Before designing cables, Opal-RT recommends using the guideline: Simulator EMC cable recommendations

HDB44 Connector Pinout

As explained in OP8940 Hardware Interface, both HDB44 connectors J1 and J2 share the same pin-out

XJ2 Connector Pinout

XJ2 Signal	OP8940	XJ2 Pin	XJ2 Signal	OP8940	XJ2 Pin
P0.0	CH0	a1	P2.0	CH16	a7
P0.1	CH1	b1	P2.1	CH17	b7
P0.2	CH2	d1	P2.2	CH18	d7
P0.3	CH3	e1	P2.3	CH19	e7
P0.4	CH4	a2	P2.4	CH20	a8
P0.5	CH5	b2	P2.5	CH21	b8
P0.6	CH6	d2	P2.6	CH22	d8
P0.7	CH7	e2	P2.7	CH23	e8
GND	GND	a3	GND	GND	a9
GND	GND	b3	GND	GND	b9
GND	GND	c3	GND	GND	c9
GND	GND	d3	GND	GND	d9
GND	GND	e3	GND	GND	e9
P1.0	CH8	a4	P3.0	CH24	a10
P1.1	CH9	b4	P3.1	CH25	b10
P1.2	CH10	d4	P3.2	CH26	d10
P1.3	CH11	e4	P3.3	CH27	e10
P1.4	CH12	a5	P3.4	CH28	a11
P1.5	CH13	b5	P3.5	CH29	b11
P1.6	CH14	d5	P3.6	CH30	d11
P1.7	CH15	e5	P3.7	CH31	e11
GND	GND	a6	GND	GND	a20
GND	GND	b6	GND	GND	b20
GND	GND	c6	GND	GND	c20
GND	GND	d6	GND	GND	d20
GND	GND	e6	GND	GND	e20
GND	GND	a17	GND	GND	a23
GND	GND	b17	GND	GND	b23
GND	GND	c17	GND	GND	c23
GND	GND	d17	GND	GND	d23
GND	GND	e17	GND	GND	e23

XJ3 connector	Molex connector (on standard RTI)	XJ3 pin	OP8910
		H	VBus_A
		G	GND
		F	VBus_B
		E	GND
		D	VUser_1
		C	GND
		B	VUser_2
		A	GND

GND	GND
VBus_A	VBus_B