Pin Description | NVIDIA BlueField-2 Ethernet DPU User Guide

PCI Express Interface

DPU PCI Express x8 Pin Description

Pin #	Signal Name	Description	Pin #	Signal Name	Description
A1	PRSNT1#	Mechanical Present	B1	12V
A2	12V		B2	12V
A3	12V		B3	12V
A4	GND		B4	GND
A5	TCK	JTAG - Not Connected	B5	SMCLK	Host SMBus
A6	TDI	JTAG - Not Connected	B6	SMDAT	Host SMBus
A7	TDO	JTAG - Not Connected	B7	GND
A8	TMS	JTAG - Not Connected	B8	3.3V	3.3V - Not Connected
A9	3.3V	3.3V - Not Connected	B9	TRST#	JTAG - Not Connected
A10	3.3V	3.3V - Not Connected	B10	3.3V_AUX
A11	PERST#	PCIe Reset	B11	WAKE#/RSVD
A12	GND		B12	RSVD
A13	REFCLK+	Host Reference Clock	B13	GND
A14	REFCLK-	Host Reference Clock	B14	PETP0
A15	GND		B15	PETN0
A16	PERP0		B16	GND
A17	PERN0		B17	RSVD
A18	GND		B18	GND
A19	RSVD		B19	PETP1
A20	GND		B20	PETN1
A21	PERP1		B21	GND
A22	PERN1		B22	GND
A23	GND		B23	PETP2
A24	GND		B24	PETN2
A25	PERP2		B25	GND
A26	PERN2		B26	GND
A27	GND		B27	PETP3
A28	GND		B28	PETN3
A29	PERP3		B29	GND
A30	PERN3		B30	RSVD
A31	GND		B31	RSVD
A32	RSVD		B32	GND
A33	RSVD		B33	PETP4
A34	GND		B34	PETN4
A35	PERP4		B35	GND
A36	PERN4		B36	GND
A37	GND		B37	PETP5
A38	GND		B38	PETN5
A39	PERP5		B39	GND
A40	PERN5		B40	GND
A41	GND		B41	PETP6
A42	GND		B42	PETN6
A43	PERP6		B43	GND
A44	PERN6		B44	GND
A45	GND		B45	PETP7
A46	GND		B46	PETN7
A47	PERP7		B47	GND
A48	PERN7		B48	PRSNT2#	Mechanical Present
A49	GND		B49	GND

DPU PCI Express x16 Pin Description

Pin #	Signal Name	Description	Pin #	Signal Name	Description
A1	PRSNT1#	Mechanical Present	B1	12V
A2	12V		B2	12V
A3	12V		B3	12V
A4	GND		B4	GND
A5	TCK	JTAG - Not Connected	B5	SMCLK	Host SMBus
A6	TDI	JTAG - Not Connected	B6	SMDAT	Host SMBus
A7	TDO	JTAG - Not Connected	B7	GND
A8	TMS	JTAG - Not Connected	B8	3.3V	3.3V - Not Connected
A9	3.3V	3.3V - Not Connected	B9	TRST#	JTAG - Not Connected
A10	3.3V	3.3V - Not Connected	B10	3.3V_AUX
A11	PERST#	PCIe Reset	B11	WAKE#/RSVD
A12	GND		B12	RSVD
A13	REFCLK+	Host Reference Clock	B13	GND
A14	REFCLK-	Host Reference Clock	B14	PETP0
A15	GND		B15	PETN0
A16	PERP0		B16	GND
A17	PERN0		B17	RSVD
A18	GND		B18	GND
A19	RSVD		B19	PETP1
A20	GND		B20	PETN1
A21	PERP1		B21	GND
A22	PERN1		B22	GND
A23	GND		B23	PETP2
A24	GND		B24	PETN2
A25	PERP2		B25	GND
A26	PERN2		B26	GND
A27	GND		B27	PETP3
A28	GND		B28	PETN3
A29	PERP3		B29	GND
A30	PERN3		B30	RSVD
A31	GND		B31	RSVD
A32	RSVD		B32	GND
A33	RSVD		B33	PETP4
A34	GND		B34	PETN4
A35	PERP4		B35	GND
A36	PERN4		B36	GND
A37	GND		B37	PETP5
A38	GND		B38	PETN5
A39	PERP5		B39	GND
A40	PERN5		B40	GND
A41	GND		B41	PETP6
A42	GND		B42	PETN6
A43	PERP6		B43	GND
A44	PERN6		B44	GND
A45	GND		B45	PETP7
A46	GND		B46	PETN7
A47	PERP7		B47	GND
A48	PERN7		B48	RSVD
A49	GND		B49	GND
A50	RSVD		B50	PETP8
A51	GND		B51	PETN8
A52	PERP8		B52	GND
A53	PERN8		B53	GND
A54	GND		B54	PETP9
A55	GND		B55	PETN9
A56	PERP9		B56	GND
A57	PERN9		B57	GND
A58	GND		B58	PETP10
A59	GND		B59	PETN10
A60	PERP10		B60	GND
A61	PERN10		B61	GND
A62	GND		B62	PETP11
A63	GND		B63	PETN11
A64	PERP11		B64	GND
A65	PERN11		B65	GND
A66	GND		B66	PETP12
A67	GND		B67	PETN12
A68	PERP12		B68	GND
A69	PERN12		B69	GND
A70	GND		B70	PETP13
A71	GND		B71	PETN13
A72	PERP13		B72	GND
A73	PERN13		B73	GND
A74	GND		B74	PETP14
A75	GND		B75	PETN14
A76	PERP14		B76	GND
A77	PERN14		B77	GND
A78	GND		B78	PETP15
A79	GND		B79	PETN15
A80	PERP15		B80	GND
A81	PERN15		B81	PRSNT2#	Mechanical Present
A82	GND		B82	RSVD

External Power Supply Connector

The below table provides the External Power Supply pins of the external power supply interfaces on the DPU. For further details, please refer to External PCIe Power Supply Connector.

The mechanical pinout of the 6-pin external +12V power connector is shown below. The +12V connector is a GPU power PCIe standard connector. Care should be taken to ensure the power is applied to the correct pins as some 6-pin ATX type connector can have different pinouts.

Pin#	Signal Name	Description
1	12V	ATX Supplied 12V
2	12V	ATX Supplied 12V
3	12V	ATX Supplied 12V
4	GND	Power Return
5	GND	Power Return
6	GND	Power Return

4-pin Vertical USB Connector

The below table provides the 4-pin vertical USB connector on the DPU. For further details, please refer to USB Interface.

Pin #	Signal
1	+5V_USB
2	USB DP
3	USB DN
4	GND

NC-SI Management Interface

The below tables list the NC-SI management interface pinout descriptions per card type. Please follow the link to the table coinciding with the OPN you have purchased.

OPNs	HW Versions	Link
MBF2H332A-AECOT, MBF2H332A-AECOT, MBF2H332A-AENOT	A1xx - A3xx	30-pin Connector: Pin Description \| id (2.3)PinDescription TableA NC SIConnectorPins
MBF2H332A-AECOT, MBF2H332A-AECOT, MBF2H332A-AENOT	B1xx and Up	30-pin Connector: Pin Description \| id (2.3)PinDescription TableB NC SIConnectorPins
MBF2M355A-VECOT, MBF2M355A-VESOT	A1xx and Up
MBF2H516A-CEEOT, MBF2H516A-CENOT MBF2M516A-CECOT, MBF2M516A-CEEOT MBF2M516A-CENOT, MBF2H512C-AECOT MBF2H516C-CECOT, MBF2H516C-CESOT MBF2H516C-CEUOT, MBF2M516C-CECOT MBF2M516C-CESOT, MBF2H512C-AESOT MBF2H512C-AEUOT	A1xx and Up	30-pin Connector: Pin Description \| id (2.3)PinDescription TableC NC SIConnectorPins
MBF2H532C-AECOT, MBF2H532C-AESOT	A1xx - A5xx
MBF2H536C-CECOT, MBF2H536C-CESOT	A1xx - A7xx
MBF2H532C-AECOT, MBF2H532C-AESOT MBF2H536C-CECOT, MBF2H536C-CESOT	B1xx and Up	20-pin Connector Pin Description \| id (2.3)PinDescription TableD NC SIConnectorPins
MBF2H536C-CEUOT	A1xx and Up

Table A - NC-SI Connector Pins

Pin#	Signal Name	I/O	Description	Comments
1	REF_CLK	Input	50M REF CLK for NCSI BUS	RBT Reference clock. Synchronous clock reference for receive, transmit and control interface. The clock shall have a typical frequency of 50MHz ±50 ppm. For baseboards, this pin shall be connected between the baseboard NC-SI over RBT PHY and the DPU cable connector. The RBT_REF_CLK shall not be driven until 3.3V AUX is present on the DPU. The RBT_REF_CLK shall be continuous once it has started. For DPUs, this pin shall be connected between the connector and the RBT PHY. No external termination is required.
2	GND	GND	Ground
3	ARB_IN	Input	NCSI hardware arbitration input	NC-SI hardware arbitration input If the baseboard supports multiple DPU cards connected to the same RBT interface, it shall implement logic that connects the RBT_ARB_IN pin of the first populated DPU card to its RBT_ARB_OUT pin if it is the only card present or to the RBT_ARB_OUT pin of the next populated card and so on sequentially for all cards on the specified RBT bus to ensure the arbitration ring is complete. This logic shall bypass slots that are not populated or powered off.
4	GND	GND	Ground
5	ARB_OUT	Output	NCSI hardware arbitration output	NC-SI hardware arbitration output. If the baseboard supports multiple DPU cards connected to the same RBT interface, it shall implement logic that connects the RBT_ARB_OUT pin of the first populated DPU card to its RBT_ARB_IN pin if it is the only card present or to the RBT_ARB_IN pin of the next populated card and so on sequentially for all cards on the specified RBT bus to ensure the arbitration ring is complete. This logic shall bypass slots that are not populated or powered off.
6	GND	GND	Ground
7	RX_D0	Output	Receive data	Output for SoC Receive data. Data signals from the network controller to the BMC. For baseboards, this pin shall be connected between the baseboard NC-SI over RBT PHY and the connector. This signal requires a 100 kΩ pull down resistor to GND on the baseboard between the BMC and the RBT isolator to prevent the signal from floating when no card is installed. For DPUs, this pin shall be connected between the connector and the RBT PHY. External termination determined by the DPU RBT PHY requirements.
8	GND	GND	Ground
9	RX_D1	Output	Receive data	Output for SoC Receive data. Data signals from the network controller to the BMC. For baseboards, this pin shall be connected between the baseboard NC-SI over RBT PHY and the connector. This signal requires a 100 kΩ pull down resistor to GND on the baseboard between the BMC and the RBT isolator to prevent the signal from floating when no card is installed. For DPUs, this pin shall be connected between the connector and the RBT PHY. External termination determined by the DPU RBT PHY requirements.
10	GND	GND	Ground
11	CRS_DV	Output	Carrier sense/Receive Data Valid	Carrier sense/receive data valid. This signal is used to indicate to the baseboard that the carrier sense/receive data is valid. For baseboards, this pin shall be connected between the baseboard NC-SI over RBT PHY and the connector. This signal requires a 100 kΩ pull down resistor on the baseboard between the BMC and the RBT isolator to prevent the signal from floating when no DPU is installed. For DPUs, this pin shall be connected between the connector and the RBT PHY. External termination determined by the SmartNIC RBT PHY requirements.
12	GND	GND	Ground
13	TX_D0	Input	Transmit data	Input for SoC. Data signals from the BMC to the network controller. For baseboards, this pin shall be connected between the baseboard NC-SI over RBT PHY and the connector. This signal requires a 100 kΩ pull down resistor to GND on the baseboard between the RBT isolator and the DPUcable connector to prevent the card-side signals from floating when the RBT signals are isolated. For DPUs, this pin shall be connected between the connector and the RBT PHY. External termination determined by the DPU RBT PHY requirements.
14	GND	GND	Ground
15	TX_D1	Input	Transmit data	Input for SoC. Data signals from the BMC to the network controller. For baseboards, this pin shall be connected between the baseboard NC-SI over RBT PHY and the connector. This signal requires a 100 kΩ pull down resistor to GND on the baseboard between the RBT isolator and the DPUcable connector to prevent the card-side signals from floating when the RBT signals are isolated. For DPUs, this pin shall be connected between the connector and the RBT PHY. External termination determined by the DPU RBT PHY requirements.
16	GND	GND	Ground
17	TX_EN	Input	Transmit enable	Transmit enable. For baseboards, this pin shall be connected between the baseboard NC-SI over RBT PHY and the connector. This signal requires a 100 kΩ pull down resistor to ground on the baseboard between the RBT isolator and the DPU cable connector to prevent the card-side signals from floating when the RBT signals are isolated. For DPUs, this pin shall be connected between the connector and the RBT PHY. External termination determined by the DPU RBT PHY requirements.
18	GND	GND	Ground
19	NC
20	NC
21	I2C_SDA	Bidirectional	I2C Serial Data	GW_ARM1
22	GND	GND	Ground
23	I2C_SCL	Bidirectional	I2C Serial Clock	GW_ARM1
24	GND	GND	Ground
25	GND	GND	Ground
26	GND	GND	Ground
27	NC
28	UART_TX	Output	Transmit data	Output for SoC. 3.3V UART TX signal from the baseboard.
29	NC
30	UART_RX	Input	Receive data	3.3V UART RX signal to the baseboard.

Table B - NC-SI Connector Pins

PACK_ID[2:0] signals allow for 8 unique card IDs. The system configurator sets the unique value per card via the connecting harness.

Pin #	Pin Name	I/O	Description / Comments
1	NCSI_REF_CLK	Input	50MHz REF CLK for NC-SI BUS
2	GND	GND	Ground
3	NCSI_ARB_IN	Input	NC-SI hardware arbitration input
4	PACK_ID0, connected to BlueField-2 NIC_GPIO[49]	Input	See the note above table
5	NCSI_ARB_OUT	Output	NC-SI hardware arbitration output
6	PACK_ID1, connected to BlueField-2 NIC_GPIO[47]	Input	See the note above table
7	NCSI_RX_D0	Output	Receive Data Out 0
8	GND	GND	Ground
9	NCSI_RX_D1	Output	Receive Data Out 1
10	GND	GND	Ground
11	NCSI_CRS_DV	Output	Carrier Sense / Receive Data Valid
12	GND	GND	Ground
13	NCSI_TX_D0	Input	Transmit Data In 0
14	GND	GND	Ground
15	NCSI_TX_D1	Input	Transmit Data In 0
16	GND	GND	Ground
17	NCSI_TX_EN	Input	Transmit Enable
18	GND	GND	Ground
19	Reserved
20	SOFT_RST#, connected to BlueField-2 device pin HOST_GPIO[7]
21	ARM_I2C1_SDA	Input/Output	Open-drain signal
22	ARM_NSRST#	Input/Output	Open-drain signal
23	ARM_I2C1_SCL	Input/Output	Open-drain signal
24	PACK_ID2, connected to BlueField-2 device pin NIC_GPIO[46]	Input	See description above table
25	GND	GND	Ground
26	Not Connected
27	Not Connected
28	BF_UART0_TX	Output	UART transmit serial data output
29	Not Connected
30	BF_UART0_RX	Input	UART transmit serial data input

Table C - NC-SI Connector Pins

PACK_ID[2:0] signals allow for 8 unique card IDs. The system configurator sets the unique value per card via the connecting harness.

Pin #	Pin Name	I/O	Description / Comments
1	NCSI_REF_CLK	Input	50MHz REF CLK for NC-SI BUS
2	GND	GND	Ground
3	NCSI_ARB_IN	Input	NC-SI hardware arbitration input
4	PACK_ID0, connected to BlueField-2 device pin NIC_GPIO[49]	Input	See the note above table
5	NCSI_ARB_OUT	Output	NC-SI hardware arbitration output
6	PACK_ID1, connected to BlueField-2 device pin NIC_GPIO[47]	Input	See the note above table
7	NCSI_RX_D0	Output	Receive Data Out 0
8	GND	GND	Ground
9	NCSI_RX_D1	Output	Receive Data Out 1
10	GND	GND	Ground
11	NCSI_CRS_DV	Output	Carrier Sense / Receive Data Valid
12	GND	GND	Ground
13	NCSI_TX_D0	Input	Transmit Data In 0
14	GND	GND	Ground
15	NCSI_TX_D1	Input	Transmit Data In 0
16	GND	GND	Ground
17	NCSI_TX_EN	Input	Transmit Enable
18	GND	GND	Ground
19	Reserved
20	Reserved
21	BMC_I2C2_SDA	Input/Output	Open-drain signal
22	NIC_BMC_CTRL1, connected to BMC device pin W4 (Open Drain)	Input/Output	Open-drain signal
23	BMC_I2C2_SCL	Input/Output	Open-drain signal
24	PACK_ID2, connected to BlueField-2 device pin NIC_GPIO[46]	Input	See description above table
25	GND	GND	Ground
26	NIC_BMC_CTRL0, connected to BMC device pin Y3 (Open Drain)
27	Not Connected
28	BMC_TX5	Output	UART transmit serial data output
29	Not Connected
30	BMC_RX5	Input	UART transmit serial data input

Table D - 20-pin NC-SI Connector Pins

PACK_ID[2:0] signals allow for 8 unique card IDs. The system configurator sets the unique value per card via the connecting harness.

Pin#	Pin Name	IO	Description/Comments
1	GND	Ground	Ground
2	PACK_ID1, connected to BlueField-2 NIC_GPIO[47]	Input	See the description above table regarding PACK_ID Should be connected to the Primary controller NC-SI PACK_ID pins to set the appropriate package ID. PACK_ID0 should be connected to the endpoint device GPIO associated with Package ID[0]. PACK_ID1 should be associated with Package ID0. The baseboard should connect to GND or leave floating. DPU should have a 4.7k PU.
3	RBT_RXD0	Output	Receive data Out 0. Data signals from the network controller to the BMC. For baseboards, this pin should be connected between the baseboard NC-SI over RBT PHY and the connector. This signal requires a 100 kΩ pull-down resistor to GND on the baseboard between the BMC and the RBT isolator to prevent the signal from floating when no card is installed. For DPUs, this pin should be connected between the connector and the RBT PHY. External termination is determined by the DPU RBT PHY requirements.
4	RBT_REF_CLK	Input	RBT Reference clock. Synchronous clock reference for receive, transmit, and control interface. The clock should have a typical frequency of 50MHz ±50 ppm. For baseboards, this pin should be connected between the baseboard NC-SI over RBT PHY and the DPU cable connector. The RBT_REF_CLK should not be driven until 3.3V AUX is present on the DPU. The RBT_REF_CLK should be continuous once it has started. For DPUs, this pin should be connected between the connector and the RBT PHY. No external termination is required. 50MHz REF CLK for NC-SI BUS
5	RBT_RXD1	Output	Receive Data Out 1. Data signals from the network controller to the BMC. For baseboards, this pin should be connected between the baseboard NC-SI over RBT PHY and the connector. This signal requires a 100 kΩ pull-down resistor to GND on the baseboard between the BMC and the RBT isolator to prevent the signal from floating when no card is installed. For DPUs, this pin should be connected between the connector and the RBT PHY. External termination is determined by the DPU RBT PHY requirements.
6	GND	Ground	Ground
7	RBT_CRS_DV	Output	Carrier sense/receive data valid. This signal indicates to the baseboard that the carrier sense/receive data is valid. For baseboards, this pin should be connected between the baseboard NC-SI over RBT PHY and the connector. This signal requires a 100 kΩ pull-down resistor on the baseboard between the BMC and the RBT isolator to prevent the signal from floating when no DPU is installed. For DPUs, this pin should be connected between the connector and the RBT PHY. External termination is determined by the DPU RBT PHY requirements.
8	RBT_ISOLATE_N	Output	Signal used to indicate the SmartNIC has powered and is ready for NC-SI physical layer connection to be present. When low the baseboard circuitry will isolate the NC-SI connection to the SmartNIC. When high normal NC-SI RBT connectivity is available. Baseboards should terminate this with a 47K-100K PD resistor. SmartNICs should terminate with a 10k PU resistor.
9	GND	Ground	Ground
10	PACK_ID0, connected to BlueField-2 NIC_GPIO[49]	Input	See note above table regarding NC-SI PACK_ID should be connected to the Primary controller NC-SI PACK_ID pins to set the appropriate package ID. PACK_ID0 should be connected to the endpoint device GPIO associated with Package ID[0]. PACK_ID1 should be associated with PACK_ID[1]. The baseboard should connect to GND or leave floating. DPU should have a 4.7k PU.
11	NCSI_TX_EN	Input	Transmit enable. For baseboards, this pin should be connected between the baseboard NC-SI over RBT PHY and the connector. This signal requires a 100 kΩ pull-down resistor to ground on the baseboard between the RBT isolator and the DPU cable connector to prevent the card-side signals from floating when the RBT signals are isolated. For DPUs, this pin should be connected between the connector and the RBT PHY. External termination is determined by the DPU RBT PHY requirements.
12	GND	Ground	Ground
13	NCSI_TX_D0	Input	Transmit Data In 0. Data signals from the BMC to the network controller. For baseboards, this pin should be connected between the baseboard NC-SI over RBT PHY and the connector. This signal requires a 100 kΩ pull down resistor to GND on the baseboard between the RBT isolator and the DPUcable connector to prevent the card-side signals from floating when the RBT signals are isolated. For DPUs, this pin should be connected between the connector and the RBT PHY. External termination is determined by the DPU RBT PHY requirements.
14	BMC_RX5	Input	UART transmit serial data input. 3.3V UART TX signal from the baseboard Ground
15	NCSI_TX_D1	Input	Transmit Data In 0. Data signals from the BMC to the network controller. For baseboards, this pin should be connected between the baseboard NC-SI over RBT PHY and the connector. This signal requires a 100 kΩ pull-down resistor to GND on the baseboard between the RBT isolator and the DPUcable connector to prevent the card-side signals from floating when the RBT signals are isolated. For DPUs, this pin should be connected between the connector and the RBT PHY. External termination is determined by the DPU RBT PHY requirements.
16	BMC_TX5	Output	UART transmit serial data output. 3.3V UART TX signal to the baseboard.
17	PRESENCE_N	Output	Presence of SmartNIC The baseboard should implement a 200 Ω series resistor and 4.7kohm pull-up resistor to 3.3V AUX. SmartNIC should tie this to GND.
18	GND	Ground	Ground
19	NCSI_ARB_IN	Input	NC-SI hardware arbitration input If the baseboard supports multiple DPU cards connected to the same RBT interface, it should implement logic that connects the RBT_ARB_IN pin of the first populated DPU card to its RBT_ARB_OUT pin if it is the only card present or to the RBT_ARB_OUT pin of the next populated card and so on sequentially for all cards on the specified RBT bus to ensure the arbitration ring is complete. This logic should bypass slots that are not populated or powered off.
20	NCSI_ARB_OUT	Output	NC-SI hardware arbitration output. If the baseboard supports multiple DPU cards connected to the same RBT interface, it should implement logic that connects the RBT_ARB_OUT pin of the first populated DPU card to its RBT_ARB_IN pin if it is the only card present or to the RBT_ARB_IN pin of the next populated card and so on sequentially for all cards on the specified RBT bus to ensure the arbitration ring is complete. This logic should bypass slots that are not populated or powered off.

Last updated: February 13, 2023