Daktronics AF-3150-20-R,A - Manual (Page 30)

The controlling laptop computer connects to the J-box through a DB9 to DB25 serial
cable (refer to Drawing A-174341).
Figure 23: RS232 Display Layout
Figure 24: J-box to RS232 IN on Controller Board
J-Box to Controller
J-box Wire Color Controller (TB1)
Pin 1 (TX-P) Black Pin 5 (RX1)
Pin 2 (RX-P) Clear or Red Pin 3 (TX1)
Pin 3 (GND) Shield Pin 4 (GND)
Electrical Installation 3-10