DP83848K PHYTER® Mini LS Industrial Temperature Single Port 10/100 Ethernet Transceiver General Description Features The DP83848K addresses the quality, reliability and small • Low-power 3.3V, 0.18µm CMOS technology form factor required for space sensitive applications in • Auto-MDIX for 10/100 Mb/s embedded systems operating in the industrial temperature • Energy Detection Mode range. • 3.3V MAC Interface The DP83848K offers performance far exceeding the IEEE specifications, with superior interoperability and • RMII Rev. 1.2 Interface (configurable) industry leading performance beyond 137m of Cat-V • MII Interface cable. The DP83848K also offers Auto-MDIX to remove • MII serial management interface (MDC and MDIO) cabling complications. DP83848K has superior ESD protection, greater than 4KV Human Body Model, providing • IEEE 802.3u Auto-Negotiation and Parallel Detection extremely high reliability and robust operation, ensuring a • IEEE 802.3u ENDEC, 10BASE-T transceivers and filters high level performance in all applications. • IEEE 802.3u PCS, 100BASE-TX transceivers and filters DP83848K offers two flexible LED indicators - one for Link • Integrated ANSI X3.263 compliant TP-PMD physical suband the other for Speed. In addition, both MII and RMII are layer with adaptive equalization and Baseline Wander supported ensuring ease and flexibility of design. compensation The DP83848K is offered in a tiny 6mm x 6mm LLP 40-pin • Error-free Operation beyond 137 meters package and is ideal for industrial controls, building/factory automation, transportation, test equipment and wireless • ESD protection - greater than 4KV Human body model • Configurable LED for link and activity base stations. • Single register access for complete PHY status Applications • 10/100 Mb/s packet BIST (Built in Self Test) • Peripheral devices • 40 pin LLP package (6mm) x (6mm) x (0.8mm) • Mobile devices • Factory and building automation • Basestations MII/RMII 10/100 Ethernet Transceiver Clock Source RJ-45 DP83848K Magnetics MPU/CPU Media Access Controlleroler System Diagram 10BASE-T or 100BASE-TX Status LED/s Typical Ethernet Application PHYTER® is a registered trademark of National Semiconductor Corporation. © 2008 National Semiconductor Corporation www.national.com DP83848K PHYTER® Mini LS Industrial Temperature Single Port 10/100 Ethernet Transceiver May 2008 DP83848K RX_CLK RXD[3:0] RX_DV RX_ER COL MDC MDIO TX_EN TX_CLK TXD[3:0] SERIAL MANAGEMENT CRS/CRS_DV MII/RMII MII/RMII INTERFACE TX_DATA RX_CLK TX_CLK RX_DATA MII Registers 10BASE-T & Auto-Negotiation State Machine Transmit Block 10BASE-T & Receive Block Clock Generation ADC DAC Auto-MDIX TD± RD± LED Driver REFERENCE CLOCK Figure 1. DP83848K Functional Block Diagram www.national.com 2 LEDS 1.0 Pin Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 1.1 Serial Management Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9 1.2 MAC Data Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9 1.3 Clock Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10 1.4 LED Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 1.5 Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 1.6 Strap Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 1.7 10 Mb/s and 100 Mb/s PMD Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13 1.8 Special Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13 1.9 Power Supply Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13 1.10 Package Pin Assignments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14 2.0 Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 2.1 Auto-Negotiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15 2.1.1 2.1.2 2.1.3 2.1.4 2.1.5 Auto-Negotiation Pin Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Auto-Negotiation Register Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Auto-Negotiation Parallel Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Auto-Negotiation Restart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Auto-Negotiation Complete Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 15 16 16 16 2.2 Auto-MDIX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16 2.3 PHY Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17 2.3.1 MII Isolate Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 2.4 LED Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18 2.4.1 LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 2.4.2 LED Direct Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 2.5 Half Duplex vs. Full Duplex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19 2.6 Internal Loopback . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19 2.7 BIST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19 3.0 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 3.1 MII Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20 3.1.1 Nibble-wide MII Data Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 3.1.2 Collision Detect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 3.1.3 Carrier Sense . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 3.2 Reduced MII Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20 3.3 802.3u MII Serial Management Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21 3.3.1 Serial Management Register Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 3.3.2 Serial Management Access Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 3.3.3 Serial Management Preamble Suppression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 4.0 Architecture. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 4.1 100BASE-TX TRANSMITTER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23 4.1.1 4.1.2 4.1.3 4.1.4 Code-group Encoding and Injection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Scrambler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . NRZ to NRZI Encoder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Binary to MLT-3 Convertor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 25 25 25 4.2 100BASE-TX RECEIVER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25 4.2.1 Analog Front End . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.2 Digital Signal Processor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.2.1 Digital Adaptive Equalization and Gain Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.2.2 Base Line Wander Compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.3 Signal Detect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.4 MLT-3 to NRZI Decoder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.5 NRZI to NRZ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.6 Serial to Parallel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.7 Descrambler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.8 Code-group Alignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.9 4B/5B Decoder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 25 25 27 28 28 28 28 28 29 29 29 www.national.com DP83848K Table of Contents DP83848K 4.2.10 100BASE-TX Link Integrity Monitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 4.2.11 Bad SSD Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 4.3 10BASE-T TRANSCEIVER MODULE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29 4.3.1 Operational Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.2 Smart Squelch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.3 Collision Detection and SQE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.4 Carrier Sense . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.5 Normal Link Pulse Detection/Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.6 Jabber Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.7 Automatic Link Polarity Detection and Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.8 Transmit and Receive Filtering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.9 Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.10 Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 30 30 30 30 31 31 31 31 31 5.0 Design Guidelines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 5.1 5.2 5.3 5.4 5.5 5.6 TPI Network Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32 ESD Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33 Clock In (X1) ReCommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33 Power Feedback Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35 Power Down . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35 Energy Detect Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35 6.0 Reset Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 6.1 Hardware Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35 6.2 Software Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35 7.0 Register Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 7.1 Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39 7.1.1 7.1.2 7.1.3 7.1.4 7.1.5 7.1.6 7.1.7 7.1.8 7.1.9 Basic Mode Control Register (BMCR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Basic Mode Status Register (BMSR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PHY Identifier Register #1 (PHYIDR1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PHY Identifier Register #2 (PHYIDR2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Auto-Negotiation Advertisement Register (ANAR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Auto-Negotiation Link Partner Ability Register (ANLPAR) (BASE Page) . . . . . . . . . . . . . . . . Auto-Negotiation Link Partner Ability Register (ANLPAR) (Next Page) . . . . . . . . . . . . . . . . . Auto-Negotiate Expansion Register (ANER) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Auto-Negotiation Next Page Transmit Register (ANNPTR) . . . . . . . . . . . . . . . . . . . . . . . . . . 40 42 43 43 43 45 46 46 47 7.2 Extended Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48 7.2.1 PHY Status Register (PHYSTS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.2.2 False Carrier Sense Counter Register (FCSCR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.2.3 Receiver Error Counter Register (RECR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.2.4 100 Mb/s PCS Configuration and Status Register (PCSR) . . . . . . . . . . . . . . . . . . . . . . . . . . 7.2.5 RMII and Bypass Register (RBR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.2.6 LED Direct Control Register (LEDCR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.2.7 PHY Control Register (PHYCR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.2.8 10Base-T Status/Control Register (10BTSCR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.2.9 CD Test and BIST Extensions Register (CDCTRL1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.2.10 Energy Detect Control (EDCR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 50 50 51 52 53 54 56 57 58 8.0 Electrical Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 8.1 DC Specs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59 8.2 AC Specs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61 8.2.1 Power Up Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.2.2 Reset Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.2.3 MII Serial Management Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.2.4 100 Mb/s MII Transmit Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.2.5 100 Mb/s MII Receive Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.2.6 100BASE-TX Transmit Packet Latency Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.2.7 100BASE-TX Transmit Packet Deassertion Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.2.8 100BASE-TX Transmit Timing (tR/F & Jitter) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.2.9 100BASE-TX Receive Packet Latency Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.2.10 100BASE-TX Receive Packet Deassertion Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.2.11 10 Mb/s MII Transmit Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.2.12 10 Mb/s MII Receive Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . www.national.com 4 61 62 63 63 64 64 65 66 67 67 68 68 10BASE-T Transmit Timing (Start of Packet) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10BASE-T Transmit Timing (End of Packet) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10BASE-T Receive Timing (Start of Packet) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10BASE-T Receive Timing (End of Packet) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Mb/s Heartbeat Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Mb/s Jabber Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10BASE-T Normal Link Pulse Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Auto-Negotiation Fast Link Pulse (FLP) Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100BASE-TX Signal Detect Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 Mb/s Internal Loopback Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Mb/s Internal Loopback Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RMII Transmit Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RMII Receive Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Isolation Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 Mb/s X1 to TX_CLK Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 69 69 70 70 71 71 72 72 73 73 74 75 76 77 77 www.national.com DP83848K 8.2.13 8.2.14 8.2.15 8.2.16 8.2.17 8.2.18 8.2.19 8.2.20 8.2.21 8.2.22 8.2.23 8.2.24 8.2.25 8.2.26 8.2.27 DP83848K List of Figures Figure 1. DP83848K Functional Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Figure 2. PHYAD Strapping Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Figure 3. AN Strapping and LED Loading Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Figure 4. Typical MDC/MDIO Read Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Figure 5. Typical MDC/MDIO Write Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Figure 6. 100BASE-TX Transmit Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Figure 7. 100BASE-TX Receive Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Figure 8. EIA/TIA Attenuation vs. Frequency for 0, 50, 100, 130 & 150 meters of CAT 5 cable . . . . . 27 Figure 9. 100BASE-TX BLW Event . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Figure 10. 10BASE-T Twisted Pair Smart Squelch Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Figure 11. 10/100 Mb/s Twisted Pair Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Figure 12. Crystal Oscillator Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Figure 13. Power Feedback Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 www.national.com 6 Table 1. Auto-Negotiation Modes in DP83848K . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Table 2. PHY Address Mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Table 3. LED Mode Select for DP83848K . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Table 4. Supported packet sizes at +/-50ppm +/-100ppm for each clock . . . . . . . . . . . . . . . . . . . . . . 21 Table 5. Typical MDIO Frame Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Table 6. 4B5B Code-Group Encoding/Decoding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Table 7. 25 MHz Oscillator Specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Table 8. 50 MHz Oscillator Specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Table 9. 25 MHz Crystal Specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Table 10. Register Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Table 11. Register Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Table 12. Basic Mode Control Register (BMCR), address 0x00 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Table 13. Basic Mode Status Register (BMSR), address 0x01 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 Table 14. PHY Identifier Register #1 (PHYIDR1), address 0x02 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Table 15. PHY Identifier Register #2 (PHYIDR2), address 0x03 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Table 16. Negotiation Advertisement Register (ANAR), address 0x04 . . . . . . . . . . . . . . . . . . . . . . . . 43 Table 17. Auto-Negotiation Link Partner Ability Register (ANLPAR) (BASE Page), address 0x05 . . . 45 Table 18. Auto-Negotiation Link Partner Ability Register (ANLPAR) (Next Page), address 0x05 . . . . 46 Table 19. Auto-Negotiate Expansion Register (ANER), address 0x06 . . . . . . . . . . . . . . . . . . . . . . . . 46 Table 20. Auto-Negotiation Next Page Transmit Register (ANNPTR), address 0x07 . . . . . . . . . . . . . 47 Table 21. PHY Status Register (PHYSTS), address 0x10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 Table 22. False Carrier Sense Counter Register (FCSCR), address 0x14 . . . . . . . . . . . . . . . . . . . . . 50 Table 23. Receiver Error Counter Register (RECR), address 0x15 . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 Table 24. 100 Mb/s PCS Configuration and Status Register (PCSR), address 0x16 . . . . . . . . . . . . . 51 Table 25. RMII and Bypass Register (RBR), addresses 0x17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 Table 26. LED Direct Control Register (LEDCR), address 0x18 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 Table 27. PHY Control Register (PHYCR), address 0x19 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 Table 28. 10Base-T Status/Control Register (10BTSCR), address 0x1A . . . . . . . . . . . . . . . . . . . . . . 56 Table 29. CD Test and BIST Extensions Register (CDCTRL1), address 0x1B . . . . . . . . . . . . . . . . . . 57 Table 30. Energy Detect Control (EDCR), address 0x1D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 7 www.national.com DP83848K List of Tables DP83848K Pin Layout for DP83848K RX_CLK 31 RX_DV/MII_MODE 32 CRS/CRS_DV/LED_CFG 33 RX_ER/MDIX_EN 34 COL/PHYAD0 35 RXD_0/PHYAD1 36 RXD_1/PHYAD2 37 RXD_2/PHYAD3 38 RXD_3/PHYAD4 39 IOGND 40 IOVDD33 1 30 PFBIN2 TX_CLK 2 29 DGND TX_EN 3 28 X1 TXD_0 4 27 X2 TXD_1 5 TXD_2 6 TXD_3 7 24 MDIO RESERVED 8 23 RESET_N RESERVED 9 RESERVED 10 26 IOVDD33 DP83848K 25 MDC 22 LED_LINK/AN0 DAP 21 LED_SPEED/AN1 20 RBIAS 19 PFBOUT 18 AVDD33 17 AGND 16 PFBIN1 15 TD + 14 TD - 13 AGND 12 RD + 11 RD - Note: Die Attached Pad (DAP) provides thermal dissipation, connection to GND plane recommended. Top View Order Number DP83848K NS Package Number NSQAU040 www.national.com 8 The DP83848K pins are classified into the following interface categories (each interface is described in the sections that follow): Note: Strapping pin option. Please see Section 1.6 for strap definitions. — — — — — — — — — Type: I Type: O Type: I/O Type: PD,PU Type: S All DP83848K signal pins are I/O cells regardless of the particular use. The definitions below define the functionality of the I/O cells for each pin. Serial Management Interface MAC Data Interface Clock Interface LED Interface Reset Strap Options 10/100 Mb/s PMD Interface Special Connect Pins Power and Ground pins Input Output Input/Output Internal Pulldown/Pullup Strapping Pin (All strap pins have weak internal pull-ups or pull-downs. If the default strap value is needed to be changed then an external 2.2 kΩ resistor should be used. Please see Section 1.6 for details.) 1.1 SERIAL MANAGEMENT INTERFACE Signal Name Type Pin # Description MDC I 25 MANAGEMENT DATA CLOCK: Synchronous clock to the MDIO management data input/output serial interface which may be asynchronous to transmit and receive clocks. The maximum clock rate is 25 MHz with no minimum clock rate. MDIO I/O 24 MANAGEMENT DATA I/O: Bi-directional management instruction/data signal that may be sourced by the station management entity or the PHY. This pin requires a 1.5 kΩ pullup resistor. Type Pin # Description O 2 MII TRANSMIT CLOCK: 25 MHz Transmit clock output in 100 Mb/s mode or 2.5 MHz in 10 Mb/s mode derived from the 25 MHz reference clock. 1.2 MAC DATA INTERFACE Signal Name TX_CLK Unused in RMII mode. The device uses the X1 reference clock input as the 50 MHz reference for both transmit and receive. TX_EN I, PD 3 MII TRANSMIT ENABLE: Active high input indicates the presence of valid data inputs on TXD[3:0]. RMII TRANSMIT ENABLE: Active high input indicates the presence of valid data on TXD[1:0]. TXD_0 I 4 TXD_1 5 TXD_2 6 TXD_3 RX_CLK I, PD 7 O 31 MII TRANSMIT DATA: Transmit data MII input pins, TXD[3:0], that accept data synchronous to the TX_CLK (2.5 MHz in 10 Mb/s mode or 25 MHz in 100 Mb/s mode). RMII TRANSMIT DATA: Transmit data RMII input pins, TXD[1:0], that accept data synchronous to the 50 MHz reference clock. MII RECEIVE CLOCK: Provides the 25 MHz recovered receive clocks for 100 Mb/s mode and 2.5 MHz for 10 Mb/s mode. Unused in RMII mode. The device uses the X1 reference clock input as the 50 MHz reference for both transmit and receive. RX_DV O, PD 32 MII RECEIVE DATA VALID: Asserted high to indicate that valid data is present on the corresponding RXD[3:0]. RMII Synchronous Receive Data Valid: This signal provides the RMII Receive Data Valid indication independent of Carrier Sense. 9 www.national.com DP83848K 1.0 Pin Descriptions DP83848K Signal Name RX_ER Type Pin # Description S, O, PU 34 MII RECEIVE ERROR: Asserted high synchronously to RX_CLK to indicate that an invalid symbol has been detected within a received packet in 100 Mb/s mode. RMII RECEIVE ERROR: Assert high synchronously to X1 whenever it detects a media error and RX_DV is asserted in 100 Mb/s mode. This pin is not required to be used by a MAC, in either MII or RMII mode, since the Phy is required to corrupt data on a receive error. RXD_0 S, O, PD 36 MII RECEIVE DATA: Nibble wide receive data signals driven synchronously to the RX_CLK, 25 MHz for 100 Mb/s mode, 2.5 MHz for 10 Mb/s mode). RXD[3:0] signals contain valid data when RX_DV is asserted. RXD_1 37 RXD_2 38 RXD_3 39 RMII RECEIVE DATA: 2-bits receive data signals, RXD[1:0], driven synchronously to the X1 clock, 50 MHz. 33 MII CARRIER SENSE: Asserted high to indicate the receive medium is non-idle. CRS/CRS_DV S, O, PU RMII CARRIER SENSE/RECEIVE DATA VALID: This signal combines the RMII Carrier and Receive Data Valid indications. For a detailed description of this signal, see the RMII Specification. COL S, O, PU 35 MII COLLISION DETECT: Asserted high to indicate detection of a collision condition (simultaneous transmit and receive activity) in 10 Mb/s and 100 Mb/s Half Duplex Modes. While in 10BASE-T Half Duplex mode with heartbeat enabled this pin is also asserted for a duration of approximately 1µs at the end of transmission to indicate heartbeat (SQE test). In Full Duplex Mode, for 10 Mb/s or 100 Mb/s operation, this signal is always logic 0. There is no heartbeat function during 10 Mb/s full duplex operation. RMII COLLISION DETECT: Per the RMII Specification, no COL signal is required. The MAC will recover CRS from the CRS_DV signal and use that along with its TX_EN signal to determine collision. 1.3 CLOCK INTERFACE Signal Name X1 Type Pin # Description I 28 CRYSTAL/OSCILLATOR INPUT: This pin is the primary clock reference input for the DP83848K and must be connected to a 25 MHz 0.005% (+50 ppm) clock source. The DP83848K supports either an external crystal resonator connected across pins X1 and X2, or an external CMOS-level oscillator source connected to pin X1 only. RMII REFERENCE CLOCK: This pin is the primary clock reference input for the RMII mode and must be connected to a 50 MHz 0.005% (+50 ppm) CMOS-level oscillator source. X2 www.national.com O 27 CRYSTAL OUTPUT: This pin is the primary clock reference output to connect to an external 25 MHz crystal resonator device. This pin must be left unconnected if an external CMOS oscillator clock source is used. 10 DP83848K 1.4 LED INTERFACE See Table 3 for LED Mode Selection. Signal Name LED_LINK Type Pin # Description S, O, PU 22 LINK LED: In Mode 1, this pin indicates the status of the LINK. The LED will be ON when Link is good. LINK/ACT LED: In Mode 2, this pin indicates transmit and receive activity in addition to the status of the Link. The LED will be ON when Link is good. It will blink when the transmitter or receiver is active. LED_SPEED S, O, PU 21 SPEED LED: This LED is ON when DP83848K is in 100Mb/s and OFF when DP83848K is in 10Mb/s. Functionality of this LED is independent of the mode selected. Type Pin # Description I, PU 23 RESET: Active Low input that initializes or re-initializes the DP83848K. Asserting this pin low for at least 1 µs will force a reset process to occur. All internal registers will re-initialize to their default states as specified for each bit in the Register Block section. All strap options are re-initialized as well. 1.5 RESET Signal Name RESET_N 1.6 STRAP OPTIONS DP83848K uses many functional pins as strap options. The values of these pins are sampled during reset and used to strap the device into specific modes of operation. The strap option pin assignments are defined below. The functional pin name is indicated in parentheses. Signal Name A 2.2 kΩ resistor should be used for pull-down or pull-up to change the default strap option. If the default option is required, then there is no need for external pull-up or pull down resistors. Since these pins may have alternate functions after reset is deasserted, they should not be connected directly to VCC or GND. Type Pin # Description PHYAD0 (COL) S, O, PU 35 PHYAD1 (RXD_0) S, O, PD 36 PHY ADDRESS [4:0]: The DP83848K provides five PHY address pins, the state of which are latched into the PHYCTRL register at system Hardware-Reset. PHYAD2 (RXD_1) 37 PHYAD3 (RXD_2) 38 PHYAD4 (RXD_3) 39 The DP83848K supports PHY Address strapping values 0 (<00000>) through 31 (<11111>). A PHY Address of 0 puts the part into the MII Isolate Mode. The MII isolate mode must be selected by strapping Phy Address 0; changing to Address 0 by register write will not put the Phy in the MII isolate mode. Please refer to section 2.3 for additional information. PHYAD0 pin has weak internal pull-up resistor. PHYAD[4:1] pins have weak internal pull-down resistors. 11 www.national.com DP83848K Signal Name Type Pin # Description AN0 (LED_LINK) S, O, PU 22 AN1 (LED_SPEED) S, O, PU 21 These input pins control the advertised operating mode of the device according to the following table. The value on these pins are set by connecting them to GND (0) or VCC (1) through 2.2 kΩ resistors. These pins should NEVER be connected directly to GND or VCC. The value set at this input is latched into the DP83848K at Hardware-Reset. The float/pull-down status of these pins are latched into the Basic Mode Control Register and the Auto_Negotiation Advertisement Register during Hardware-Reset. The default for DP83848K is 11 since these pins have an internal pull-up. AN1 AN0 Advertised Mode 0 0 10BASE-T, Half/Full-Duplex 0 1 100BASE-TX, Half/Full-Duplex 1 0 10BASE-T, Half-Duplex 100BASE-TX, Half-Duplex 1 1 10BASE-T, Half/Full-Duplex 100BASE-TX, Half/Full-Duplex MII_MODE (RX_DV) S, O, PD 32 MII MODE SELECT: This strapping option determines the operating mode of the MAC Data Interface. Default operation (No pullup) will enable normal MII Mode of operation. Strapping MII_MODE high will cause the device to be in RMII mode of operation. Since the pin includes an internal pull-down, the default value is 0. The following table details the configuration: MII_MODE LED_CFG (CRS/CRS_DV) S, O, PU 33 MAC Interface Mode 0 MII Mode 1 RMII Mode LED CONFIGURATION: This strapping option determines the mode of operation of the LED pins. Default is Mode 1. Mode 1 and Mode 2 can be controlled via the strap option. All modes are configurable via register access. SeeTable 3 for LED Mode Selection. MDIX_EN (RX_ER) www.national.com S, O, PU 34 MDIX ENABLE: Default is to enable MDIX. This strapping option disables Auto-MDIX. An external pull-down will disable AutoMDIX mode. 12 Signal Name TD-, TD+ Type Pin # Description I/O 14, 15 Differential common driver transmit output (PMD Output Pair). These differential outputs are automatically configured to either 10BASE-T or 100BASE-TX signaling. In Auto-MDIX mode of operation, this pair can be used as the Receive Input pair. These pins require 3.3V bias for operation. RD-, RD+ I/O 11, 12 Differential receive input (PMD Input Pair). These differential inputs are automatically configured to accept either 100BASE-TX or 10BASE-T signaling. In Auto-MDIX mode of operation, this pair can be used as the Transmit Output pair. These pins require 3.3V bias for operation. 1.8 SPECIAL CONNECTIONS Type Pin # Description RBIAS Signal Name I 20 Bias Resistor Connection. A 4.87 kΩ 1% resistor should be connected from RBIAS to GND. PFBOUT O 19 Power Feedback Output. Parallel caps, 10µ F (Tantalum preferred) and 0.1µF, should be placed close to the PFBOUT. Connect this pin to PFBIN1 (pin 16) and PFBIN2 (pin 30). See Section 5.4 for proper placement pin. PFBIN1 I 16 Power Feedback Input. These pins are fed with power from PFBOUT pin. A small capacitor of 0.1µF should be connected close to each pin. PFBIN2 30 Note: Do not supply power to these pins other than from PFBOUT. RESERVED I/O 8,9,10 RESERVED: These pins must be left unconnected. 1.9 POWER SUPPLY PINS Signal Name IOVDD33 IOGND Pin # 1, 26 Description I/O 3.3V Supply 40 I/O Ground DGND 29 Digital Ground AVDD33 18 Analog 3.3V Supply AGND 13, 17 Analog Ground 13 www.national.com DP83848K 1.7 10 MB/S AND 100 MB/S PMD INTERFACE DP83848K 1.10 PACKAGE PIN ASSIGNMENTS NSQAU040 Pin Name Pin # (DP83848K) 1 IO_VDD 2 TX_CLK 3 TX_EN 4 TXD_0 5 TXD_1 6 TXD_2 7 TXD_3 8 RESERVED 9 RESERVED 10 RESERVED 11 RD- 12 RD+ 13 AGND 14 TD - 15 TD + 16 PFBIN1 17 AGND 18 AVDD33 19 PFBOUT 20 RBIAS 21 LED_SPEED/AN1 22 LED_LINK/AN0 23 RESET_N 24 MDIO 25 MDC 26 IOVDD33 27 X2 28 X1 29 DGND 30 PFBIN2 31 RX_CLK 32 RX_DV/MII_MODE 33 CRS/CRS_DV/LED_CFG 34 RX_ER/MDIX_EN 35 COL/PHYAD0 36 RXD_0/PHYAD1 37 RXD_1/PHYAD2 38 RXD_2/PHYAD3 39 RXD_3/PHYAD4 40 IOGND www.national.com 14 This section includes information on the various configuration options available with the DP83848K. The configuration options described below include: — — — — — — Auto-Negotiation PHY Address and LED Half Duplex vs. Full Duplex Isolate mode Loopback mode BIST 2.1.2 Auto-Negotiation Register Control When Auto-Negotiation is enabled, the DP83848K transmits the abilities programmed into the Auto-Negotiation Advertisement register (ANAR) at address 04h via FLP Bursts. Any combination of 10 Mb/s, 100 Mb/s, HalfDuplex, and Full Duplex modes may be selected. Auto-Negotiation Priority Resolution: — (1) 100BASE-TX Full Duplex (Highest Priority) — (2) 100BASE-TX Half Duplex — (3) 10BASE-T Full Duplex — (4) 10BASE-T Half Duplex (Lowest Priority) 2.1 AUTO-NEGOTIATION The Basic Mode Control Register (BMCR) at address 00h The Auto-Negotiation function provides a mechanism for provides control for enabling, disabling, and restarting the exchanging configuration information between two ends of Auto-Negotiation process. When Auto-Negotiation is disa link segment and automatically selecting the highest per- abled, the Speed Selection bit in the BMCR controls formance mode of operation supported by both devices. switching between 10 Mb/s or 100 Mb/s operation, and the Fast Link Pulse (FLP) Bursts provide the signalling used to Duplex Mode bit controls switching between full duplex communicate Auto-Negotiation abilities between two operation and half duplex operation. The Speed Selection devices at each end of a link segment. For further detail and Duplex Mode bits have no effect on the mode of operregarding Auto-Negotiation, refer to Clause 28 of the IEEE ation when the Auto-Negotiation Enable bit is set. 802.3u specification. The DP83848K supports four differ- The Link Speed can be examined through the PHY Status ent Ethernet protocols (10 Mb/s Half Duplex, 10 Mb/s Full Register (PHYSTS) at address 10h after a Link is Duplex, 100 Mb/s Half Duplex, and 100 Mb/s Full Duplex), achieved. so the inclusion of Auto-Negotiation ensures that the highThe Basic Mode Status Register (BMSR) indicates the set est performance protocol will be selected based on the of available abilities for technology types, Auto-Negotiation advertised ability of the Link Partner. In DP83848K, the Auto-Negotiation function can be controlled either by inter- ability, and Extended Register Capability. These bits are permanently set to indicate the full functionality of the nal register access or by the use of AN0 and AN1 pins. DP83848K (only the 100BASE-T4 bit is not set since the DP83848K does not support that function). 2.1.1 Auto-Negotiation Pin Control The state of AN0 and AN1 pins determine the specific mode advertised by the device as given in Table 1.. The state of AN0 and AN1 pins, upon power-up/reset, determines the state of bits [8:5] of the ANAR register. The Auto-Negotiation function selected at power-up or reset can be changed at any time by writing to the Basic Mode Control Register (BMCR) at address 0x00h Table 1. Auto-Negotiation Modes in DP83848K AN1 AN0 Advertised Mode 0 0 10BASE-T, Half/Full-Duplex 0 1 100BASE-TX, Half/Full-Duplex 1 0 10BASE-T, Half-Duplex 100BASE-TX, Half-Duplex 1 1 10BASE-T, Half/Full-Duplex 100BASE-TX, Half/Full-Duplex The BMSR also provides status on: — Completion of Auto-Negotiation — Occurrence of a remote fault as advertised by the Link Partner — Establishment of a valid link — Support for Management Frame Preamble suppression The Auto-Negotiation Advertisement Register (ANAR) indicates the Auto-Negotiation abilities to be advertised by the DP83848K. All available abilities are transmitted by default, but any ability can be suppressed by writing to the ANAR. Updating the ANAR to suppress an ability is one way for a management agent to change (restrict) the technology that is used. The Auto-Negotiation Link Partner Ability Register (ANLPAR) at address 05h is used to receive the base link code word as well as all next page code words during the negotiation. Furthermore, the ANLPAR will be updated to either 0081h or 0021h for parallel detection to either 100 Mb/s or 10 Mb/s respectively. The Auto-Negotiation Expansion Register (ANER) indicates additional Auto-Negotiation status. The ANER provides status on: — — — — Occurrence of a Parallel Detect Fault Next Page function support by the Link Partner Next page support function by DP83848K Reception of the current page that is exchanged by AutoNegotiation — Auto-Negotiation support by the Link Partner 15 www.national.com DP83848K 2.0 Configuration DP83848K 2.1.3 Auto-Negotiation Parallel Detection 2.1.5 Auto-Negotiation Complete Time The DP83848K supports the Parallel Detection function as defined in the IEEE 802.3u specification. Parallel Detection requires both the 10 Mb/s and 100 Mb/s receivers to monitor the receive signal and report link status to the Auto-Negotiation function. Auto-Negotiation uses this information to configure the correct technology in the event that the Link Partner does not support Auto-Negotiation but is transmitting link signals that the 100BASE-TX or 10BASE-T PMAs recognize as valid link signals. Parallel detection and Auto-Negotiation take approximately 2-3 seconds to complete. In addition, Auto-Negotiation with next page should take approximately 2-3 seconds to complete, depending on the number of next pages sent. Refer to Clause 28 of the IEEE 802.3u standard for a full description of the individual timers related to Auto-Negotiation. If the DP83848K completes Auto-Negotiation as a result of Parallel Detection, bit 5 or bit 7 within the ANLPAR register will be set to reflect the mode of operation present in the Link Partner. Note that bits 4:0 of the ANLPAR will also be set to 00001 based on a successful parallel detection to indicate a valid 802.3 selector field. Software may determine that negotiation completed via Parallel Detection by reading a zero in the Link Partner Auto-Negotiation Able bit once the Auto-Negotiation Complete bit is set. If configured for parallel detect mode and any condition other than a single good link occurs then the parallel detect fault bit will be set. 2.2 AUTO-MDIX When enabled, this function utilizes Auto-Negotiation to determine the proper configuration for transmission and reception of data and subsequently selects the appropriate MDI pair for MDI/MDIX operation. The function uses a random seed to control switching of the crossover circuitry. This implementation complies with the corresponding IEEE 802.3 Auto-Negotiation and Crossover Specifications. Auto-MDIX is enabled by default and can be configured via strap or via PHYCR (0x19h) register, bits [15:14]. Neither Auto-Negotiation nor Auto-MDIX is required to be enabled in forcing crossover of the MDI pairs. Forced crossover can be achieved through the FORCE_MDIX bit, bit 14 of PHYCR (0x19h) register. 2.1.4 Auto-Negotiation Restart Once Auto-Negotiation has completed, it may be restarted at any time by setting bit 9 (Restart Auto-Negotiation) of the BMCR to one. If the mode configured by a successful Auto-Negotiation loses a valid link, then the Auto-Negotiation process will resume and attempt to determine the configuration for the link. This function ensures that a valid configuration is maintained if the cable becomes disconnected. Note: Auto-MDIX will not work in a forced mode of operation. A renegotiation request from any entity, such as a management agent, will cause the DP83848K to halt any transmit data and link pulse activity until the break_link_timer expires (~1500 ms). Consequently, the Link Partner will go into link fail and normal Auto-Negotiation resumes. The DP83848K will resume Auto-Negotiation after the break_link_timer has expired by issuing FLP (Fast Link Pulse) bursts. www.national.com 16 The 5 PHY address inputs pins are shared with the RXD[3:0] pins and COL pin as shown below. Refer to Figure 2 for an example of a PHYAD connection to external components. In this example, the PHYAD strapping results in address 00011 (03h). Table 2. PHY Address Mapping Pin # PHYAD Function Since the PHYAD[0] pin has weak internal pull-up resistor and PHYAD[4:1] pins have weak internal pull-down resistors, the default setting for the PHY address is 00001 (01h). RXD Function 35 PHYAD0 COL 36 PHYAD1 RXD_0 2.3.1 MII Isolate Mode 37 PHYAD2 RXD_1 38 PHYAD3 RXD_2 39 PHYAD4 RXD_3 The DP83848K can be put into MII Isolate mode by writing to bit 10 of the BMCR register or by strapping in Physical Address 0. It should be noted that selecting Physical Address 0 via an MDIO write to PHYCR will not put the device in the MII isolate mode. The DP83848K can be set to respond to any of 32 possible PHY addresses via strap pins. The information is latched into the PHYCR register (address 19h, bits [4:0]) at device power-up and hardware reset. The PHY Address pins are shared with the RXD and COL pins. Each DP83848K or port sharing an MDIO bus in a system must have a unique physical address. The DP83848K supports PHY Address strapping values 0 (<00000>) through 31 (<11111>). Strapping PHY Address 0 puts the part into Isolate Mode. It should also be noted that selecting PHY Address 0 via an MDIO write to PHYCR will not put the device in Isolate Mode. See Section 2.3.1 for more information. While in Isolate mode, the PMD output pair will not transmit packet data but will continue to source 100BASE-TX scrambled idles or 10BASE-T normal link pulses. COL 2.2kΩ PHYAD0 = 1 PHYAD1 = 1 RXD_1 RXD_0 The DP83848K can Auto-Negotiate or parallel detect to a specific technology depending on the receive signal at the PMD input pair. A valid link can be established for the receiver even when the DP83848K is in Isolate mode. PHYAD2 = 0 RXD_2 PHYAD3 = 0 PHYAD4 = 0 RXD_3 For further detail relating to the latch-in timing requirements of the PHY Address pins, as well as the other hardware configuration pins, refer to the Reset summary in Section 6.0. When in the MII isolate mode, the DP83848K does not respond to packet data present at TXD[3:0], TX_EN inputs and presents a high impedance on the TX_CLK, RX_CLK, RX_DV, RX_ER, RXD[3:0], COL, and CRS outputs. When in Isolate mode, the DP83848K will continue to respond to all management transactions. VCC Figure 2. PHYAD Strapping Example 17 www.national.com DP83848K 2.3 PHY ADDRESS . See Table 3. for LED Mode selection of DP83848K. Table 3. LED Mode Select for DP83848K 1 2 0 LED_SPEED ON for Good Link ON in 100Mb/s OFF for No Link OFF in 10Mb/s ON for Good Link ON in 100Mb/s 275Ω BLINK for Activity OFF in 10Mb/s The LED_LINK pin in Mode 1 indicates the link status of the port. In 100BASE-T mode, link is established as a result of input receive amplitude compliant with the TPPMD specifications which will result in internal generation of signal detect. A 10 Mb/s Link is established as a result of the reception of at least seven consecutive normal Link Pulses or the reception of a valid 10BASE-T packet. This will cause the assertion of LED_LINK. LED_LINK will deassert in accordance with the Link Loss Timer as specified in the IEEE 802.3 specification. Figure 3. AN Strapping and LED Loading Example 2.4.2 LED Direct Control The DP83848K provides another option to directly control the LED outputs through the LED Direct Control Register (LEDCR), address 18h. The register does not provide read access to the LED. The LED_LINK pin in Mode 1 will be OFF when no LINK is present. The LED_LINK pin in Mode 2 will be ON to indicate Link is good and BLINK to indicate activity is present on either transmit or receive activity. The LED_SPEED pin in DP83848K indicates 10 or 100 Mb/s data rate of the port. The standard CMOS driver goes high when operating in 100Mb/s operation. The functionality of this LED is independent of the mode selected. Since these LED pins are also used as strap options, the polarity of the LED is dependent on whether the pin is pulled up or down. 2.4.1 LED Since the Auto-Negotiation strap options share the LED output pins, the external components required for strapping and LED usage must be considered in order to avoid contention. Specifically, when the LED output is used to drive the LED directly, the active state of the output driver is dependent on the logic level sampled by the AN input upon powerup/reset. For example, if the AN input is resistively pulled low then the corresponding output will be configured as an active high driver. Conversely, if the AN input is resistively pulled high, then the corresponding output will be configured as an active low driver. Refer to Figure 3 for an example of AN connection to external components. In this example, the AN strapping results in Auto-Negotiation with 10BASE-T Half-Duplex , 100BASE-TX, Half-Duplex advertised. The adaptive nature of the LED output helps to simplify potential implementation issues of this dual purpose pin. www.national.com VCC 275Ω 1 LED_LINK AN0 = 0 LED_CFG [0] (bit 5) or (pin33) 2.2kΩ Mode LED_LINK LED_SPEED The DP83848K supports configurable Light Emitting Diode (LED) pins for configuring the link and speed. The PHY Control Register (PHYCR) for the LED can also be selected through address 19h, bit [5]. AN1 = 1 DP83848K 2.4 LED INTERFACE 18 The DP83848K supports both half and full duplex operation at both 10 Mb/s and 100 Mb/s speeds. Half-duplex relies on the CSMA/CD protocol to handle collisions and network access. In Half-Duplex mode, CRS responds to both transmit and receive activity in order to maintain compliance with the IEEE 802.3 specification. Since the DP83848K is designed to support simultaneous transmit and receive activity, it is capable of supporting fullduplex switched applications with a throughput of up to 200 Mb/s per port when operating in 100BASE-TX mode. Because the CSMA/CD protocol does not apply to fullduplex operation, the DP83848K disables its own internal collision sensing and reporting functions and modifies the behavior of Carrier Sense (CRS) such that it indicates only receive activity. This allows a full-duplex capable MAC to operate properly. All modes of operation (100BASE-TX and 10BASE-T) can run either half-duplex or full-duplex. Additionally, other than CRS and Collision reporting, all remaining MII signaling remains the same regardless of the selected duplex mode. It is important to understand that while Auto-Negotiation with the use of Fast Link Pulse code words can interpret and configure to full-duplex operation, parallel detection can not recognize the difference between full and halfduplex from a fixed 10 Mb/s or 100 Mb/s link partner over twisted pair. As specified in the 802.3u specification, if a far-end link partner is configured to a forced full duplex 100BASE-TX ability, the parallel detection state machine in the partner would be unable to detect the full duplex capability of the far-end link partner. This link segment would negotiate to a half duplex 100BASE-TX configuration (same scenario for 10 Mb/s). through bit 14 (Loopback) of the Basic Mode Control Register (BMCR). Writing 1 to this bit enables MII transmit data to be routed to the MII receive outputs. Loopback status may be checked in bit 3 of the PHY Status Register (PHYSTS). While in Loopback mode the data will not be transmitted onto the media. To ensure that the desired operating mode is maintained, Auto-Negotiation should be disabled before selecting the Loopback mode. 2.7 BIST The DP83848K incorporates an internal Built-in Self Test (BIST) circuit to accommodate in-circuit testing or diagnostics. The BIST circuit can be utilized to test the integrity of the transmit and receive data paths. BIST testing can be performed with the part in the internal loopback mode or externally looped back using a loopback cable fixture. The BIST is implemented with independent transmit and receive paths, with the transmit block generating a continuous stream of a pseudo random sequence. The user can select a 9 bit or 15 bit pseudo random sequence from the PSR_15 bit in the PHY Control Register (PHYCR). The received data is compared to the generated pseudo-random data by the BIST Linear Feedback Shift Register (LFSR) to determine the BIST pass/fail status. The pass/fail status of the BIST is stored in the BIST status bit in the PHYCR register. The status bit defaults to 0 (BIST fail) and will transition on a successful comparison. If an error (mis-compare) occurs, the status bit is latched and is cleared upon a subsequent write to the Start/Stop bit. For transmit VOD testing, the Packet BIST Continuous Mode can be used to allow continuous data transmission, setting BIST_CONT_MODE, bit 5, of CDCTRL1 (0x1Bh). The number of BIST errors can be monitored through the BIST Error Count in the CDCTRL1 (0x1Bh), bits [15:8]. 2.6 INTERNAL LOOPBACK The DP83848K includes a Loopback Test mode for facilitating system diagnostics. The Loopback mode is selected 19 www.national.com DP83848K 2.5 HALF DUPLEX VS. FULL DUPLEX DP83848K 3.0 Functional Description active simultaneously. Collisions are reported by the COL signal on the MII. The DP83848K supports two modes of operation using the MII interface pins. The options are defined in the following sections and include: If the DP83848K is transmitting in 10 Mb/s mode when a collision is detected, the collision is not reported until seven bits have been received while in the collision state. This prevents a collision being reported incorrectly due to noise on the network. The COL signal remains set for the duration of the collision. — MII Mode — RMII Mode The modes of operation can be selected by strap options or register control. For RMII mode, it is required to use the strap option, since it requires a 50 MHz clock instead of the normal 25 MHz. If a collision occurs during a receive operation, it is immediately reported by the COL signal. When heartbeat is enabled (only applicable to 10 Mb/s operation), approximately 1µs after the transmission of each packet, a Signal Quality Error (SQE) signal of approximately 10 bit times is generated (internally) to indicate successful transmission. SQE is reported as a pulse on the COL signal of the MII. In the each of these modes, the IEEE 802.3 serial management interface is operational for device configuration and status. The serial management interface of the MII allows for the configuration and control of multiple PHY devices, gathering of status, error information, and the determination of the type and capabilities of the attached PHY(s). 3.1.3 Carrier Sense Carrier Sense (CRS) is asserted due to receive activity, once valid data is detected via the squelch function during 10 Mb/s operation. During 100 Mb/s operation CRS is asserted when a valid link (SD) and two non-contiguous zeros are detected on the line. 3.1 MII INTERFACE The DP83848K incorporates the Media Independent Interface (MII) as specified in Clause 22 of the IEEE 802.3u standard. This interface may be used to connect PHY devices to a MAC in 10/100 Mb/s systems. This section describes the nibble wide MII data interface. For 10 or 100 Mb/s Half Duplex operation, CRS is asserted during either packet transmission or reception. The nibble wide MII data interface consists of a receive bus and a transmit bus each with control signals to facilitate data transfer between the PHY and the upper layer (MAC). For 10 or 100 Mb/s Full Duplex operation, CRS is asserted only due to receive activity. 3.1.1 Nibble-wide MII Data Interface 3.2 Reduced MII Interface Clause 22 of the IEEE 802.3u specification defines the Media Independent Interface. This interface includes a dedicated receive bus and a dedicated transmit bus. These two data buses, along with various control and status signals, allow for the simultaneous exchange of data between the DP83848K and the upper layer agent (MAC). The DP83848T incorporates the Reduced Media Independent Interface (RMII) as specified in the RMII specification (rev1.2) from the RMII Consortium. This interface may be used to connect PHY devices to a MAC in 10/100 Mb/s systems using a reduced number of pins. In this mode, data is transferred 2-bits at a time using the 50 MHz RMII_REF clock for both transmit and receive. The following pins are used in RMII mode: CRS is deasserted following an end of packet. The receive interface consists of a nibble wide data bus RXD[3:0], a receive error signal RX_ER, a receive data valid flag RX_DV, and a receive clock RX_CLK for synchronous transfer of the data. The receive clock operates at either 2.5 MHz to support 10 Mb/s operation modes or at 25 MHz to support 100 Mb/s operational modes. — TX_EN — TXD[1:0] — RX_ER (optional for Mac) — CRS_DV The transmit interface consists of a nibble wide data bus TXD[3:0], a transmit enable control signal TX_EN, and a transmit clock TX_CLK which runs at either 2.5 MHz or 25 MHz. — RXD[1:0] — X1 (RMII Reference clock is 50 MHz) In addition, the RMII mode supplies an RX_DV signal which allows for a simpler method of recovering receive data without having to separate RX_DV from the CRS_DV indication. This is especially useful for systems which do not require CRS, such as systems that only support fullduplex operation. This signal is also useful for diagnostic testing where it may be desirable to loop Receive RMII data directly to the transmitter. Additionally, the MII includes the carrier sense signal CRS, as well as a collision detect signal COL. The CRS signal asserts to indicate the reception of data from the network or as a function of transmit data in Half Duplex mode. The COL signal asserts as an indication of a collision which can occur during half-duplex operation when both a transmit and receive operation occur simultaneously. Since the reference clock operates at 10 times the data rate for 10 Mb/s operation, transmit data is sampled every 10 clocks. Likewise, receive data will be generated every 10th clock so that an attached device can sample the data every 10 clocks. 3.1.2 Collision Detect For Half Duplex, a 10BASE-T or 100BASE-TX collision is detected when the receive and transmit channels are www.national.com 20 The elasticity buffer will force Frame Check Sequence errors for packets which overrun or underrun the FIFO. To tolerate potential frequency differences between the 50 Underrun and Overrun conditions can be reported in the MHz reference clock and the recovered receive clock, the RMII and Bypass Register (RBR). The following table indireceive RMII function includes a programmable elasticity cates how to program the elasticity buffer fifo (in 4-bit increbuffer. The elasticity buffer is programmable to minimize ments) based on expected max packet size and clock propagation delay based on expected packet size and accuracy. It assumes both clocks (RMII Reference clock clock accuracy. This allows for supporting a range of and far-end Transmitter clock) have the same accuracy. packet sizes including jumbo frames. Table 4. Supported packet sizes at +/-50ppm +/-100ppm for each clock Start Threshold RBR[1:0] Latency Tolerance Recommended Packet Size at +/- 50ppm Recommended Packet Size at +/- 100ppm 1 (4-bits) 2 bits 2400 bytes 1200 bytes 2 (8-bits) 6 bits 7200 bytes 3600 bytes 3 (12-bits) 10 bits 12000 bytes 6000 bytes 0 (16-bits) 14 bits 16800 bytes 8400 bytes 3.3 802.3U MII SERIAL MANAGEMENT INTERFACE should be used to re-sync the device if an invalid start, opcode, or turnaround bit is detected. The DP83848K waits until it has received this preamble sequence before responding to any other transaction. Once the DP83848K serial management port has been ini3.3.1 Serial Management Register Access tialized no further preamble sequencing is required until The serial management MII specification defines a set of after a power-on/reset, invalid Start, invalid Opcode, or thirty-two 16-bit status and control registers that are acces- invalid turnaround bit has occurred. sible through the management interface pins MDC and MDIO. The DP83848K implements all the required MII reg- The Start code is indicated by a <01> pattern. This assures the MDIO line transitions from the default idle line state. isters as well as several optional registers. These registers are fully described in Section 7.0. A description of the serial Turnaround is defined as an idle bit time inserted between the Register Address field and the Data field. To avoid conmanagement access protocol follows. tention during a read transaction, no device shall actively drive the MDIO signal during the first bit of Turnaround. The addressed DP83848K drives the MDIO with a zero for 3.3.2 Serial Management Access Protocol the second bit of turnaround and follows this with the The serial control interface consists of two pins, Manage- required data. Figure 4 shows the timing relationship ment Data Clock (MDC) and Management Data Input/Out- between MDC and the MDIO as driven/received by the Staput (MDIO). MDC has a maximum clock rate of 25 MHz tion (STA) and the DP83848K (PHY) for a typical register and no minimum rate. The MDIO line is bi-directional and read access. may be shared by up to 32 devices. The MDIO frame for- For write transactions, the station management entity mat is shown below in Table 5.. writes data to the addressed DP83848K thus eliminating The MDIO pin requires a pull-up resistor (1.5 kΩ) which, during IDLE and turnaround, will pull MDIO high. In order to initialize the MDIO interface, the station management entity sends a sequence of 32 contiguous logic ones on MDIO to provide the DP83848K with a sequence that can be used to establish synchronization. This preamble may be generated either by driving MDIO high for 32 consecutive MDC clock cycles, or by simply allowing the MDIO pull-up resistor to pull the MDIO pin high during which time 32 MDC clock cycles are provided. In addition, 32 MDC clock cycles the requirement for MDIO Turnaround. The Turnaround time is filled by the management entity by inserting <10>. Figure 5 shows the timing relationship for a typical MII register write access. Table 5. Typical MDIO Frame Format MII Management Serial Protocol <idle><start><op code><device addr><reg addr><turnaround><data><idle> Read Operation <idle><01><10><AAAAA><RRRRR><Z0><xxxx xxxx xxxx xxxx><idle> Write Operation <idle><01><01><AAAAA><RRRRR><10><xxxx xxxx xxxx xxxx><idle> 21 www.national.com DP83848K RMII mode requires a 50 MHz oscillator be connected to the device X1 pin. A 50 MHz crystal is not supported. DP83848K MDC MDIO Z Z (STA) Z MDIO Z (PHY) Z 0 1 1 0 0 1 1 0 0 0 0 0 0 0 Idle Start Opcode (Read) PHY Address (PHYAD = 0Ch) Register Address (00h = BMCR) Z 0 0 0 1 1 0 0 0 1 0 0 0 0 0 0 0 0 TA Register Data Z Idle Figure 4. Typical MDC/MDIO Read Operation MDC MDIO Z Z (STA) Z Idle 0 1 0 1 0 1 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Start Opcode (Write) PHY Address (PHYAD = 0Ch) Register Address (00h = BMCR) TA Figure 5. Typical MDC/MDIO Write Operation 3.3.3 Serial Management Preamble Suppression The DP83848K supports a Preamble Suppression mode as indicated by a one in bit 6 of the Basic Mode Status Register (BMSR, address 01h.) If the station management entity (i.e. MAC or other management controller) determines that all PHYs in the system support Preamble Suppression by returning a one in this bit, then the station management entity need not generate preamble for each management transaction. The DP83848K requires a single initialization sequence of 32 bits of preamble following hardware/software reset. This requirement is generally met by the mandatory pullup resistor on MDIO in conjunction with a continuous MDC, or the management access made to determine whether Preamble Suppression is supported. While the DP83848K requires an initial preamble sequence of 32 bits for management initialization, it does not require a full 32-bit sequence between each subsequent transaction. A minimum of one idle bit between management transactions is required as specified in the IEEE 802.3u specification. www.national.com 22 Register Data Z Idle The block diagram in Figure 6. provides an overview of each functional block within the 100BASE-TX transmit secThis section describes the operations within each trans- tion. ceiver module, 100BASE-TX and 10BASE-T. Each operation consists of several functional blocks and described in The Transmitter section consists of the following functional blocks: the following: — 100BASE-TX Transmitter — 100BASE-TX Receiver — 10BASE-T Transceiver Module 4.1 100BASE-TX TRANSMITTER The 100BASE-TX transmitter consists of several functional blocks which convert synchronous 4-bit nibble data, as provided by the MII, to a scrambled MLT-3 125 Mb/s serial data stream. Because the 100BASE-TX TP-PMD is integrated, the differential output pins, PMD Output Pair, can be directly routed to the magnetics. — Code-group Encoder and Injection block — Scrambler block (bypass option) — NRZ to NRZI encoder block — Binary to MLT-3 converter / Common Driver The bypass option for the functional blocks within the 100BASE-TX transmitter provides flexibility for applications where data conversion is not always required. The DP83848K implements the 100BASE-TX transmit state machine diagram as specified in the IEEE 802.3u Standard, Clause 24. TX_CLK TXD[3:0] / TX_EN DIVIDE BY 5 4B5B CODE-GROUP ENCODER & INJECTOR 5B PARALLEL TO SERIAL 125MHZ CLOCK SCRAMBLER MUX BP_SCR 100BASE-TX LOOPBACK MLT[1:0] NRZ TO NRZI ENCODER BINARY TO MLT-3 / COMMON DRIVER PMD OUTPUT PAIR Figure 6. 100BASE-TX Transmit Block Diagram 23 www.national.com DP83848K 4.0 Architecture DP83848K Table 6. 4B5B Code-Group Encoding/Decoding DATA CODES 0 11110 0000 1 01001 0001 2 10100 0010 3 10101 0011 4 01010 0100 5 01011 0101 6 01110 0110 7 01111 0111 8 10010 1000 9 10011 1001 A 10110 1010 B 10111 1011 C 11010 1100 D 11011 1101 E 11100 1110 F 11101 1111 00100 HALT code-group - Error code IDLE AND CONTROL CODES H I 11111 Inter-Packet IDLE - 0000 (Note 1) J 11000 First Start of Packet - 0101 (Note 1) K 10001 Second Start of Packet - 0101 (Note 1) T 01101 First End of Packet - 0000 (Note 1) R 00111 Second End of Packet - 0000 (Note 1) INVALID CODES V 00000 V 00001 V 00010 V 00011 V 00101 V 00110 V 01000 V 01100 Note: Control code-groups I, J, K, T and R in data fields will be mapped as invalid codes, together with RX_ER asserted. www.national.com 24 The code-group encoder converts 4-bit (4B) nibble data generated by the MAC into 5-bit (5B) code-groups for transmission. This conversion is required to allow control data to be combined with packet data code-groups. Refer to Table 6. for 4B to 5B code-group mapping details. The code-group encoder substitutes the first 8-bits of the MAC preamble with a J/K code-group pair (11000 10001) upon transmission. The code-group encoder continues to replace subsequent 4B preamble and data nibbles with corresponding 5B code-groups. At the end of the transmit packet, upon the deassertion of Transmit Enable signal from the MAC, the code-group encoder injects the T/R code-group pair (01101 00111) indicating the end of the frame. transmit transformer primary winding, resulting in a MLT-3 signal. The 100BASE-TX MLT-3 signal sourced by the PMD Output Pair common driver is slew rate controlled. This should be considered when selecting AC coupling magnetics to ensure TP-PMD Standard compliant transition times (3 ns < Tr < 5 ns). The 100BASE-TX transmit TP-PMD function within the DP83848K is capable of sourcing only MLT-3 encoded data. Binary output from the PMD Output Pair is not possible in 100 Mb/s mode. 4.2 100BASE-TX RECEIVER After the T/R code-group pair, the code-group encoder continuously injects IDLEs into the transmit data stream until the next transmit packet is detected (reassertion of Transmit Enable). The 100BASE-TX receiver consists of several functional blocks which convert the scrambled MLT-3 125 Mb/s serial data stream to synchronous 4-bit nibble data that is provided to the MII. Because the 100BASE-TX TP-PMD is integrated, the differential input pins, RD±, can be directly routed from the AC coupling magnetics. 4.1.2 Scrambler See Figure 7 for a block diagram of the 100BASE-TX receive function. This provides an overview of each functional block within the 100BASE-TX receive section. The scrambler is required to control the radiated emissions at the media connector and on the twisted pair cable (for 100BASE-TX applications). By scrambling the data, the total energy launched onto the cable is randomly distributed over a wide frequency range. Without the scrambler, energy levels at the PMD and on the cable could peak beyond FCC limitations at frequencies related to repeating 5B sequences (i.e., continuous transmission of IDLEs). The Receive section consists of the following functional blocks: — — — — The scrambler is configured as a closed loop linear feed— back shift register (LFSR) with an 11-bit polynomial. The output of the closed loop LFSR is X-ORd with the serial — NRZ data from the code-group encoder. The result is a — scrambled data stream with sufficient randomization to — decrease radiated emissions at certain frequencies by as much as 20 dB. The DP83848K uses the PHY_ID (pins — — PHYAD [4:0]) to set a unique seed value. — Analog Front End Digital Signal Processor Signal Detect MLT-3 to Binary Decoder NRZI to NRZ Decoder Serial to Parallel Descrambler Code Group Alignment 4B/5B Decoder Link Integrity Monitor Bad SSD Detection 4.1.3 NRZ to NRZI Encoder After the transmit data stream has been serialized and scrambled, the data must be NRZI encoded in order to comply with the TP-PMD standard for 100BASE-TX transmission over Category-5 Unshielded twisted pair cable. 4.2.1 Analog Front End In addition to the Digital Equalization and Gain Control, the DP83848K includes Analog Equalization and Gain Control in the Analog Front End. The Analog Equalization reduces the amount of Digital Equalization required in the DSP. 4.1.4 Binary to MLT-3 Convertor The Binary to MLT-3 conversion is accomplished by converting the serial binary data stream output from the NRZI encoder into two binary data streams with alternately phased logic one events. These two binary streams are then fed to the twisted pair output driver which converts the voltage to current and alternately drives either side of the 4.2.2 Digital Signal Processor The Digital Signal Processor includes Adaptive Equalization with Gain Control and Base Line Wander Compensation. 25 www.national.com DP83848K 4.1.1 Code-group Encoding and Injection DP83848K RX_DV/CRS RX_CLK RXD[3:0] / RX_ER 4B/5B DECODER SERIAL TO PARALLEL CODE GROUP ALIGNMENT LINK INTEGRITY MONITOR RX_DATA VALID SSD DETECT DESCRAMBLER NRZI TO NRZ DECODER MLT-3 TO BINARY DECODER SIGNAL DETECT DIGITAL SIGNAL PROCESSOR ANALOG FRONT END RD +/− Figure 7. 100BASE-TX Receive Block Diagram www.national.com 26 When transmitting data at high speeds over copper twisted pair cable, frequency dependent attenuation becomes a concern. In high-speed twisted pair signalling, the frequency content of the transmitted signal can vary greatly during normal operation based primarily on the randomness of the scrambled data stream. This variation in signal attenuation caused by frequency variations must be compensated to ensure the integrity of the transmission. In order to ensure quality transmission when employing MLT-3 encoding, the compensation must be able to adapt to various cable lengths and cable types depending on the installed environment. The selection of long cable lengths for a given implementation, requires significant compensation which will over-compensate for shorter, less attenuating lengths. Conversely, the selection of short or intermediate cable lengths requiring less compensation will cause serious under-compensation for longer length cables. The compensation or equalization must be adap- tive to ensure proper conditioning of the received signal independent of the cable length. The DP83848K utilizes an extremely robust equalization scheme referred as ‘Digital Adaptive Equalization.’ The Digital Equalizer removes ISI (inter symbol interference) from the receive data stream by continuously adapting to provide a filter with the inverse frequency response of the channel. Equalization is combined with an adaptive gain control stage. This enables the receive 'eye pattern' to be opened sufficiently to allow very reliable data recovery. The curves given in Figure 8 illustrate attenuation at certain frequencies for given cable lengths. This is derived from the worst case frequency vs. attenuation figures as specified in the EIA/TIA Bulletin TSB-36. These curves indicate the significant variations in signal attenuation that must be compensated for by the receive adaptive equalization circuit. Figure 8. EIA/TIA Attenuation vs. Frequency for 0, 50, 100, 130 & 150 meters of CAT 5 cable 27 www.national.com DP83848K 4.2.2.1 Digital Adaptive Equalization and Gain Control DP83848K 4.2.2.2 Base Line Wander Compensation Figure 9. 100BASE-TX BLW Event The DP83848K is completely ANSI TP-PMD compliant and includes Base Line Wander (BLW) compensation. The BLW compensation block can successfully recover the TP-PMD defined “killer” pattern. 4.2.4 MLT-3 to NRZI Decoder The DP83848K decodes the MLT-3 information from the Digital Adaptive Equalizer block to binary NRZI data. BLW can generally be defined as the change in the average DC content, relatively short period over time, of an AC coupled digital transmission over a given transmission medium. (i.e., copper wire). 4.2.5 NRZI to NRZ In a typical application, the NRZI to NRZ decoder is required in order to present NRZ formatted data to the descrambler. BLW results from the interaction between the low frequency components of a transmitted bit stream and the frequency response of the AC coupling component(s) within the transmission system. If the low frequency content of the digital bit stream goes below the low frequency pole of the AC coupling transformers then the droop characteristics of the transformers will dominate resulting in potentially serious BLW. 4.2.6 Serial to Parallel The 100BASE-TX receiver includes a Serial to Parallel converter which supplies 5-bit wide data symbols to the PCS Rx state machine. The digital oscilloscope plot provided in Figure 9 illustrates the severity of the BLW event that can theoretically be generated during 100BASE-TX packet transmission. This event consists of approximately 800 mV of DC offset for a period of 120 µs. Left uncompensated, events such as this can cause packet loss. 4.2.3 Signal Detect The signal detect function of the DP83848K is incorporated to meet the specifications mandated by the ANSI FDDI TP-PMD Standard as well as the IEEE 802.3 100BASE-TX Standard for both voltage thresholds and timing parameters. Note that the reception of normal 10BASE-T link pulses and fast link pulses per IEEE 802.3u Auto-Negotiation by the 100BASE-TX receiver do not cause the DP83848K to assert signal detect. www.national.com 28 4.2.10 100BASE-TX Link Integrity Monitor A serial descrambler is used to de-scramble the received NRZ data. The descrambler has to generate an identical data scrambling sequence (N) in order to recover the original unscrambled data (UD) from the scrambled data (SD) as represented in the equations: The 100 Base TX Link monitor ensures that a valid and stable link is established before enabling both the Transmit and Receive PCS layer. SD = ( UD ⊕ N ) UD = ( SD ⊕ N ) Synchronization of the descrambler to the original scrambling sequence (N) is achieved based on the knowledge that the incoming scrambled data stream consists of scrambled IDLE data. After the descrambler has recognized 12 consecutive IDLE code-groups, where an unscrambled IDLE code-group in 5B NRZ is equal to five consecutive ones (11111), it will synchronize to the receive data stream and generate unscrambled data in the form of unaligned 5B code-groups. In order to maintain synchronization, the descrambler must continuously monitor the validity of the unscrambled data that it generates. To ensure this, a line state monitor and a hold timer are used to constantly monitor the synchronization status. Upon synchronization of the descrambler the hold timer starts a 722 µs countdown. Upon detection of sufficient IDLE code-groups (58 bit times) within the 722 µs period, the hold timer will reset and begin a new countdown. This monitoring operation will continue indefinitely given a properly operating network connection with good signal integrity. If the line state monitor does not recognize sufficient unscrambled IDLE code-groups within the 722 µs period, the entire descrambler will be forced out of the current state of synchronization and reset in order to reacquire synchronization. 4.2.8 Code-group Alignment Signal detect must be valid for 395us to allow the link monitor to enter the 'Link Up' state, and enable the transmit and receive functions. 4.2.11 Bad SSD Detection A Bad Start of Stream Delimiter (Bad SSD) is any transition from consecutive idle code-groups to non-idle code-groups which is not prefixed by the code-group pair /J/K. If this condition is detected, the DP83848K will assert RX_ER and present RXD[3:0] = 1110 to the MII for the cycles that correspond to received 5B code-groups until at least two IDLE code groups are detected. In addition, the False Carrier Sense Counter register (FCSCR) will be incremented by one. Once at least two IDLE code groups are detected, RX_ER and CRS become de-asserted. 4.3 10BASE-T TRANSCEIVER MODULE The 10BASE-T Transceiver Module is IEEE 802.3 compliant. It includes the receiver, transmitter, collision, heartbeat, loopback, jabber, and link integrity functions, as defined in the standard. An external filter is not required on the 10BASE-T interface since this is integrated inside the DP83848K. This section focuses on the general 10BASE-T system level operation. 4.3.1 Operational Modes The code-group alignment module operates on unaligned 5-bit data from the descrambler (or, if the descrambler is bypassed, directly from the NRZI/NRZ decoder) and converts it into 5B code-group data (5 bits). Code-group alignment occurs after the J/K code-group pair is detected. Once the J/K code-group pair (11000 10001) is detected, subsequent data is aligned on a fixed boundary. The DP83848K has two basic 10BASE-T operational modes: — Half Duplex mode — Full Duplex mode Half Duplex Mode 4.2.9 4B/5B Decoder The code-group decoder functions as a look up table that translates incoming 5B code-groups into 4B nibbles. The code-group decoder first detects the J/K code-group pair preceded by IDLE code-groups and replaces the J/K with MAC preamble. Specifically, the J/K 10-bit code-group pair is replaced by the nibble pair (0101 0101). All subsequent 5B code-groups are converted to the corresponding 4B nibbles for the duration of the entire packet. This conversion ceases upon the detection of the T/R code-group pair denoting the End of Stream Delimiter (ESD) or with the reception of a minimum of two IDLE code-groups. In Half Duplex mode the DP83848K functions as a standard IEEE 802.3 10BASE-T transceiver supporting the CSMA/CD protocol. Full Duplex Mode In Full Duplex mode the DP83848K is capable of simultaneously transmitting and receiving without asserting the collision signal. The DP83848K's 10 Mb/s ENDEC is designed to encode and decode simultaneously. 29 www.national.com DP83848K 4.2.7 Descrambler DP83848K 4.3.2 Smart Squelch within 150 ns. Finally the signal must again exceed the original squelch level within a 150 ns to ensure that the input waveform will not be rejected. This checking procedure results in the loss of typically three preamble bits at the beginning of each packet. The smart squelch is responsible for determining when valid data is present on the differential receive inputs. The DP83848K implements an intelligent receive squelch to ensure that impulse noise on the receive inputs will not be mistaken for a valid signal. Smart squelch operation is independent of the 10BASE-T operational mode. Only after all these conditions have been satisfied will a control signal be generated to indicate to the remainder of the circuitry that valid data is present. At this time, the smart squelch circuitry is reset. The squelch circuitry employs a combination of amplitude and timing measurements (as specified in the IEEE 802.3 10BSE-T standard) to determine the validity of data on the twisted pair inputs (refer to Figure 10). Valid data is considered to be present until the squelch level has not been generated for a time longer than 150 ns, indicating the End of Packet. Once good data has been detected, the squelch levels are reduced to minimize the effect of noise causing premature End of Packet detection. The signal at the start of a packet is checked by the smart squelch and any pulses not exceeding the squelch level (either positive or negative, depending upon polarity) will be rejected. Once this first squelch level is overcome correctly, the opposite squelch level must then be exceeded <150 ns >150 ns <150 ns VSQ+ VSQ+(reduced) VSQ-(reduced) VSQend of packet start of packet Figure 10. 10BASE-T Twisted Pair Smart Squelch Operation For 10 Mb/s Half Duplex operation, CRS is asserted during either packet transmission or reception. 4.3.3 Collision Detection and SQE For 10 Mb/s Full Duplex operation, CRS is asserted only during receive activity. When in Half Duplex, a 10BASE-T collision is detected when the receive and transmit channels are active simultaneously. Collisions are reported by the COL signal on the MII. Collisions are also reported when a jabber condition is detected. CRS is deasserted following an end of packet. 4.3.5 Normal Link Pulse Detection/Generation The link pulse generator produces pulses as defined in the IEEE 802.3 10BASE-T standard. Each link pulse is nominally 100 ns in duration and transmitted every 16 ms in the absence of transmit data. The COL signal remains set for the duration of the collision. If the PHY is receiving when a collision is detected it is reported immediately (through the COL pin). When heartbeat is enabled, approximately 1 µs after the transmission of each packet, a Signal Quality Error (SQE) signal of approximately 10-bit times is generated to indicate successful transmission. SQE is reported as a pulse on the COL signal of the MII. Link pulses are used to check the integrity of the connection with the remote end. If valid link pulses are not received, the link detector disables the 10BASE-T twisted pair transmitter, receiver and collision detection functions. When the link integrity function is disabled (FORCE_LINK_10 of the 10BTSCR register), a good link is forced and the 10BASE-T transceiver will operate regardless of the presence of link pulses. The SQE test is inhibited when the PHY is set in full duplex mode. SQE can also be inhibited by setting the HEARTBEAT_DIS bit in the 10BTSCR register. 4.3.4 Carrier Sense Carrier Sense (CRS) may be asserted due to receive activity once valid data is detected via the squelch function. www.national.com 30 4.3.8 Transmit and Receive Filtering The jabber function monitors the DP83848K's output and disables the transmitter if it attempts to transmit a packet of longer than legal size. A jabber timer monitors the transmitter and disables the transmission if the transmitter is active for approximately 85 ms. External 10BASE-T filters are not required when using the DP83848K, as the required signal conditioning is integrated into the device. Once disabled by the Jabber function, the transmitter stays disabled for the entire time that the ENDEC module's internal transmit enable is asserted. This signal has to be deasserted for approximately 500 ms (the “unjab” time) before the Jabber function re-enables the transmit outputs. The Jabber function is only relevant in 10BASE-T mode. Only isolation transformers and impedance matching resistors are required for the 10BASE-T transmit and receive interface. The internal transmit filtering ensures that all the harmonics in the transmit signal are attenuated by at least 30 dB. 4.3.9 Transmitter The encoder begins operation when the Transmit Enable input (TX_EN) goes high and converts NRZ data to pre4.3.7 Automatic Link Polarity Detection and Correction emphasized Manchester data for the transceiver. For the The DP83848K's 10BASE-T transceiver module incorpo- duration of TX_EN, the serialized Transmit Data (TXD) is rates an automatic link polarity detection circuit. When encoded for the transmit-driver pair (PMD Output Pair). three consecutive inverted link pulses are received, bad TXD must be valid on the rising edge of Transmit Clock (TX_CLK). Transmission ends when TX_EN deasserts. polarity is reported. The last transition is always positive; it occurs at the center A polarity reversal can be caused by a wiring error at either of the bit cell if the last bit is a one, or at the end of the bit end of the cable, usually at the Main Distribution Frame cell if the last bit is a zero. (MDF) or patch panel in the wiring closet. The bad polarity condition is latched in the 10BTSCR register. The DP83848K's 10BASE-T transceiver module cor- 4.3.10 Receiver rects for this error internally and will continue to decode received data correctly. This eliminates the need to correct The decoder detects the end of a frame when no additional mid-bit transitions are detected. Within one and a half bit the wiring error immediately. times after the last bit, carrier sense is de-asserted. Receive clock stays active for five more bit times after CRS goes low, to guarantee the receive timings of the controller. 31 www.national.com DP83848K 4.3.6 Jabber Function DP83848K 5.0 Design Guidelines 5.1 TPI NETWORK CIRCUIT Pulse H1102 Pulse H2019 Pulse J0011D21 Pulse J0011D21B Figure 11 shows the recommended circuit for a 10/100 Mb/s twisted pair interface. To the right is a partial list of recommended transformers. It is important that the user realize that variations with PCB and component characteristics requires that the application be tested to ensure that the circuit meets the requirements of the intended application. Vdd RDVdd COMMON MODE CHOKES MAY BE REQUIRED. 49.9Ω 0.1µF 1:1 49.9Ω RD+ RD- 0.1µF* RD+ TD- TD- TD+ 0.1µF* Vdd 49.9Ω 1:1 0.1µF RJ45 NOTE: CENTER TAP IS PULLED TO VDD 49.9Ω *PLACE CAPACITORS CLOSE TO THE TRANSFORMER CENTER TAPS TD+ All values are typical and are +/- 1% PLACE RESISTORS AND CAPACITORS CLOSE TO THE DEVICE. Figure 11. 10/100 Mb/s Twisted Pair Interface www.national.com T1 32 cal connection for a crystal resonator circuit. The load capacitor values will vary with the crystal vendors; check Typically, ESD precautions are predominantly in effect with the vendor for the recommended loads. when handling the devices or board before being installed in a system. In those cases, strict handling procedures The oscillator circuit is designed to drive a parallel resoneed be implemented during the manufacturing process to nance AT cut crystal with a minimum drive level of 100µW greatly reduce the occurrences of catastrophic ESD and a maximum of 500µW. If a crystal is specified for a events. After the system is assembled, internal compo- lower drive level, a current limiting resistor should be placed in series between X2 and the crystal. nents are less sensitive from ESD events. See Section 8.0 for ESD rating. As a starting point for evaluating an oscillator circuit, if the requirements for the crystal are not known, CL1 and CL2 should be set at 33 pF, and R1 should be set at 0Ω. 5.3 CLOCK IN (X1) RECOMMENDATIONS Specification for 25 MHz crystal are listed in Table 9.. The DP83848K supports an external CMOS level oscillator source or a crystal resonator device. Oscillator X2 X1 If an external clock source is used, X1 should be tied to the clock source and X2 should be left floating. The CMOS oscillator specifications for MII Mode are listed in Table 7.25 MHz Oscillator Specification. For RMII Mode, the CMOS oscillator specifications are listed in Table 8.50 MHz Oscillator Specification. For RMII mode, it is not recommended that the system clock out, Pin 21, be used as the reference clock to the MAC without first verifying the interface timing. See AN-1405 for more details. R1 CL1 CL2 Figure 12. Crystal Oscillator Circuit Crystal A 25 MHz, parallel, 20 pF load crystal resonator should be used if a crystal source is desired. Figure 12 shows a typiTable 7. 25 MHz Oscillator Specification Parameter Min Frequency Typ Max 25 Units Condition MHz +50 ppm Operational Temperature +50 ppm 1 year aging Rise / Fall Time 6 nsec 20% - 80% Jitter 8001 psec Short term Jitter 8001 psec Long term Frequency Tolerance Frequency Stability Symmetry 40% 60% Duty Cycle 1. This limit is provided as a guideline for component selection and not guaranteed by production testing. Refer to AN-1548, “PHYTER 100 Base-TX Reference Clock Jitter Tolerance,” for details on jitter performance. 33 www.national.com DP83848K 5.2 ESD PROTECTION DP83848K Table 8. 50 MHz Oscillator Specification Parameter Min Frequency Typ Max 25 Units Condition MHz +50 ppm Operational Temperature +50 ppm 1 year aging Rise / Fall Time 6 nsec 20% - 80% Jitter 8001 psec Short term Jitter 8001 psec Long term Frequency Tolerance Frequency Stability Symmetry 40% 60% Duty Cycle 1. This limit is provided as a guideline for component selection and not guaranteed by production testing. Refer to AN-1548, “PHYTER 100 Base-TX Reference Clock Jitter Tolerance,” for details on jitter performance. Table 9. 25 MHz Crystal Specification Parameter Min Frequency Typ Max 25 Units MHz Frequency +50 ppm Operational Temperature +50 ppm 1 year aging 40 pF Tolerance Frequency Stability Load Capacitance www.national.com Condition 25 34 5.6 ENERGY DETECT MODE To ensure correct operation for the DP83848K, parallel caps with values of 10 µF (Tantalum) and 0.1 µF should be placed close to pin 19 (PFBOUT) of the device. When Energy Detect is enabled and there is no activity on the cable, the DP83848K will remain in a low power mode while monitoring the transmission line. Activity on the line will cause the DP83848K to go through a normal power up sequence. Regardless of cable activity, the DP83848K will occasionally wake up the transmitter to put ED pulses on the line, but will otherwise draw as little power as possible. Energy detect functionality is controlled via register Energy Detect Control (EDCR), address 0x1Dh. Pin 16 (PFBIN1) and pin 30 (PFBIN2) must be connected to pin 19 (PFBOUT), each pin requires a small capacitor (0.1 µF). See Figure 13 below for proper connections. Pin 19 (PFBOUT) 10 µF + 0.1µF 6.0 Reset Operation Pin 16 (PFBIN1) 0.1 µF - The DP83848K includes an internal power-on reset (POR) function and does not need to be explicitly reset for normal operation after power up. If required during normal operation, the device can be reset by a hardware or software reset. Pin 30 (PFBIN2) 0.1 µF 6.1 HARDWARE RESET A hardware reset is accomplished by applying a low pulse (TTL level), with a duration of at least 1 µs, to the RESET_N. This will reset the device such that all registers will be reinitialized to default values and the hardware configuration values will be re-latched into the device (similar to the power-up/reset operation). Figure 13. Power Feedback Connection 5.5 POWER DOWN The device can be put in a Power Down mode by setting bit 11 (Power Down) in the Basic Mode Control Register, BMCR (0x00h). 6.2 SOFTWARE RESET A software reset is accomplished by setting the reset bit (bit 15) of the Basic Mode Control Register (BMCR). The period from the point in time when the reset bit is set to the point in time when software reset has concluded is approximately 1 µs. The software reset will reset the device such that all registers will be reset to default values and the hardware config- 35 www.national.com DP83848K 5.4 POWER FEEDBACK CIRCUIT DP83848K 7.0 Register Block Table 10. Register Map Offset Hex Decimal Access Tag Description 00h 0 RW BMCR Basic Mode Control Register 01h 1 RO BMSR Basic Mode Status Register 02h 2 RO PHYIDR1 PHY Identifier Register #1 03h 3 RO PHYIDR2 PHY Identifier Register #2 04h 4 RW ANAR Auto-Negotiation Advertisement Register 05h 5 RW ANLPAR Auto-Negotiation Link Partner Ability Register (Base Page) 05h 5 RW ANLPARNP Auto-Negotiation Link Partner Ability Register (Next Page) 06h 6 RW ANER Auto-Negotiation Expansion Register 07h 7 RW ANNPTR Auto-Negotiation Next Page TX 08h-Fh 8-15 RW RESERVED RESERVED 10h 16 RO PHYSTS PHY Status Register 11h 17 RW RESERVED RESERVED 12h 18 RO RESERVED RESERVED 13h 19 RW RESERVED RESERVED 14h 20 RW FCSCR False Carrier Sense Counter Register 15h 21 RW RECR Receive Error Counter Register 16h 22 RW PCSR PCS Sub-Layer Configuration and Status Register Extended Registers 17h 23 RW RBR RMII and Bypass Register 18h 24 RW LEDCR LED Direct Control Register 19h 25 RW PHYCR PHY Control Register 1Ah 26 RW 10BTSCR 10Base-T Status/Control Register 1Bh 27 RW CDCTRL1 CD Test Control Register and BIST Extensions Register 1Ch 28 RW RESERVED RESERVED 1Dh 29 RW EDCR Energy Detect Control Register 1Eh-1Fh 30-31 RW RESERVED RESERVED www.national.com 36 www.national.com 11h 12h 13h 14h 15h 16h RESERVED RESERVED RESERVED False Carrier Sense Counter Register Receive Error Counter Register PCS Sub-Layer Configuration and Status Register 06h Auto-Negotiation Expansion Register 10h 05h Auto-Negotiation Link Partner Ability Register Next Page PHY Status Register 05h Auto-Negotiation Link Partner Ability Register (Base Page) 08-0fh 04h Auto-Negotiation Advertisement Register RESERVED 03h PHY Identifier Register 2 07h 02h PHY Identifier Register 1 Auto-Negotiation Next Page TX Register 01h Basic Mode Status Register Addr 00h Register Name Basic Mode Control Register Tag Next Page Ind OUI LSB Reserved PCSR RECR FCSCR Reserved Reserved Reserved Reserved Reserved Reserved Reserved Reserved Reserved PHYSTS Reserved Reserved ANNPTR Next Page Ind Reserved ANNext LPARNP Page Ind ANER AutoNeg Enable 100Base 100Base 10BaseT -TX FDX -TX HDX FDX Speed Selection 10BaseT HDX Power Down Reserved Isolate Bit 9 Reserved Restart AutoNeg Bit 8 Reserved Duplex Mode Bit 7 Reserved Collision Test MF Preamble Suppress Reserved Bit 6 AutoNeg Complete Reserved Bit 5 Remote Fault Reserved Bit 4 AutoNeg Ability Reserved Bit 3 Link Status Reserved Bit 2 Jabber Detect Reserved Bit 1 Extended Capability Reserved Bit 0 Reserved Reserved Reserved Reserved Reserved Reserved MDI-X mode Reserved Reserved Reserved ACK ACK Reserved Reserved ACK2 Reserved ACK2 Reserved Reserved Reserved TOG_TX Reserved Toggle ASM_DI R ASM_DI R Reserved CODE Reserved Code PAUSE PAUSE Reserved Reserved Reserved Reserved Reserved Reserved Rx Err Latch Reserved Reserved Reserved Reserved Reserved Reserved Polarity Status Reserved Reserved Reserved Reserved Reserved Reserved False Carrier Sense TQ_EN Reserved Reserved Reserved Reserved Reserved Signal Detect EXTENDED REGISTERS Reserved Message Page Reserved Message Page Remote Fault Remote Fault OUI LSB OUI LSB OUI LSB OUI LSB OUI LSB Reserved Reserved Reserved Reserved Reserved Page Receive Reserved CODE Reserved Code TX_FD TX_FD VNDR_ MDL Reserved Reserved Reserved Remote Fault Reserved CODE Reserved Code 10_FD 10_FD VNDR_ MDL Reserved Reserved Reserved Jabber Detect Reserved CODE Reserved Code 10 10 VNDR_ MDL MDL_ REV MDL_ REV MDL_ REV MDL_ REV Reserved Reserved Reserved AutoNeg Complete Reserved CODE PDF Code Reserved Reserved Reserved Loopback Status Reserved CODE LP_NP_ ABLE Code Reserved Reserved Reserved Duplex Status Reserved CODE NP_ ABLE Code Reserved Reserved Reserved Speed Status Reserved CODE PAGE_ RX Code Reserved Reserved Reserved Link Status Reserved CODE LP_AN_ ABLE Code Protocol Protocol Protocol Protocol Protocol Selection Selection Selection Selection Selection Protocol Protocol Protocol Protocol Protocol Selection Selection Selection Selection Selection VNDR_ MDL RXERCNT Reserved RXERCNT FORCE_ 100_OK RXERCNT Reserved RXERCNT Reserved RXERCNT RXERCNT RXERCNT NRZI_ SCRAM_ DE BYPASS BYPASS SCRAM_ BYPASS RXERCNT FCSCNT FCSCNT FCSCNT FCSCNT FCSCNT FCSCNT FCSCNT FCSCNT Reserved Reserved Reserved Reserved Reserved CODE Reserved Code TX TX VNDR_ MDL SD_FOR SD_ DESC_T CE_PMA OPTION IME Reserved Reserved Reserved Reserved Reserved Descram Lock Reserved CODE Reserved Code T4 T4 VNDR_ MDL OUI MSB OUI MSB OUI MSB OUI MSB OUI MSB OUI MSB OUI MSB OUI MSB OUI MSB OUI MSB OUI MSB OUI MSB OUI MSB OUI MSB OUI MSB OUI MSB 100Base -T4 Loopback Bit 15 Bit 14 Bit 13 Bit 12 Bit 11 Bit 10 Reset ANLPAR Next Page Ind ANAR PHYIDR 2 PHYIDR 1 BMSR BMCR Table 11. Register Table DP83848K 37 www.national.com 38 18h 19h 1Ah 1Bh 1Ch 1Dh 1Eh-1Fh LED Direct Control Register PHY Control Register 10Base-T Status/Control Register CD Test Control and BIST Extensions Register RESERVED Energy Detect Control Register RESERVED Addr 17h Register Name RMII and Bypass Register Tag Reserved MDIX_E N Reserved Reserved Reserved Reserved Reserved Reserved Reserved Reserved FORCE_ PAUSE_ PAUSE_ MDIX RX TX Reserved Reserved PSR_15 Reserved Reserved Bit 9 Bit 8 Reserved Reserved Reserved EDCR Reserved Reserved ED_EN Reserved Reserved Reserved Reserved Reserved Reserved Reserved Reserved Reserved Reserved ED_AUT ED_AUT ED_MAN ED_BUR ED_PW O_UP O_DOW ST_DIS R_STAT N E Reserved Bit 7 Reserved Reserved Reserved Reserved Bit 6 Reserved Reserved FORC_ LINK_10 Reserved Reserved Reserved Bit 5 Bit 4 Reserved BIST_C ONT_M ODE Reserved LED_ CNFG[0] Bit 3 Bit 2 Bit 1 Bit 0 V1_0 Reserved CDPattE N_10 POLARITY PHY ADDR Reserved Reserved Reserved PHY ADDR Reserved _STS Reserved 10Meg_ Patt_Ga p Reserved PHY ADDR SPDLED _STS PHY ADDR Reserved PTR[0] Reserved CDPattSel Reserved CDPattSel HEART_ JABBER DIS _DIS PHY ADDR LNKLED PTR[1] RMII_RE RX_OVF RX_UNF RX_RD_ RX_RD_ DRV_SP DRV_LN DLED KLED ODE RMII_M Reserved Reserved Reserved Reserved Reserved Reserved Reserved Reserved Reserved Reserved ED_ERR ED_DAT ED_ERR ED_ERR ED_ERR ED_ERR ED_DAT ED_DAT ED_DAT ED_DAT _MET A_MET _COUNT _COUNT _COUNT _COUNT A_COUN A_COUN A_COUN A_COUN T T T T Reserved Reserved LP_DIS BIST_ BIST_ST BP_STR STATUS ART ETCH Reserved Reserved SQUELC SQUELC SQUELC LOOPBA H H H CK_10_ DIS BIST_fe Reserved Reserved Bit 15 Bit 14 Bit 13 Bit 12 Bit 11 Bit 10 Reserved CDCTRL BIST_ER BIST_ER BIST_ER BIST_ER BIST_ER BIST_ER BIST_ER BIST_ER 1 ROR_C ROR_C ROR_C ROR_C ROR_C ROR_C ROR_C ROR_C OUNT OUNT OUNT OUNT OUNT OUNT OUNT OUNT 10BT_S CR PHYCR LEDCR RBR Table 11. Register Table DP83848K DP83848K 7.1 REGISTER DEFINITION In the register definitions under the ‘Default’ heading, the following definitions hold true: — RW=Read Write access — — — — — — — — SC=Register sets on event occurrence and Self-Clears when event ends RW/SC =Read Write access/Self Clearing bit RO=Read Only access COR = Clear on Read RO/COR=Read Only, Clear on Read RO/P=Read Only, Permanently set to a default value LL=Latched Low and held until read, based upon the occurrence of the corresponding event LH=Latched High and held until read, based upon the occurrence of the corresponding event 39 www.national.com DP83848K 7.1.1 Basic Mode Control Register (BMCR) Table 12. Basic Mode Control Register (BMCR), address 0x00 Bit Bit Name Default 15 Reset 0, RW/SC Description Reset: 1 = Initiate software Reset / Reset in Process. 0 = Normal operation. This bit, which is self-clearing, returns a value of one until the reset process is complete. The configuration is re-strapped. 14 Loopback 0, RW Loopback: 1 = Loopback enabled. 0 = Normal operation. The loopback function enables MII transmit data to be routed to the MII receive data path. Setting this bit may cause the descrambler to lose synchronization and produce a 500 µs “dead time” before any valid data will appear at the MII receive outputs. 13 Speed Selection RW Speed Select: When auto-negotiation is disabled writing to this bit allows the port speed to be selected. 1 = 100 Mb/s. 0 = 10 Mb/s. 12 Auto-Negotiation Enable RW Auto-Negotiation Enable: Strap controls initial value at reset. 1 = Auto-Negotiation Enabled - bits 8 and 13 of this register are ignored when this bit is set. 0 = Auto-Negotiation Disabled - bits 8 and 13 determine the port speed and duplex mode. 11 Power Down 0, RW Power Down: 1 = Power down. 0 = Normal operation. Setting this bit powers down the PHY. Only the register block is enabled during a power down condition. 10 Isolate 0, RW Isolate: 1 = Isolates the Port from the MII with the exception of the serial management. 0 = Normal operation. 9 Restart AutoNegotiation 0, RW/SC Restart Auto-Negotiation: 1 = Restart Auto-Negotiation. Re-initiates the Auto-Negotiation process. If Auto-Negotiation is disabled (bit 12 = 0), this bit is ignored. This bit is self-clearing and will return a value of 1 until Auto-Negotiation is initiated, whereupon it will self-clear. Operation of the Auto-Negotiation process is not affected by the management entity clearing this bit. 0 = Normal operation. 8 Duplex Mode RW Duplex Mode: When auto-negotiation is disabled writing to this bit allows the port Duplex capability to be selected. 1 = Full Duplex operation. 0 = Half Duplex operation. www.national.com 40 DP83848K Table 12. Basic Mode Control Register (BMCR), address 0x00 (Continued) Bit Bit Name Default 7 Collision Test 0, RW Description Collision Test: 1 = Collision test enabled. 0 = Normal operation. When set, this bit will cause the COL signal to be asserted in response to the assertion of TX_EN within 512-bit times. The COL signal will be de-asserted within 4-bit times in response to the de-assertion of TX_EN. 6:0 RESERVED 0, RO RESERVED: Write ignored, read as 0. 41 www.national.com DP83848K 7.1.2 Basic Mode Status Register (BMSR) Table 13. Basic Mode Status Register (BMSR), address 0x01 Bit Bit Name Default 15 100BASE-T4 0, RO/P Description 100BASE-T4 Capable: 0 = Device not able to perform 100BASE-T4 mode. 14 100BASE-TX 1, RO/P Full Duplex 13 100BASE-TX 1 = Device able to perform 100BASE-TX in full duplex mode. 1, RO/P Half Duplex 12 10BASE-T 10BASE-T 100BASE-TX Half Duplex Capable: 1 = Device able to perform 100BASE-TX in half duplex mode. 1, RO/P Full Duplex 11 100BASE-TX Full Duplex Capable: 10BASE-T Full Duplex Capable: 1 = Device able to perform 10BASE-T in full duplex mode. 1, RO/P Half Duplex 10BASE-T Half Duplex Capable: 1 = Device able to perform 10BASE-T in half duplex mode. 10:7 RESERVED 0, RO RESERVED: Write as 0, read as 0. 6 MF Preamble 1, RO/P Preamble suppression Capable: Suppression 1 = Device able to perform management transaction with preamble suppressed, 32-bits of preamble needed only once after reset, invalid opcode or invalid turnaround. 0 = Normal management operation. 5 Auto-Negotiation Complete 0, RO Auto-Negotiation Complete: 1 = Auto-Negotiation process complete. 0 = Auto-Negotiation process not complete. 4 Remote Fault 0, RO/LH Remote Fault: 1 = Remote Fault condition detected (cleared on read or by reset). Fault criteria: Far End Fault Indication or notification from Link Partner of Remote Fault. 0 = No remote fault condition detected. 3 Auto-Negotiation Ability 1, RO/P Auto Negotiation Ability: 1 = Device is able to perform Auto-Negotiation. 0 = Device is not able to perform Auto-Negotiation. 2 Link Status 0, RO/LL Link Status: 1 = Valid link established (for either 10 or 100 Mb/s operation). 0 = Link not established. The criteria for link validity is implementation specific. The occurrence of a link failure condition will causes the Link Status bit to clear. Once cleared, this bit may only be set by establishing a good link condition and a read via the management interface. 1 Jabber Detect 0, RO/LH Jabber Detect: This bit only has meaning in 10 Mb/s mode. 1 = Jabber condition detected. 0 = No Jabber. This bit is implemented with a latching function, such that the occurrence of a jabber condition causes it to set until it is cleared by a read to this register by the management interface or by a reset. 0 Extended Capability 1, RO/P Extended Capability: 1 = Extended register capabilities. 0 = Basic register set capabilities only. www.national.com 42 7.1.3 PHY Identifier Register #1 (PHYIDR1) Table 14. PHY Identifier Register #1 (PHYIDR1), address 0x02 Bit Bit Name 15:0 OUI_MSB Default Description <0010 0000 0000 OUI Most Significant Bits: Bits 3 to 18 of the OUI (080017h) are 0000>, RO/P stored in bits 15 to 0 of this register. The most significant two bits of the OUI are ignored (the IEEE standard refers to these as bits 1 and 2). 7.1.4 PHY Identifier Register #2 (PHYIDR2) Table 15. PHY Identifier Register #2 (PHYIDR2), address 0x03 Bit Bit Name 15:10 OUI_LSB Default Description <0101 11>, RO/P OUI Least Significant Bits: Bits 19 to 24 of the OUI (080017h) are mapped from bits 15 to 10 of this register respectively. 9:4 VNDR_MDL <00 1001>, RO/P Vendor Model Number: The six bits of vendor model number are mapped from bits 9 to 4 (most significant bit to bit 9). 3:0 MDL_REV <0000>, RO/P Model Revision Number: Four bits of the vendor model revision number are mapped from bits 3 to 0 (most significant bit to bit 3). This field will be incremented for all major device changes. 7.1.5 Auto-Negotiation Advertisement Register (ANAR) This register contains the advertised abilities of this device as they will be transmitted to its link partner during Auto-Negotiation. Any writes to this register prior to completion of Auto-Negotiation (as indicated in the Basic Mode Status Register (address 0x01) Auto-Negotiation complete bit, BMSR[5] ) should be followed by a renegotiation. This will ensure that the new values are properly used in the Auto-Negotiation. Table 16. Negotiation Advertisement Register (ANAR), address 0x04 Bit Bit Name Default 15 NP 0, RW Description Next Page Indication: 0 = Next Page Transfer not desired. 1 = Next Page Transfer desired. 14 RESERVED 0, RO/P 13 RF 0, RW RESERVED by IEEE: Writes ignored, Read as 0. Remote Fault: 1 = Advertises that this device has detected a Remote Fault. 0 = No Remote Fault detected. 12 RESERVED 0, RW RESERVED for Future IEEE use: Write as 0, Read as 0 43 www.national.com DP83848K The PHY Identifier Registers #1 and #2 together form a unique identifier for the DP83848K. The Identifier consists of a concatenation of the Organizationally Unique Identifier (OUI), the vendor's model number and the model revision number. A PHY may return a value of zero in each of the 32 bits of the PHY Identifier if desired. The PHY Identifier is intended to support network management. National's IEEE assigned OUI is 080017h. DP83848K Table 16. Negotiation Advertisement Register (ANAR), address 0x04 (Continued) Bit Bit Name Default 11 ASM_DIR 0, RW Description Asymmetric PAUSE Support for Full Duplex Links: The ASM_DIR bit indicates that asymmetric PAUSE is supported. Encoding and resolution of PAUSE bits is defined in IEEE 802.3 Annex 28B, Tables 28B-2 and 28B-3, respectively. Pause resolution status is reported in PHYCR[13:12]. 1 = Advertise that the DTE (MAC) has implemented both the optional MAC control sublayer and the pause function as specified in clause 31 and annex 31B of 802.3u. 0= No MAC based full duplex flow control. 10 PAUSE 0, RW PAUSE Support for Full Duplex Links: The PAUSE bit indicates that the device is capable of providing the symmetric PAUSE functions as defined in Annex 31B. Encoding and resolution of PAUSE bits is defined in IEEE 802.3 Annex 28B, Tables 28B-2 and 28B-3, respectively. Pause resolution status is reported in PHYCR[13:12]. 1 = Advertise that the DTE (MAC) has implemented both the optional MAC control sublayer and the pause function as specified in clause 31 and annex 31B of 802.3u. 0= No MAC based full duplex flow control. 9 T4 0, RO/P 100BASE-T4 Support: 1= 100BASE-T4 is supported by the local device. 0 = 100BASE-T4 not supported. 8 TX_FD Strap, RW 100BASE-TX Full Duplex Support: 1 = 100BASE-TX Full Duplex is supported by the local device. 0 = 100BASE-TX Full Duplex not supported. 7 TX Strap, RW 100BASE-TX Support: 1 = 100BASE-TX is supported by the local device. 0 = 100BASE-TX not supported. 6 10_FD RW 10BASE-T Full Duplex Support: 1 = 10BASE-T Full Duplex is supported by the local device. 0 = 10BASE-T Full Duplex not supported. 5 10 RW 10BASE-T Support: 1 = 10BASE-T is supported by the local device. 0 = 10BASE-T not supported. 4:0 Selector <00001>, RW Protocol Selection Bits: These bits contain the binary encoded protocol selector supported by this port. <00001> indicates that this device supports IEEE 802.3u. www.national.com 44 This register contains the advertised abilities of the Link Partner as received during Auto-Negotiation. The content changes after the successful auto-negotiation if Next-pages are supported. Table 17. Auto-Negotiation Link Partner Ability Register (ANLPAR) (BASE Page), address 0x05 Bit Bit Name Default 15 NP 0, RO Description Next Page Indication: 0 = Link Partner does not desire Next Page Transfer. 1 = Link Partner desires Next Page Transfer. 14 ACK 0, RO Acknowledge: 1 = Link Partner acknowledges reception of the ability data word. 0 = Not acknowledged. The Auto-Negotiation state machine will automatically control the this bit based on the incoming FLP bursts. 13 RF 0, RO Remote Fault: 1 = Remote Fault indicated by Link Partner. 0 = No Remote Fault indicated by Link Partner. 12 RESERVED 0, RO RESERVED for Future IEEE use: Write as 0, read as 0. 11 ASM_DIR 0, RO ASYMMETRIC PAUSE: 1 = Asymmetric pause is supported by the Link Partner. 0 = Asymmetric pause is not supported by the Link Partner. 10 PAUSE 0, RO PAUSE: 1 = Pause function is supported by the Link Partner. 0 = Pause function is not supported by the Link Partner. 9 T4 0, RO 100BASE-T4 Support: 1 = 100BASE-T4 is supported by the Link Partner. 0 = 100BASE-T4 not supported by the Link Partner. 8 TX_FD 0, RO 100BASE-TX Full Duplex Support: 1 = 100BASE-TX Full Duplex is supported by the Link Partner. 0 = 100BASE-TX Full Duplex not supported by the Link Partner. 7 TX 0, RO 100BASE-TX Support: 1 = 100BASE-TX is supported by the Link Partner. 0 = 100BASE-TX not supported by the Link Partner. 6 10_FD 0, RO 10BASE-T Full Duplex Support: 1 = 10BASE-T Full Duplex is supported by the Link Partner. 0 = 10BASE-T Full Duplex not supported by the Link Partner. 5 10 0, RO 10BASE-T Support: 1 = 10BASE-T is supported by the Link Partner. 0 = 10BASE-T not supported by the Link Partner. 4:0 Selector <0 0000>, RO Protocol Selection Bits: Link Partner’s binary encoded protocol selector. 45 www.national.com DP83848K 7.1.6 Auto-Negotiation Link Partner Ability Register (ANLPAR) (BASE Page) DP83848K 7.1.7 Auto-Negotiation Link Partner Ability Register (ANLPAR) (Next Page) Table 18. Auto-Negotiation Link Partner Ability Register (ANLPAR) (Next Page), address 0x05 Bit Bit Name Default 15 NP 0, RO Description Next Page Indication: 1 = Link Partner desires Next Page Transfer. 0 = Link Partner does not desire Next Page Transfer. 14 ACK 0, RO Acknowledge: 1 = Link Partner acknowledges reception of the ability data word. 0 = Not acknowledged. The Auto-Negotiation state machine will automatically control the this bit based on the incoming FLP bursts. Software should not attempt to write to this bit. 13 MP 0, RO Message Page: 1 = Message Page. 0 = Unformatted Page. 12 ACK2 0, RO Acknowledge 2: 1 = Link Partner does have the ability to comply to next page message. 0 = Link Partner does not have the ability to comply to next page message. 11 Toggle 0, RO Toggle: 1 = Previous value of the transmitted Link Code word equalled 0. 0 = Previous value of the transmitted Link Code word equalled 1. 10:0 CODE <000 0000 0000>, Code: RO This field represents the code field of the next page transmission. If the MP bit is set (bit 13 of this register), then the code shall be interpreted as a “Message Page,” as defined in annex 28C of Clause 28. Otherwise, the code shall be interpreted as an “Unformatted Page,” and the interpretation is application specific. 7.1.8 Auto-Negotiate Expansion Register (ANER) This register contains additional Local Device and Link Partner status information. Table 19. Auto-Negotiate Expansion Register (ANER), address 0x06 Bit Bit Name Default Description 15:5 RESERVED 0, RO RESERVED: Writes ignored, Read as 0. 4 PDF 0, RO Parallel Detection Fault: 1 = A fault has been detected via the Parallel Detection function. 0 = A fault has not been detected. 3 LP_NP_ABLE 0, RO Link Partner Next Page Able: 1 = Link Partner does support Next Page. 0 = Link Partner does not support Next Page. 2 NP_ABLE 1, RO/P 1 PAGE_RX 0, RO/COR Next Page Able: 1 = Indicates local device is able to send additional “Next Pages”. Link Code Word Page Received: 1 = Link Code Word has been received, cleared on a read. 0 = Link Code Word has not been received. www.national.com 46 Bit Bit Name Default 0 LP_AN_ABLE 0, RO Description Link Partner Auto-Negotiation Able: 1 = indicates that the Link Partner supports Auto-Negotiation. 0 = indicates that the Link Partner does not support Auto-Negotiation. 7.1.9 Auto-Negotiation Next Page Transmit Register (ANNPTR) This register contains the next page information sent by this device to its Link Partner during Auto-Negotiation. Table 20. Auto-Negotiation Next Page Transmit Register (ANNPTR), address 0x07 Bit Bit Name Default 15 NP 0, RW Description Next Page Indication: 0 = No other Next Page Transfer desired. 1 = Another Next Page desired. 14 RESERVED 0, RO RESERVED: Writes ignored, read as 0. 13 MP 1, RW Message Page: 1 = Message Page. 0 = Unformatted Page. 12 ACK2 0, RW Acknowledge2: 1 = Will comply with message. 0 = Cannot comply with message. Acknowledge2 is used by the next page function to indicate that Local Device has the ability to comply with the message received. 11 TOG_TX 0, RO Toggle: 1 = Value of toggle bit in previously transmitted Link Code Word was 0. 0 = Value of toggle bit in previously transmitted Link Code Word was 1. Toggle is used by the Arbitration function within Auto-Negotiation to ensure synchronization with the Link Partner during Next Page exchange. This bit shall always take the opposite value of the Toggle bit in the previously exchanged Link Code Word. 10:0 CODE <000 0000 0001>, This field represents the code field of the next page transmission. RW If the MP bit is set (bit 13 of this register), then the code shall be interpreted as a "Message Page”, as defined in annex 28C of IEEE 802.3u. Otherwise, the code shall be interpreted as an "Unformatted Page”, and the interpretation is application specific. The default value of the CODE represents a Null Page as defined in Annex 28C of IEEE 802.3u. 47 www.national.com DP83848K Table 19. Auto-Negotiate Expansion Register (ANER), address 0x06 (Continued) DP83848K 7.2 EXTENDED REGISTERS 7.2.1 PHY Status Register (PHYSTS) This register provides a single location within the register set for quick access to commonly accessed information. Table 21. PHY Status Register (PHYSTS), address 0x10 Bit Bit Name Default Description 15 RESERVED 0, RO RESERVED: Write ignored, read as 0. 14 MDI-X mode 0, RO MDI-X mode as reported by the Auto-Negotiation logic: This bit will be affected by the settings of the MDIX_EN and FORCE_MDIX bits in the PHYCR register. When MDIX is enabled, but not forced, this bit will update dynamically as the Auto-MDIX algorithm swaps between MDI and MDI-X configurations. 1 = MDI pairs swapped (Receive on TPTD pair, Transmit on TPRD pair) 0 = MDI pairs normal (Receive on TRD pair, Transmit on TPTD pair) 13 Receive Error Latch 0, RO/LH Receive Error Latch: This bit will be cleared upon a read of the RECR register. 1 = Receive error event has occurred since last read of RXERCNT (address 0x15, Page 0). 0 = No receive error event has occurred. 12 Polarity Status 0, RO Polarity Status: This bit is a duplication of bit 4 in the 10BTSCR register. This bit will be cleared upon a read of the 10BTSCR register, but not upon a read of the PHYSTS register. 1 = Inverted Polarity detected. 0 = Correct Polarity detected. 11 False Carrier Sense Latch 0, RO/LH False Carrier Sense Latch: This bit will be cleared upon a read of the FCSR register. 1 = False Carrier event has occurred since last read of FCSCR (address 0x14). 0 = No False Carrier event has occurred. 10 Signal Detect 0, RO/LL 100Base-TX unconditional Signal Detect from PMD. 9 Descrambler Lock 0, RO/LL 100Base-TX Descrambler Lock from PMD. 8 Page Received 0, RO Link Code Word Page Received: This is a duplicate of the Page Received bit in the ANER register, but this bit will not be cleared upon a read of the PHYSTS register. 1 = A new Link Code Word Page has been received. Cleared on read of the ANER (address 0x06, bit 1). 0 = Link Code Word Page has not been received. 7 RESERVED 0, RO RESERVED: Writes ignored, read as 0. 6 Remote Fault 0, RO Remote Fault: 1 = Remote Fault condition detected (cleared on read of BMSR (address 01h) register or by reset). Fault criteria: notification from Link Partner of Remote Fault via Auto-Negotiation. 0 = No remote fault condition detected. 5 Jabber Detect 0, RO Jabber Detect: This bit only has meaning in 10 Mb/s mode This bit is a duplicate of the Jabber Detect bit in the BMSR register, except that it is not cleared upon a read of the PHYSTS register. 1 = Jabber condition detected. 0 = No Jabber. www.national.com 48 DP83848K Table 21. PHY Status Register (PHYSTS), address 0x10 (Continued) Bit Bit Name Default 4 Auto-Neg Complete 0, RO Description Auto-Negotiation Complete: 1 = Auto-Negotiation complete. 0 = Auto-Negotiation not complete. 3 Loopback Status 0, RO Loopback: 1 = Loopback enabled. 0 = Normal operation. 2 Duplex Status 0, RO Duplex: This bit indicates duplex status and is determined from Auto-Negotiation or Forced Modes. 1 = Full duplex mode. 0 = Half duplex mode. Note: This bit is only valid if Auto-Negotiation is enabled and complete and there is a valid link or if Auto-Negotiation is disabled and there is a valid link. 1 Speed Status 0, RO Speed10: This bit indicates the status of the speed and is determined from Auto-Negotiation or Forced Modes. 1 = 10 Mb/s mode. 0 = 100 Mb/s mode. Note: This bit is only valid if Auto-Negotiation is enabled and complete and there is a valid link or if Auto-Negotiation is disabled and there is a valid link. 0 Link Status 0, RO Link Status: This bit is a duplicate of the Link Status bit in the BMSR register, except that it will not be cleared upon a read of the PHYSTS register. 1 = Valid link established (for either 10 or 100 Mb/s operation) 0 = Link not established. 49 www.national.com DP83848K 7.2.2 False Carrier Sense Counter Register (FCSCR) This counter provides information required to implement the “False Carriers” attribute within the MAU managed object class of Clause 30 of the IEEE 802.3u specification. Table 22. False Carrier Sense Counter Register (FCSCR), address 0x14 Bit Bit Name Default 15:8 RESERVED 0, RO 7:0 FCSCNT[7:0] 0, RO / COR Description RESERVED: Writes ignored, Read as 0 False Carrier Event Counter: This 8-bit counter increments on every false carrier event. This counter sticks when it reaches its max count (FFh). 7.2.3 Receiver Error Counter Register (RECR) This counter provides information required to implement the “Symbol Error During Carrier” attribute within the PHY managed object class of Clause 30 of the IEEE 802.3u specification. Table 23. Receiver Error Counter Register (RECR), address 0x15 Bit Bit Name Default 15:8 RESERVED 0, RO 7:0 RXERCNT[7:0] 0, RO / COR Description RESERVED: Writes ignored, Read as 0 RX_ER Counter: When a valid carrier is present and there is at least one occurrence of an invalid data symbol, this 8-bit counter increments for each receive error detected. This event can increment only once per valid carrier event. If a collision is present, the attribute will not increment. The counter sticks when it reaches its max count. www.national.com 50 DP83848K 7.2.4 100 Mb/s PCS Configuration and Status Register (PCSR) Table 24. 100 Mb/s PCS Configuration and Status Register (PCSR), address 0x16 Bit Bit Name Default 15:13 RESERVED <00>, RO 12 RESERVED 0 Description RESERVED: Writes ignored, Read as 0. RESERVED: Must be zero. 11 RESERVED 0 10 TQ_EN 0, RW RESERVED: Must be zero. 100Mbs True Quiet Mode Enable: 1 = Transmit True Quiet Mode. 0 = Normal Transmit Mode. 9 SD FORCE PMA 0, RW Signal Detect Force PMA: 1 = Forces Signal Detection in PMA. 0 = Normal SD operation. 8 SD_OPTION 1, RW Signal Detect Option: 1 = Enhanced signal detect algorithm. 0 = Reduced signal detect algorithm. 7 DESC_TIME 0, RW Descrambler Timeout: Increase the descrambler timeout. When set this should allow the device to receive larger packets (>9k bytes) without loss of synchronization. 1 = 2ms 0 = 722us (per ANSI X3.263: 1995 (TP-PMD) 7.2.3.3e) 6 RESERVED 0 RESERVED: Must be zero. 5 FORCE_100_OK 0, RW Force 100Mb/s Good Link: 1 = Forces 100Mb/s Good Link. 0 = Normal 100Mb/s operation. 4 RESERVED 0 RESERVED: Must be zero. 3 RESERVED 0 2 NRZI_BYPASS 0, RW RESERVED: Must be zero. NRZI Bypass Enable: 1 = NRZI Bypass Enabled. 0 = NRZI Bypass Disabled. 1 RESERVED 0 0 RESERVED 0 RESERVED: Must be zero. RESERVED: Must be zero. 51 www.national.com DP83848K 7.2.5 RMII and Bypass Register (RBR) This register configures the RMII Mode of operation. When RMII mode is disabled, the RMII functionality is bypassed. Table 25. RMII and Bypass Register (RBR), addresses 0x17 Bit Bit Name Default 15:6 RESERVED 0, RO 5 RMII_MODE Strap, RW Description RESERVED: Writes ignored, Read as 0. Reduced MII Mode: 0 = Standard MII Mode 1 = Reduced MII Mode 4 RMII_REV1_0 0, RW Reduce MII Revision 1.0: 0 = (RMII revision 1.2) CRS_DV will toggle at the end of a packet to indicate deassertion of CRS. 1 = (RMII revision 1.0) CRS_DV will remain asserted until final data is transferred. CRS_DV will not toggle at the end of a packet. 3 RX_OVF_STS 0, RO RX FIFO Over Flow Status: 0 = Normal 1 = Overflow detected 2 RX_UNF_STS 0, RO RX FIFO Under Flow Status: 0 = Normal 1 = Underflow detected 1:0 ELAST_BUF[1:0] 1, RW Receive Elasticity Buffer. This field controls the Receive Elasticity Buffer which allows for frequency variation tolerance between the 50MHz RMII clock and the recovered data. The following value indicate the tolerance in bits for a single packet. The minimum setting allows for standard Ethernet frame sizes at +/-50ppm accuracy for both RMII and Receive clocks. For greater frequency tolerance the packet lengths may be scaled (i.e. for +/-100ppm, the packet lengths need to be divided by 2). 00 = 14 bit tolerance (up to 16800 byte packets) 01 = 2 bit tolerance (up to 2400 byte packets) 10 = 6 bit tolerance (up to 7200 byte packets) 11 = 10 bit tolerance (up to 12000 byte packets) www.national.com 52 This register provides the ability to directly control the LED outputs. It does not provide read access to the LEDs. Table 26. LED Direct Control Register (LEDCR), address 0x18 Bit Bit Name Default 15:6 RESERVED 0, RO 5 DRV_SPDLED 0, RW Description RESERVED: Writes ignored, read as 0. 1 = Drive value of SPDLED bit onto LED_SPEED output 0 = Normal operation 4 DRV_LNKLED 0, RW 1 = Drive value of LNKLED bit onto LED_LINK output 0 = Normal operation 3 RESERVED 0 RESERVED: 2 SPDLED 0, RW Value to force on LED_SPEED output 1 LNKLED 0, RW Value to force on LED_LINK output 0 RESERVED 0 Must be zero. RESERVED: Must be zero. 53 www.national.com DP83848K 7.2.6 LED Direct Control Register (LEDCR) DP83848K 7.2.7 PHY Control Register (PHYCR) Table 27. PHY Control Register (PHYCR), address 0x19 Bit Bit Name Default 15 MDIX_EN Strap, RW Description Auto-MDIX Enable: 1 = Enable Auto-neg Auto-MDIX capability. 0 = Disable Auto-neg Auto-MDIX capability. The Auto-MDIX algorithm requires that the Auto-Negotiation Enable bit in the BMCR register to be set. If Auto-Negotiation is not enabled, Auto-MDIX should be disabled as well. 14 FORCE_MDIX 0, RW Force MDIX: 1 = Force MDI pairs to cross. (Receive on TPTD pair, Transmit on TPRD pair) 0 = Normal operation. 13 PAUSE_RX 0, RO Pause Receive Negotiated: Indicates that pause receive should be enabled in the MAC. Based on ANAR[11:10] and ANLPAR[11:10] settings. This function shall be enabled according to IEEE 802.3 Annex 28B Table 28B-3, “Pause Resolution”, only if the Auto-Negotiated Highest Common Denominator is a full duplex technology. 12 PAUSE_TX 0, RO Pause Transmit Negotiated: Indicates that pause transmit should be enabled in the MAC. Based on ANAR[11:10] and ANLPAR[11:10] settings. This function shall be enabled according to IEEE 802.3 Annex 28B Table 28B-3, “Pause Resolution”, only if the Auto-Negotiated Highest Common Denominator is a full duplex technology. 11 BIST_FE 0, RW/SC BIST Force Error: 1 = Force BIST Error. 0 = Normal operation. This bit forces a single error, and is self clearing. 10 PSR_15 0, RW BIST Sequence select: 1 = PSR15 selected. 0 = PSR9 selected. 9 BIST_STATUS 0, LL/RO BIST Test Status: 1 = BIST pass. 0 = BIST fail. Latched, cleared when BIST is stopped. For a count number of BIST errors, see the BIST Error Count in the CDCTRL1 register. 8 BIST_START 0, RW BIST Start: 1 = BIST start. 0 = BIST stop. 7 BP_STRETCH 0, RW Bypass LED Stretching: This will bypass the LED stretching and the LEDs will reflect the internal value. 1 = Bypass LED stretching. 0 = Normal operation. 6 www.national.com RESERVED 0 RESERVED: Must be zero. 54 DP83848K Table 27. PHY Control Register (PHYCR), address 0x19 (Continued) Bit Bit Name Default 5 LED_CNFG[0] Strap, RW Description LED Configuration LED_ CNFG[0] Mode Description 1 Mode 1 0 Mode2 In Mode 1, LEDs are configured as follows: LED_LINK = ON for Good Link, OFF for No Link LED_SPEED = ON in 100Mb/s, OFF in 10Mb/s In Mode 2, LEDs are configured as follows: LED_LINK = ON for good Link, BLINK for Activity LED_SPEED = ON in 100Mb/s, OFF in 10Mb/s 4:0 PHYADDR[4:0] Strap, RW PHY Address: PHY address for port. 55 www.national.com DP83848K 7.2.8 10Base-T Status/Control Register (10BTSCR) Table 28. 10Base-T Status/Control Register (10BTSCR), address 0x1A Bit Bit Name Default 15 RESERVED 0, RW Description RESERVED: Must be zero. 14:12 RESERVED 0, RW RESERVED: Must be zero. 11:9 SQUELCH 100, RW Squelch Configuration: Used to set the Squelch ‘ON’ threshold for the receiver. Default Squelch ON is 330mV peak. 8 LOOPBACK_10_D IS 0, RW In half-duplex mode, default 10BASE-T operation loops Transmit data to the Receive data in addition to transmitting the data on the physical medium. This is for consistency with earlier 10BASE2 and 10BASE5 implementations which used a shared medium. Setting this bit disables the loopback function. This bit does not affect loopback due to setting BMCR[14]. 7 LP_DIS 0, RW Normal Link Pulse Disable: 1 = Transmission of NLPs is disabled. 0 = Transmission of NLPs is enabled. 6 FORCE_LINK_10 0, RW Force 10Mb Good Link: 1 = Forced Good 10Mb Link. 0 = Normal Link Status. 5 RESERVED 0, RW RESERVED: Must be zero. 4 POLARITY RO/LH 10Mb Polarity Status: This bit is a duplication of bit 12 in the PHYSTS register. Both bits will be cleared upon a read of 10BTSCR register, but not upon a read of the PHYSTS register. 1 = Inverted Polarity detected. 0 = Correct Polarity detected. 3 RESERVED 0, RW RESERVED: Must be zero. 2 RESERVED 1, RW RESERVED: Must be set to one. 1 HEARTBEAT_DIS 0, RW Heartbeat Disable: This bit only has influence in half-duplex 10Mb mode. 1 = Heartbeat function disabled. 0 = Heartbeat function enabled. When the device is operating at 100Mb or configured for full duplex operation, this bit will be ignored - the heartbeat function is disabled. 0 JABBER_DIS 0, RW Jabber Disable: Applicable only in 10BASE-T. 1 = Jabber function disabled. 0 = Jabber function enabled. www.national.com 56 DP83848K 7.2.9 CD Test and BIST Extensions Register (CDCTRL1) Table 29. CD Test and BIST Extensions Register (CDCTRL1), address 0x1B Bit Bit Name Default 15:8 BIST_ERROR_CO UNT 0, RO 7:6 RESERVED 0, RW 5 BIST_CONT_MOD E 0, RW CDPATTEN_10 0, RW Description BIST ERROR Counter: Counts number of errored data nibbles during Packet BIST. This value will reset when Packet BIST is restarted. The counter sticks when it reaches its max count. RESERVED: Must be zero. 4 Packet BIST Continuous Mode: Allows continuous pseudo random data transmission without any break in transmission. This can be used for transmit VOD testing. This is used in conjunction with the BIST controls in the PHYCR Register (0x19h). For 10Mb operation, jabber function must be disabled, bit 0 of the 10BTSCR (0x1Ah), JABBER_DIS = 1. CD Pattern Enable for 10Mb: 1 = Enabled. 0 = Disabled. 3 RESERVED 0, RW RESERVED: Must be zero. 2 10MEG_PATT_GA P 0, RW Defines gap between data or NLP test sequences: 1 = 15 µs. 0 = 10 µs. 1:0 CDPATTSEL[1:0] 00, RW CD Pattern Select[1:0]: If CDPATTEN_10 = 1: 00 = Data, EOP0 sequence 01 = Data, EOP1 sequence 10 = NLPs 11 = Constant Manchester 1s (10MHz sine wave) for harmonic distortion testing. 57 www.national.com DP83848K 7.2.10 Energy Detect Control (EDCR) Table 30. Energy Detect Control (EDCR), address 0x1D Bit Bit Name Default 15 ED_EN 0, RW Description Energy Detect Enable: Allow Energy Detect Mode. When Energy Detect is enabled and Auto-Negotiation is disabled via the BMCR register, Auto-MDIX should be disabled via the PHYCR register. 14 ED_AUTO_UP 1, RW Energy Detect Automatic Power Up: Automatically begin power up sequence when Energy Detect Data Threshold value (EDCR[3:0]) is reached. Alternatively, device could be powered up manually using the ED_MAN bit (ECDR[12]). 13 ED_AUTO_DOWN 1, RW Energy Detect Automatic Power Down: Automatically begin power down sequence when no energy is detected. Alternatively, device could be powered down using the ED_MAN bit (EDCR[12]). 12 ED_MAN 0, RW/SC Energy Detect Manual Power Up/Down: Begin power up/down sequence when this bit is asserted. When set, the Energy Detect algorithm will initiate a change of Energy Detect state regardless of threshold (error or data) and timer values. 11 ED_BURST_DIS 0, RW Energy Detect Bust Disable: Disable bursting of energy detect data pulses. By default, Energy Detect (ED) transmits a burst of 4 ED data pulses each time the CD is powered up. When bursting is disabled, only a single ED data pulse will be send each time the CD is powered up. 10 ED_PWR_STATE 0, RO Energy Detect Power State: Indicates current Energy Detect Power state. When set, Energy Detect is in the powered up state. When cleared, Energy Detect is in the powered down state. This bit is invalid when Energy Detect is not enabled. 9 ED_ERR_MET 0, RO/COR Energy Detect Error Threshold Met: No action is automatically taken upon receipt of error events. This bit is informational only and would be cleared on a read. 8 ED_DATA_MET 0, RO/COR Energy Detect Data Threshold Met: The number of data events that occurred met or surpassed the Energy Detect Data Threshold. This bit is cleared on a read. 7:4 ED_ERR_COUNT 0001, RW Energy Detect Error Threshold: Threshold to determine the number of energy detect error events that should cause the device to take action. Intended to allow averaging of noise that may be on the line. Counter will reset after approximately 2 seconds without any energy detect data events. 3:0 ED_DATA_COUNT 0001, RW Energy Detect Data Threshold: Threshold to determine the number of energy detect events that should cause the device to take actions. Intended to allow averaging of noise that may be on the line. Counter will reset after approximately 2 seconds without any energy detect data events. www.national.com 58 DP83848K 8.0 Electrical Specifications Note: All parameters are guaranteed by test, statistical analysis or design. Absolute Maximum Ratings Recommended Operating Conditions Supply Voltage (VCC) Supply voltage (VCC) -0.5 V to 4.2 V 3.3 Volts + .3V DC Input Voltage (VIN) -0.5V to VCC + 0.5V Industrial - Ambient Temperature (TA) DC Output Voltage (VOUT) -0.5V to VCC + 0.5V Power Dissipation (PD) Storage Temperature (TSTG) 147.7 °C Max. die temperature (Tj) 150 °C Lead Temp. (TL) (Soldering, 10 sec.) 260 °C ESD Rating (RZAP = 1.5k, CZAP = 120 pF) 4.0 kV 264 mW Absolute maximum ratings are those values beyond which the safety of the device cannot be guaranteed. They are not meant to imply that the device should be operated at these limits. -65oC to 150°C Max case temp -40°C to 85°C Thermal Characteristic Max Units Theta Junction to Case (Tjc) 8.8 °C / W Theta Junction to Ambient (Tja) degrees Celsius/Watt - No Airflow @ 1.0W 31.7 °C / W Note: This is done with a JEDEC (2 layer 2 oz CU.) thermal test board 8.1 DC SPECS Symbol Pin Types Parameter Conditions Min Typ Max Units VIH I I/O Input High Voltage Nominal VCC VIL I I/O Input Low Voltage 0.8 V IIH I I/O Input High Current VIN = VCC 10 µA IIL I I/O Input Low Current VIN = GND 10 µA VOL O, I/O Output Low Voltage IOL = 4 mA 0.4 V VOH O, I/O Output High Voltage IOH = -4 mA VledOL LED Output Low Voltage IOL = 2.5 mA VledOH LED Output High Voltage IOH = -2.5 mA IOZ I/O, O TRI-STATE Leakage VOUT = VCC VTPTD_100 PMD Output Pair 100M Transmit Voltage VTPTDsym PMD Output Pair 100M Transmit Voltage Symmetry VTPTD_10 PMD Output Pair 10M Transmit Voltage 2.0 Vcc - 0.5 V 0.4 Vcc - 0.5 0.95 2.2 59 V V V 1 2.5 + 10 µA 1.05 V +2 % 2.8 V www.national.com DP83848K Symbol Pin Types Parameter Conditions Min Typ Max Units CIN1 I CMOS Input Capacitance 5 pF COUT1 O CMOS Output Capacitance 5 pF SDTHon PMD Input Pair 100BASE-TX Signal detect turnon threshold SDTHoff PMD Input Pair 100BASE-TX Signal detect turnoff threshold VTH1 PMD Input Pair 10BASE-T Receive Threshold Idd100 Supply Idd10 Supply 1000 200 mV diff pk-pk 585 100BASE-TX (Full Duplex) IOUT = 0 mA 10BASE-T (Full Duplex) IOUT = 0 mA mV 81 mA 92 mA See Note 1 See Note 1 1. Refer to application note AN-1540, “Power Measurement of Ethernet Physical Layer Products” www.national.com mV diff pk-pk 60 DP83848K 8.2 AC SPECS 8.2.1 Power Up Timing Vcc X1 clock T2.1.1 Hardware RESET_N 32 clocks MDC T2.1.2 Latch-In of Hardware Configuration Pins T2.1.3 input Dual Function Pins Become Enabled As Outputs Parameter Description output Notes Min Typ Max Units T2.1.1 MDIO is pulled high for 32-bit serial manPost Power Up Stabilization time prior to MDC preamble for agement initialization register accesses X1 Clock must be stable for a min. of 167ms at power up. 167 ms T2.1.2 Hardware Configuration Latch- Hardware Configuration Pins are dein Time from power up scribed in the Pin Description section 167 ms X1 Clock must be stable for a min. of 167ms at power up. T2.1.3 Hardware Configuration pins transition to output drivers 50 ns Note: In RMII Mode, the minimum Post Power up Stabilization and Hardware Configuration Latch-in times are 84 ms. 61 www.national.com DP83848K 8.2.2 Reset Timing Vcc X1 clock T2.2.4 T2.2.1 Hardware RESET_N 32 clocks MDC T2.2.2 Latch-In of Hardware Configuration Pins T2.2.3 input output Dual Function Pins Become Enabled As Outputs Parameter Description Notes Min Typ Max Units T2.2.1 Post RESET Stabilization time MDIO is pulled high for 32-bit serial manprior to MDC preamble for reg- agement initialization ister accesses 3 µs T2.2.2 Hardware Configuration Latch- Hardware Configuration Pins are dein Time from the Deassertion scribed in the Pin Description section of RESET (either soft or hard) 3 µs T2.2.3 Hardware Configuration pins transition to output drivers 50 ns T2.2.4 RESET pulse width X1 Clock must be stable for at min. of 1us during RESET pulse low time. 1 µs Note: It is important to choose pull-up and/or pull-down resistors for each of the hardware configuration pins that provide fast RC time constants in order to latch-in the proper value prior to the pin transitioning to an output driver. www.national.com 62 DP83848K 8.2.3 MII Serial Management Timing MDC T2.3.1 T2.3.4 MDIO (output) MDC T2.3.2 Valid Data MDIO (input) Parameter T2.3.3 Description Notes Min T2.3.1 MDC to MDIO (Output) Delay Time 0 T2.3.2 MDIO (Input) to MDC Setup Time 10 T2.3.3 MDIO (Input) to MDC Hold Time 10 T2.3.4 MDC Frequency Typ Max Units 30 ns ns ns 2.5 25 MHz 8.2.4 100 Mb/s MII Transmit Timing T2.4.1 T2.4.1 TX_CLK T2.4.2 TXD[3:0] TX_EN Parameter T2.4.3 Valid Data Description Notes Min Typ 20 Max Units T2.4.1 TX_CLK High/Low Time 100 Mb/s Normal mode 16 T2.4.2 TXD[3:0], TX_EN Data Setup to TX_CLK 100 Mb/s Normal mode 10 ns T2.4.3 TXD[3:0], TX_EN Data Hold from TX_CLK 100 Mb/s Normal mode 0 ns 63 24 ns www.national.com DP83848K 8.2.5 100 Mb/s MII Receive Timing T2.5.1 T2.5.1 RX_CLK T2.5.2 RXD[3:0] RX_DV RX_ER Valid Data Min Typ Max Units T2.5.1 Parameter RX_CLK High/Low Time Description 100 Mb/s Normal mode Notes 16 20 24 ns T2.5.2 RX_CLK to RXD[3:0], RX_DV, RX_ER Delay 100 Mb/s Normal mode 10 30 ns Note: RX_CLK may be held low or high for a longer period of time during transition between reference and recovered clocks. Minimum high and low times will not be violated. 8.2.6 100BASE-TX Transmit Packet Latency Timing TX_CLK TX_EN TXD PMD Output Pair Parameter T2.6.1 T2.6.1 IDLE (J/K) Description TX_CLK to PMD Output Pair Latency Notes 100 Mb/s Normal mode DATA Min Typ 6 Max Units bits Note: For Normal mode, latency is determined by measuring the time from the first rising edge of TX_CLK occurring after the assertion of TX_EN to the first bit of the “J” code group as output from the PMD Output Pair. 1 bit time = 10 ns in 100 Mb/s mode. www.national.com 64 DP83848K 8.2.7 100BASE-TX Transmit Packet Deassertion Timing TX_CLK TX_EN TXD T2.7.1 PMD Output Pair Parameter T2.7.1 DATA DATA (T/R) (T/R) Description TX_CLK to PMD Output Pair Deassertion Notes 100 Mb/s Normal mode IDLE IDLE Min Typ 6 Max Units bits Note: Deassertion is determined by measuring the time from the first rising edge of TX_CLK occurring after the deassertion of TX_EN to the first bit of the “T” code group as output from the PMD Output Pair. 1 bit time = 10 ns in 100 Mb/s mode. 65 www.national.com DP83848K 8.2.8 100BASE-TX Transmit Timing (tR/F & Jitter) T2.8.1 +1 rise 90% 10% PMD Output Pair 10% +1 fall 90% T2.8.1 -1 fall -1 rise T2.8.1 T2.8.1 T2.8.2 PMD Output Pair eye pattern Parameter T2.8.1 T2.8.2 T2.8.2 Description Notes Min Typ Max Units 3 4 5 ns 100 Mb/s tR and tF Mismatch 500 ps 100 Mb/s PMD Output Pair Transmit Jitter 1.4 ns 100 Mb/s PMD Output Pair tR and tF Note: Normal Mismatch is the difference between the maximum and minimum of all rise and fall times Note: Rise and fall times taken at 10% and 90% of the +1 or -1 amplitude www.national.com 66 DP83848K 8.2.9 100BASE-TX Receive Packet Latency Timing PMD Input Pair IDLE Data (J/K) T2.9.1 CRS T2.9.2 RXD[3:0] RX_DV RX_ER Parameter Description Notes Min Typ Max Units T2.9.1 Carrier Sense ON Delay 100 Mb/s Normal mode 20 bits T2.9.2 Receive Data Latency 100 Mb/s Normal mode 24 bits Note: Carrier Sense On Delay is determined by measuring the time from the first bit of the “J” code group to the assertion of Carrier Sense. Note: 1 bit time = 10 ns in 100 Mb/s mode Note: PMD Input Pair voltage amplitude is greater than the Signal Detect Turn-On Threshold Value. 8.2.10 100BASE-TX Receive Packet Deassertion Timing PMD Input Pair DATA IDLE (T/R) T2.10.1 CRS Parameter T2.10.1 Description Carrier Sense OFF Delay Notes 100 Mb/s Normal mode Min Typ 24 Max Units bits Note: Carrier Sense Off Delay is determined by measuring the time from the first bit of the “T” code group to the deassertion of Carrier Sense. Note: 1 bit time = 10 ns in 100 Mb/s mode 67 www.national.com DP83848K 8.2.11 10 Mb/s MII Transmit Timing T2.11.1 T2.11.1 TX_CLK T2.11.2 TXD[3:0] TX_EN Parameter T2.11.3 Valid Data Description Notes Min Typ Max Units 200 210 T2.11.1 TX_CLK High/Low Time 10 Mb/s MII mode 190 ns T2.11.2 TXD[3:0], TX_EN Data Setup to TX_CLK fall 10 Mb/s MII mode 25 ns T2.11.3 TXD[3:0], TX_EN Data Hold from TX_CLK rise 10 Mb/s MII mode 0 ns Note: An attached Mac should drive the transmit signals using the positive edge of TX_CLK. As shown above, the MII signals are sampled on the falling edge of TX_CLK. 8.2.12 10 Mb/s MII Receive Timing T2.12.1 T2.12.1 RX_CLK T2.12.2 RXD[3:0] RX_DV Parameter T2.12.3 Valid Data Description Notes Min Typ Max Units 160 200 240 ns T2.12.1 RX_CLK High/Low Time T2.12.2 RX_CLK to RXD[3:0], RX_DV Delay 10 Mb/s MII mode 100 ns T2.12.3 RX_CLK rising edge delay from RXD[3:0], RX_DV Valid 10 Mb/s MII mode 100 ns Note: RX_CLK may be held low for a longer period of time during transition between reference and recovered clocks. Minimum high and low times will not be violated. www.national.com 68 DP83848K 8.2.13 10BASE-T Transmit Timing (Start of Packet) TX_CLK TX_EN TXD PMD Output Pair T2.13.1 Parameter T2.13.1 Description Notes Transmit Output Delay from the Min 10 Mb/s MII mode Typ Max 3.5 Units bits Falling Edge of TX_CLK Note: 1 bit time = 100 ns in 10Mb/s. 8.2.14 10BASE-T Transmit Timing (End of Packet) TX_CLK TX_EN 0 PMD Output Pair T2.14.1 0 T2.14.2 PMD Output Pair Parameter T2.14.1 1 1 Description Notes End of Packet High Time Min Typ Max Units 250 300 ns 250 300 ns (with ‘0’ ending bit) T2.14.2 End of Packet High Time (with ‘1’ ending bit) 69 www.national.com DP83848K 8.2.15 10BASE-T Receive Timing (Start of Packet) 1st SFD bit decoded 1 0 1 0 1 0 1 0 1 0 1 1 TPRD± T2.15.1 CRS RX_CLK T2.15.2 RX_DV T2.15.3 0000 RXD[3:0] Parameter Preamble Description SFD Notes Min Data Typ Max Units 1000 ns T2.15.1 Carrier Sense Turn On Delay (PMD Input Pair to CRS) 630 T2.15.2 RX_DV Latency 10 bits T2.15.3 Receive Data Latency 8 bits Measurement shown from SFD Note: 10BASE-T RX_DV Latency is measured from first bit of preamble on the wire to the assertion of RX_DV Note: 1 bit time = 100 ns in 10 Mb/s mode. 8.2.16 10BASE-T Receive Timing (End of Packet) 1 0 1 IDLE PMD Input Pair RX_CLK T2.16.1 CRS Parameter T2.16.1 Description Notes Carrier Sense Turn Off Delay www.national.com 70 Min Typ Max Units 1.0 µs DP83848K 8.2.17 10 Mb/s Heartbeat Timing TX_EN TX_CLK T2.17.1 T2.17.2 COL Parameter Description Notes Min Typ Max Units T2.17.1 CD Heartbeat Delay All 10 Mb/s modes 1200 ns T2.17.2 CD Heartbeat Duration All 10 Mb/s modes 1000 ns 8.2.18 10 Mb/s Jabber Timing TXE T2.18.1 T2.18.2 PMD Output Pair COL Parameter Description Notes Min Typ Max Units T2.18.1 Jabber Activation Time 85 ms T2.18.2 Jabber Deactivation Time 500 ms 71 www.national.com DP83848K 8.2.19 10BASE-T Normal Link Pulse Timing T2.19.2 T2.19.1 Normal Link Pulse(s) Parameter Description Notes Min Typ Max Units T2.19.1 Pulse Width 100 ns T2.19.2 Pulse Period 16 ms Note: These specifications represent transmit timings. 8.2.20 Auto-Negotiation Fast Link Pulse (FLP) Timing T2.20.2 T2.20.3 T2.20.1 T2.20.1 Fast Link Pulse(s) clock pulse data pulse clock pulse T2.20.5 T2.20.4 FLP Burst Parameter FLP Burst Description Notes Min Typ Max Units T2.20.1 Clock, Data Pulse Width 100 ns T2.20.2 Clock Pulse to Clock Pulse Period 125 µs T2.20.3 Clock Pulse to Data Pulse Period 62 µs T2.20.4 Burst Width 2 ms T2.20.5 FLP Burst to FLP Burst Period 16 ms Data = 1 Note: These specifications represent transmit timings. www.national.com 72 DP83848K 8.2.21 100BASE-TX Signal Detect Timing PMD Input Pair T2.21.1 T2.21.2 SD+ internal Parameter Description Notes Min Typ Max Units T2.21.1 SD Internal Turn-on Time 1 ms T2.21.2 SD Internal Turn-off Time 350 µs Max Units 240 ns Note: The signal amplitude on PMD Input Pair must be TP-PMD compliant. 8.2.22 100 Mb/s Internal Loopback Timing TX_CLK TX_EN TXD[3:0] CRS T2.22.1 RX_CLK RX_DV RXD[3:0] Parameter T2.22.1 Description TX_EN to RX_DV Loopback Notes Min 100 Mb/s internal loopback mode Typ Note: Due to the nature of the descrambler function, all 100BASE-TX Loopback modes will cause an initial “dead-time” of up to 550 µs during which time no data will be present at the receive MII outputs. The 100BASE-TX timing specified is based on device delays after the initial 550µs “dead-time”. Note: Measurement is made from the first rising edge of TX_CLK after assertion of TX_EN. 73 www.national.com DP83848K 8.2.23 10 Mb/s Internal Loopback Timing TX_CLK TX_EN TXD[3:0] CRS T2.23.1 RX_CLK RX_DV RXD[3:0] Parameter T2.23.1 Description TX_EN to RX_DV Loopback Notes Min 10 Mb/s internal loopback mode Note: Measurement is made from the first rising edge of TX_CLK after assertion of TX_EN. www.national.com 74 Typ Max Units 2 µs DP83848K 8.2.24 RMII Transmit Timing T2.24.1 X1 T2.24.2 TXD[1:0] TX_EN T2.24.3 Valid Data T2.24.4 PMD Output Pair Parameter Symbol Description Notes Min 50 MHz Reference Clock Typ T2.24.1 X1 Clock Period T2.24.2 TXD[1:0], TX_EN, Data Setup to X1 rising 4 ns T2.24.3 TXD[1:0], TX_EN, Data Hold from X1 rising 2 ns T2.24.4 X1 Clock to PMD Output Pair From X1 Rising edge to first bit of symbol Latency 75 20 Max Units 17 ns bits www.national.com DP83848K 8.2.25 RMII Receive Timing PMD Input Pair IDLE (J/K) Data Data (TR) T2.25.4 T2.25.5 X1 T2.25.1 T2.25.2 T2.25.2 T2.25.3 T2.25.2 RX_DV CRS_DV T2.25.2 RXD[1:0] RX_ER Parameter Description Notes Min 50 MHz Reference Clock Typ Max 20 Units T2.25.1 X1 Clock Period T2.25.2 RXD[1:0], CRS_DV, RX_DV, and RX_ER output delay from X1 rising T2.25.3 CRS ON delay From JK symbol on PMD Receive Pair to initial assertion of CRS_DV 18.5 bits T2.25.4 CRS OFF delay From TR symbol on PMD Receive Pair to initial deassertion of CRS_DV 27 bits T2.25.5 RXD[1:0] and RX_ER latency From symbol on Receive Pair. Elasticity buffer set to default value (01) 38 bits 2 ns 14 ns Note: Per the RMII Specification, output delays assume a 25pF load. Note: CRS_DV is asserted asynchronously in order to minimize latency of control signals through the Phy. CRS_DV may toggle synchronously at the end of the packet to indicate CRS deassertion. Note: RX_DV is synchronous to X1. While not part of the RMII specification, this signal is provided to simplify recovery of receive data. Note: CRS ON delay is measured from the first bit of the JK symbol on the PMD Input Pair to initial assertion of CRS_DV. Note: CRS OFF delay is measured from the first bit of the TR symbol on the PMD Input Pair to initial de-assertion of CRS_DV. Note: Receive Latency is measured from the first bit of the symbol pair on the PMD Input Pair. Typical values are with the Elasticity Buffer set to the default value (01). www.national.com 76 DP83848K 8.2.26 Isolation Timing Clear bit 10 of BMCR (return to normal operation from Isolate mode) T2.26.1 H/W or S/W Reset (with PHYAD = 00000) T2.26.2 MODE NORMAL ISOLATE Max Units T2.26.1 Parameter From software clear of bit 10 in the BMCR register to the transition from Isolate to Normal Mode Description Notes Min Typ 100 µs T2.26.2 From Deassertion of S/W or H/W Reset to transition from Isolate to Normal mode 500 µs Max Units 5 ns 8.2.27 100 Mb/s X1 to TX_CLK Timing X1 T2.27.1 TX_CLK Parameter T2.27.1 Description Notes X1 to TX_CLK delay 100 Mb/s Normal mode Min 0 Typ Note: X1 to TX_CLK timing is provided to support devices that use X1 instead of TX_CLK as the reference for transmit Mll data. 77 www.national.com DP83848K PHYTERR Mini LS - Single Port 10/100 Mb/s Ethernet Physical Layer Transceiver Physical Dimensions inches (millimeters) unless otherwise noted THE CONTENTS OF THIS DOCUMENT ARE PROVIDED IN CONNECTION WITH NATIONAL SEMICONDUCTOR CORPORATION (“NATIONAL”) PROCUCTS. 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