 1 in the field corresponding to this bit clears the register to zero. A register write with a value 0 to the field corresponding to this bit is ignored. Port event detect. Set to 1 when any of Connected, Bias, Disabled or Fault change for a port whose Int_enable bit is one, or when resume operations commence for any port and Resume_int is set to 1. The PHY_interrupt status bit is set when this bit transitions from 0 to 1. A register write with the value 1 in the field corresponding to this bit clears the register to zero. A register write with a value 0 to the field corresponding to this bit is ignored. Enable ACK accelerated and fly-by arbitration. Initialized to 0 on power reset. Enab_multi 1 R/W 26/43 2 Power class. Set by software to control the value of the pwr field transmitted in the self-ID packet. On power reset, this is initialized to the values of the PC[0:2] pins. Resume interrupt enable. When set to 1, the SBPH400 sets Port_event to 1 if resume operations commence for any port. Initialized to 0 on power reset. Enable multi-speed packet concatenation. Initialized to 0 on power-on reset. SBPH400-3 Table 2.16 Field SBPH400 register fields (continued) Size Type Description Page_select 3 R/W Select extended register page for a subsequent PHY register read or write operation. 0 = Port Status Page 1 = Product Identification Page Initialized to 0 on power reset. Port_select 4 R/W Identify the port for the selected register page for a subsequent PHY register read or write operation. For values 0, 1 and 2, the page is as defined in Table 2.17. For all other values, a subsequent write to any register in the page has no effect, and a subsequent read from any register in the page returns zero. Initialized to 0 on power reset. Field reserved in P1394a for future use. No effect on write, always reads as zero. rsv R/W Table 2.17 Port status page Address 1000 0 1 2 AStat 1001 4 Child Int_ enable Fault BStat Negotiated_speed 1010-1111 Table 2.18 3 5 Con 6 Bias 7 Dis rsv rsv Port status register fields Field Size Type Description AStat 2 R TPA line state on the selected port (112 = Z, 012 = 1,102 = 0, 002 = invalid). BStat 2 R TPB line state on the selected port (112 = Z, 012 = 1,102 = 0, 002 = invalid). Child 1 R If 1 the corresponding port is a child, else parent (only valid after Self_ID) Con 1 R Bias 1 R If 1 the corresponding port is connected, 0 if the port is disconnected. Reflects the Bias detected status on the port (1 = Bias detected) after filtering Dis 1 R/W Negotiated_speed 3 R The port is disabled when this bit is set to 1, and enabled when this bit is set to 0. Initialized to the value of the PDISABLE pin on power reset. The negotiated speed for this port (only valid after Self_ID). Possible values are 000b (S100), 001b (S200), 010b (S400) 27/43 2 SBPH400-3 Table 2.19 Product identification page Address 1000 0 1 2 3 4 5 1 (Compliance level = P1394a) 1001 6 7 rsv 1010 0 Manufacturer’s OUI (MSB - 0016) 0 0 0 0 0 0 1 0 Manufacturer’s OUI (8016) 0 0 0 0 0 0 1 1 1 0 1 0 1011 1100 Manufacturer’s OUI (LSB - E116) 1101 0 0 0 0 Division (0816) 1 0 1110 1111 0 0 0 0 0 0 0 Product- LSB (0116) 0 0 Major revision (1) 0 0 0 Prod-MSB (0) 0 0 0 1 Minor revision (see note) 1 X X X X The 6-bit Division field identifies the product group within SGS-THOMSON. The 10 bit Product field identifies the product within the Division. The Major revision will increment with each major revision of the device. The minor revision will start at 0 for each major revision and will increment with mask fixes, etc. Note: The Division and Product fields are identical to the corresponding fields when accessing the SBPH400 via the JTAG Test Access Port. 2.9 Reset and initialization 2.9.1 Power on Figure 2.14 SBPH400 reset timing E x t os c illator ( w here use d) R e set# SBP H 400 operational 100 ns m in (V D D present) 28/43 2 500 µ s ec SBPH400-3 On Power on, the Reset# pin should be held low for 2ms to allow supplies to settle. To reset the device when VDD is already present, the Reset# pin should be held low until a minimum of 100ns after the external oscillator (if used) is started and operating within specification. The SBPH400 will wait for approximately 500 µsec to allow its internal clocking circuitry to stabilize. At the end of the nominal 500 µsec period, the SBPH400 becomes fully operational. Prior to the SBPH400 becoming fully operational, all outputs on the PHY/Link interface are held in high impedance, as are the TpBias and TPA and TPB pins for all three ports. When the SBPH400 becomes fully operational, it senses the ISO, PC[0:2], CMC, LACT and PDISABLE. If ISO = 0, then all outputs on the PHY/Link interface are taken to zero, and the SBPH400 will also then respond to LPS if this pin is active (see 2.9.2). 2.9.2 PHY/Link Interface start-up The PHY/Link interface is controlled by the link device via the LPS signal. In order to indicate to the SBPH400 that the link interface is active, LPS should either be held to a logic 1 (possibly by connecting to the VD D supplying the link layer device) or be connected to a pulsed output which meets the specification shown in Figure 2.15 and Table 2.20. If neither of these is true after power reset (see above), then no signal is considered to be received on LPS, the link interface continues to be disabled, and the SBPH400 operates as a PHY repeater. Figure 2.15 LPS timing (isolated interface) LPS (isolated) TLPSH Table 2.20 TLPSL LPS timings Symbol Parameter TLPSL TLPSH LPS low time (isolated interface) LPS high time (Isolated interface) Unit Min ns ns 90 90 Typ Max 1000 1000 When LPS is asserted, the PHY/Link interface starts as illustrated in Figure 2.16 29/43 2 SBPH400-3 Figure 2.16 PHY/Link interface start-up timing LPS SC lk (direct) SC lk (is o) C [0:1], D[0:7] (direct) C [0:1], D[0:7] (iso) 5 ns (m in) 40 - 60 ns (S BP H 400 operational) 500 µ s nom inal (SBPH 400 suspended) When LPS is reasserted, the SBPH400 resumes sending SCLK (if necessary) after 40-60 ns if the SBPH400 is operational, or otherwise after a nominal period of 500 µsec if LPS is used to bring the SBPH400 out of suspend. If the interface is operating in direct mode (ISO = 0) then Ctl[0:1] and D[0:7] are held zero. If the interface is operating in isolated mode (ISO = 1), then the SBPH400 maintains high impedance for the first cycle of SCLK, asserts zeros on Ctl[0:1] and D[0:7] for the second cycle of the resumed SCLK, and maintains high impedance for cycles 3 to 7. The SBPH400 asserts a nominal receive indication on Ctl[0:1] for the eigth cycle, while simultaneously indicating data_prefix on D[0:7] (all 1’s). This is maintained for further cycles if the SBPH400 is in a state where it would otherwise be transferring data. 2.9.3 PHY/Link interface reset and disable The PHY-Link interface may be reset by taking LPS low for a minimum of 2.75 µsec, but less than 25 µsec. During this time the Ctl[0:1] and D[0:7] signals are disabled, but the SBPH400 continues to provide SCLK. If neither of these is true for a period greater than 25 µsec, then no signal is considered to be received on LPS, the link interface is disabled, and the SBPH400 operates as a PHY repeater. When the link interface is disabled, all outputs are held to zero if the interface is operating in direct mode (ISO = 0), otherwise (ISO = 1) all outputs are maintained in high impedance. The 30/43 2 SBPH400-3 timing parameters are given in Table 2.21, and the signal relationships are illustrated in Figure 2.17 and Figure 2.18. Table 2.21 PHY/Link interface reset and disable timing parameters Symbol TLPS_RESET Parameter Time for SBPH400 to recognize LPS logically deasserted and reset the interface Unit µs Min 1.2 TLPS_DIS Time for SBPH400 to recognize LPS logically deasserted and disable the interface µs 25 30 TRESTORE Time to permit the optional differentiator and isolation circuits to restore during an interface reset µs 15 20 Figure 2.17 Typ Max 2.75 PHY-Link reset timing SCLK T LPS_RESET TRESTORE LPS LPS (isolated) DATA CTL LREQ Figure 2.18 PHY-Link disable timing SCLK T LPS_DISABLE TRESTORE LPS LPS (isolated) DATA CTL LREQ 31/43 2 SBPH400-3 2.9.4 LKON (link on) The LKON pin is used as an output to indicate that the SBPH400 has received a Link_On packet. If the there is no signal on the LPS pin (indicating that the link device is not currently powered) or the Link_active register is zero (link interface turned off by software) and a Link_On packet is received addressed to the node, then a 6.144 MHz signal is output on the LKON pin. This signal is turned off within 500 ns when both there is a signal received on LPS and the Link_active register is 1. 2.10 ISO (isolation) The SBPH400 supports the use of an isolation barrier between the chip and a link device. If ISO is set high, then the an internal pulsed differentiating function is used on the CTL[0:1] and the D[0:7] pins when used as outputs. Appropriate threshold circuitry is included on these pins when used as inputs to interpret differentiated signals correctly. The differentiation circuitry transmits a 1 or a 0 when there is a logical transition to 1 or 0 respectively, otherwise the output is set to high impedance. This is shown in Table 2.22. This allows an arbitrary sequence of 1’s or 0’s to be transmitted across an AC coupled isolation interface. Table 2.22 Output differentiation for isolation Next 0 1 Z 0 1 Z Previous 0 1 2.11 CPS (cable power status) This input should be connected to the power supply provided from the cable via an external series 400 KOhm resistor. The internal logic associated with this pin provides a nominal filtered cable power fail voltage (as applied to the external resistor) threshold of 6.25 volts. The internal logic will report 1 in the PS register when the external voltage on the resistor exceeds the threshold, and will report 0 in the PS register when the external voltage falls below the threshold. A transition from 1 to 0 on the value in the PS register causes the Pwr_fail register to be set to 1, which in turn will cause a link status transfer with the PHY_Interrupt bit set if the Link interface is active, otherwise will cause a LinkOn signal. Appropriate protection is incorporated in the SBPH400 for cable power voltages within the 1394 specification applied via the external series resistor. 32/43 2 SBPH400-3 3 Pin Description Table 3.1 Pin description - normal operation Pin name AGND Pin number 15, 23, 25, 80 AVDD 6, 24, 26, 79 CLK24 CMC 38 64 I I External 24.576 MHz oscillator input (optional, see QX0) Configuration Manager Contender. Used to initialize the C register at power-on reset. It should be programmed by connecting it to VDD (C=1) or GND (C=0). CPS 78 I Cable power status. 46, 45 I/O Control signals for PHY-Link interface D[0:7] DGND 59 - 51 12, 13, 14, 27, 28, 29, 30, 31, 34, 40, 43, 48, 49, 50, 61, 69, 70, 72, 73, 74 I/O Data signals for PHY-Link interface Digital Ground DVDD 32, 33, 47, 71 CTL[0:1] I/O Description Analog Ground Analog Supply Voltage Digital Supply Voltage ISO 68 I LACT 41 I LKON 42 O Link on o/p LPS LREQ 62 44 I I Link power status. Link request to SBPH400 35, 75, 76 I OGND 37 I Inputs not used in normal operation, may be connected to VDD or GND, or left unconnected. Oscillator ground OVDD PC[0:2] 39 65 - 67 I I Oscillator supply voltage Power Class input PDISABLE 63 I QX0 38 I Ports disable. Used to initialize all three ports as disabled on power-on reset. 24.508 MHz crystal input 0 (optional, see CLK24) QX1 36 I 24.508 MHz crystal input 1 (optional, left unconnected if not used, must not be taken to power or GND) External resistor for bias current setting I Reset. Taking this signal low causes all activity to cease. When this signal is taken high, all appropriate registers and outputs are initialized to their power reset values and a 166µsec bus reset is initiated. N/C R[0:1] RESET# 22, 21 77 Link interface isolation logic control. Logic level 1 on this pin enables the isolation logic, 0 disables the isolation logic (normally tied to VDD or GND as required) Link Active. Used to initialize the Link Active register on power reset. It should be programmed by connecting it to VDD (Link Active = 1) or GND (Link Active = 0). 33/43 2 SBPH400-3 Table 3.1 Pin name Pin description - normal operation (continued) Pin number I/O Description SCLK TPA1 60 1 O I/O Clock to Link device - 49.152 MHz Positive signal of cable pair A of port 1 TPA1# TPB1 2 3 I/O I/O Negative signal of cable pair A of port 1 Positive signal of cable pair B of port 1 TPB1# 4 I/O Negative signal of cable pair B of port 1 TPA2 7 I/O Positive signal of cable pair A of port 2 TPA2# TPB2 8 9 I/O I/O Negative signal of cable pair A of port 2 Positive signal of cable pair B of port 2 TPB2# TPA3 10 16 I/O I/O Negative signal of cable pair B of port 2 Positive signal of cable pair A of port 3 TPA3# 17 I/O Negative signal of cable pair A of port 3 TPB3 18 I/O Positive signal of cable pair B of port 3 TPB3# TPBIAS1 19 5 I/O O Negative signal of cable pair B of port 3 Cable Termination voltage source for port 1 TPBIAS2 TPBIAS3 11 20 O O Cable Termination voltage source for port 2 Cable Termination voltage source for port 3 Some pins on the SBPH400 have different functionality in various test modes. Table 3.2 identifies these pins for ease of reference, but the full description of the associate functions is not included in this data sheet. Table 3.2 Pin description - test pins Pin name Pin number I/O CLK98 PLLDIS 35 49 I I 98.304 MHz Oscillator input, used when PLLDIS is tied to VDD Internal PLL disable pin. Tie to VDD to disable internal PLL. 76, 67, 65 68, 66, 64 I I Used to serially shift data into the SBPH400 for production test Used to serially shift data out of the SBPH400 for production test TCK 72 I TDI 75 I Test clock. Used to clock data into and out of the SBPH400 during operation of the Test Access Port or production test. Test Data Input. Used to serially shift test data and test instructions into the SBPH400 during TAP operations. TDO 63 O TEST ENABLE 70 I TESTMODE TMS 30 69 I I Reserved for production test Test Mode Select. This signal controls the state of the TAP controller within the SBPH400. TRST# 40 I Test Reset. Resets the TAP controller. SCI[0:2] SCO[0:2] 34/43 Description Test Data Output. Used to serially shift test data and test instructions out of the SBPH400 during TAP operations. Reserved for production test SBPH400-3 4 Electrical Specifications 4.1 Absolute maximum ratings Table 4.1 Absolute maximunm ratings Symbol VDD Parameter Supply Voltage VINL VINH Logic signal input low level Serial signal input level T°CMAX Note: Units V Min 0 V V -0.5 Max 4 VDD+0.5 TTL input signals V 5.5 Maximum assembly temperature (for 10 seconds maximum) Storage temperature °C 260 °C -65 150 Stresses greater those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not guaranteed. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. During overload conditions V ( IN>V DD or V IN<VSS) the voltage on pins with respect to ground (VSS) must not exceed the values defined by the Absolute Maximum Ratings. 4.2 Operating conditions Table 4.2 Symbol VDD Operating conditions Parameter Supply Voltage Supply Ripple (DC to 1 GHz) Units V Min 3.0 Typ 3.3 mV TA Ambient temperature °C IDD Supply current @ 25°C, 3.3 volts with parallel outputs loaded by 10pF mA Max 3.6 100 0 27 70 300 35/43 SBPH400-3 4.3 DC characteristics The following values apply to the analog signals TPAn, TPAn# Table 4.3 Symbol VOD DC characteristics for TPAn, TPAn# V(OFF) Parameter Differential output peak-to-peak voltage, terminated by 55Ω load Off-state common mode output voltage ZIC Common mode impedance (driver disabled) kΩ pF 20 24 ZID Differential impedance (driver disabled) kΩ pF 6 6 VARB1 Serial input differential amplitude for arbitration ’1’ detect mV 168 VARBZ Serial input differential amplitude for arbitration ’Z’ detect Serial input differential amplitude for arbitration ’0’ detect mV -89 Serial input differential amplitude (absolute value) during data transmission Speed signal threshold voltage relative to TPBIAS (TPBIAS-TPA common mode voltage), S200 mV 118 mV 139 264 Speed signalling threshold voltage relative to TPBIAS (TPBIAS-TPA common mode voltage), S400 mV 445 682 VARB0 VISWS VIT200 VIT400 Units mV Min 172 Typ mV Max 265 20 89 mV -168 - 260 The following values apply to the analog signals TPBn, TPBn# Table 4.4 Symbol VOD DC characteristics for TPBn, TPBn# Min 172 V(OFF) Parameter Units Differential output peak-to-peak voltage, terminated by mV 55Ω load Off-state common mode output voltage mV ZIC Common mode impedance (driver disabled) 20 VTH_BIAS_CON TpBias connect threshold Typ Max 265 20 kΩ pF V 1.0 24 VTH_BIAS_DIS ICM100 TpBias disconnect threshold Common mode output current, speed signalling off or speed signal = S100 V mA -0.81 0.6 0.44 ICM200 ICM400 Common mode output current, speed signal = S200 Common mode output current, speed signal = S400 mA mA -2.53 -8.10 -4.84 -12.4 VARB1 Serial input differential amplitude for arbitration ’1’ detect Serial input differential amplitude for arbitration ’Z’ detect mV 168 mV -89 VARBZ 36/43 89 SBPH400-3 Table 4.4 DC characteristics for TPBn, TPBn# (continued) Symbol Parameter VARB0 Serial input differential amplitude for arbitration ’0’ detect Units mV VISWS Serial input differential amplitude (absolute value) during data transmission mV Min Typ Max -168 118 - 260 The following values apply to the appropriate device pins in each case Table 4.5 DC characteristics Symbol VOH Parameter High level output voltage (IOH = -4 mA) VOHD High level output voltage (IOH = -9 mA, CTL[0:1], D[0:7], SCLK and LKON outputs) Low level output voltage (IOL= 4 mA) VOL Units V Min 2.8 V VDD-0.4 Typ Max V 0.4 Low level output voltage (IOL= 9 mA, CTL[0:1], D[0:7], SCLK and LKON outputs) High level input voltage V 0.4 VIL II Low level input voltage Input current for CMC, LREQ, LPS, PC[0:2], RESET#, ISO, PWRDWN, EXTCLK inputs V µA -10.0 0.7 +10.0 IPU IPD Input current for TDI, TMS, TRST# inputs Input current for TESTMODE, BISTRUN, TCK inputs OFF-state output current, CTL[0:1], D[0:7], LKON, TDO µA µA -125 +25 - 25 +125 mA -10.0 +10.0 VOLD VIH IOZ V 2.6 VLIT_ISO+ Positive input threshold voltage on LPS input (VDD=3.3V) V VLIT_ISO- Negative input threshold voltage on LPS input (VDD=3.3V) V 1.0 VIT_ISO+ Positive input thresholds voltage, CTL[0:1], D[0:7], LREQ inputs Negative input thresholds voltage, CTL[0:1], D[0:7], LREQ inputs V VDD/2 +0.3 VDD/2 -0.8 VCPS Threshold input voltage on CPS input as applied via an external 400 K Ohm resistor V 5.0 6.25 7.5 VO TPBIAS output voltage V 1.665 1.85 2.015 VIT_ISO- V 1.8 VDD/2 +0.8 VDD/2 -0.3 37/43 SBPH400-3 5 AC characteristics Table 5.1 Symbol AC characteristics (analog interfaces) Parameter Transmit jitter (TPA, TPB) Transmit Skew between TPA and TPB tr Transmit rise time 10% to 90% tf Transmit fall time 10% to 90% Figure 5.1 Measured Condition Unit ns Min Typ Max 0.15 ns Rl = 56Ω, Cl = 10pF Rl = 56Ω, Cl = 10pF 0.10 ns 0.5 1.2 ns 0.5 1.2 Digital interface timing SCLK SCLK tpsu tlsu tph tlh D, CTL, LREQ D, CTL Link device to SBPH400 device timing SBPH400 to Link device timing (NB SCLK runs from SBPH400 to link device) SCLK td1 td2 CTL DATA LPS Link device to SBPH400 timing at the link (Note: SCLK runs from the SBPH to the link device) 38/43 td3 SBPH400-3 Table 5.2 AC characteristics (digital interfaces) Symbol Parameter tpsu D, CTL, LREQ input setup to SCLK output Measured Condition Unit 50% to 50% ns Min 6 Typ Max tph tlsu D, CTL, LREQ hold from SCLK output 50% to 50% D, CTL output setup to SCLK 50% to 50% ns ns 0 6.5 tlh D, CTL output hold from SCLK 50% to 50% ns 0.5 td1 Delay time, SCLK input high to initial instances of D, CTL and LREQ outputs valid 50% to 50% ns 1 10 td2 Delay time, SCLK input high to subsequent instances of D, CTL and LREQ outputs valid 50% to 50% ns 1 10 td3 Delay time, SCLK input high to D, CTL 50% to 50% and LREQ outputs invalid (tri-state) ns 1 10 Table 5.3 Clock and reset parameters Symbol Parameter Measured Fextclk Dextclk External clock Frequency External clock duty cycle Jextclk External clock Jitter peak to peak FSCLK SCLK frequency 50% to 50% DSCLK SCLK duty cycle Power-on reset time, RESET# input 50% to 50% 50% to 50% Condition Unit Min Typ Max 24.576 MHz +/- 2.45 KHz 45% 55% 100 pS peak to peak Fextclk × 2 ms 45% 2 55% 39/43 SBPH400-3 6 Package Specifications The S B PH 4 00 -3 is available in a 80 pin plastic thin quad flat pack Normal operation pinout for 80 pin 12mm x 12mmTQFP AGND AVDD CPS RESET# N/C N/C DGND DGND DGND DVDD DGND DGND ISO PC2 PC1 PC0 CMC PDISABLE LPS DGND Figure 6.1 40/43 QX0/CLK24 OVDD DGND OGND 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 R1 R0 AGND AVDD AGND AVD D DGND DGND DGND DGND DGND DVDD DVDD DGND N/C QX1 TPA1 TPA1# TPB1 TPB1# TPBIAS1 AVD D TPA2 TPA2# TPB2 TPB2# TPBIAS2 DGND DGND DGND AGND TPA3 TPA3# TPB3 TPB3# TPBIAS3 80 79 78 77 76 75 74 73 72 71 70 69 68 67 66 65 64 63 62 61 60 59 58 57 56 55 54 SBPH400-3 53 52 51 50 12mm x 12mm 49 48 47 80 lead TQFP 46 45 44 43 42 41 21 22 2324 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 SCLK DATA0 DATA1 DVDD DATA2 DATA3 DATA4 DATA5 DATA6 DATA7 DGND DGND DGND DVDD CTL0 CTL1 LREQ DGND LKON LACT SBPH400-3 Figure 6.2 Data for 80 pin 12mm x 12mmTQFP BODY + 2.00 mm FOOTPRINT TOLS/LEADS DIMS A 64L 80L MAX 1.60 A1 A2 + .05 .05 MIN /.15 MAX 1.40 D + .20 14.00 D1 + .10 12.00 E E1 + .20 + .10 14.00 12.00 L e +1.5/-.10 BASIC .60 .65 b + .05 .30 .50 .22 Body: 12 x 12 x 1.60 mm 00 - 70 0 ddd ccc MAX MAX .13 .10 .08 .08 D D1 A2 A D3 N A1 48 1 A1 A2 A 33 49 32 0.10mm Seating Plane b E E1 E3 B B b E1 E 17 64 16 1 C e L1 e L 1.0 ref L K TQFP64 41/43 SBPH400-3 7 Application Circuit VD D Ca ble Po w er 10 0K 40 0K 0. 1 µ F N /C C able VDD u ser setting s VDD N /C 80 79 7 8 77 7 6 75 7 4 73 7 2 71 70 69 68 67 66 65 64 6 3 62 61 55 DGND LPS PDISABLE CMC PC0 PC1 PC2 ISO DGND DGND DVDD DGND DGND DGND N/C N/C RESET# CPS AVDD AGND 5K 250pF 1 TPA1 SCLK 60 2 TPA1# D ATA 0 59 3 TPB1 D ATA 1 58 4 TPB1# D VD D 57 5 TPBIAS1 D ATA 2 56 6 AV DD D ATA 3 55 7 TPA2 D ATA 4 54 8 TPA2# D ATA 5 53 9 TPB2 D ATA 6 52 F or TPA 2/A2 *, TP B2 /B 2*, T PB IA S2, 10 TPB2# D ATA 7 51 T PA 3 /A 3* , TP B 3/B 3* a nd T PB IA S3 c om po nent con ne ctio ns are the sam e as 11 TPBIAS 2 D GN D 50 12 DG ND D GN D 49 13 DG ND D GN D 48 14 DGND D VD D 47 15 AGND CTL0 46 Cable 55 55 3 00nF - 1µ F VD D G ro und T P A 1/A 1 *, TP B1 /B 1* and TP B IA S 1 . SBPH400-3 TPA3 CTL1 45 17 TPA3 LREQ 44 18 TPB3 D GN D 43 19 TPB3# LKON 42 20 TPBIAS 3 LACT 41 37 38 39 VD D DGND 36 OVDD 35 OGND N/C 34 QX1 33 DGND VDD 32 DVDD 31 DVDD 30 DGND 29 DGND 28 DGND 27 DGND 26 DGND 25 AVDD 24 AGND 23 AVDD R0 3.0K +/- 1% 22 AGND R1 21 QX0/CLK2 4 16 VDD LIN K IN T E R FA C E (* ) 55 40 VD D N /C V DD N C* * E xternal 24.576 M H z Cr ystal O R E xternal oscill ator option (* ) Iso lation circu it use d if ISO pin enab le (* *) A ll N /C (no n connec ted ) p ins, B UT N O T N C ** (p in 3 6) may b e con nec ted to e ither G N D o r V D D Note: 42/43 Isolation components when using an isolated PHY-Link interface not shown; Notes Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsibility for the consequences of use of such information nor for 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 or patent rights of SGS-THOMSON Microelectronics. Specifications mentioned in this publication are subject to change without notice. This publication supercedes and replaces all information previously supplied. SGS-THOMSON Microelectronics products are not authorized for use as critical components in life support devices or systems without the express written approval of SGS-THOMSON Microelectronics. 1998 SGS-THOMSON Microelectronics - All rights reserved. GLINTTM is a Trademark of BULL S.A. This circuit uses patents licenced by BULL S.A. SGS-THOMSON Microelectronics Group of Companies Australia - Brazil - Canada - China - France - Germany - Hong Kong - Italy - Japan - Korea - Malaysia - Malta - Morocco - The Netherlands Singapore - Spain - Sweden - Switzerland - Taiwan - Thailand - United Kingdom - U.S.A. 43/43 3