User manual

Connect Tech Xtreme/104-Plus, PCI-104 and PCI/104 Express Family User Manual
Revision 0.12
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16.4 Power-on RS485 Tri-state for multidrop networks.
Xtreme/104- Opto models offer a power-on tri-state feature to ensure glitch-free power-up on
multi-drop networks. When enabled, the Xtreme/104- Opto will hold the RS-485 transmitter in
tri-state at power up. This feature is available on ports configured as RS-485 half duplex or RS-
485 4-wire multi-drop.
Note: Enabling this feature on ports configured in RS-232 or RS-422 (RS-485 full duplex)
modes will alter the operation of the RTS signal.
16.4.1 Xtreme/104-Plus Opto and XIG 12 Port Opto models:
Jumper J1 (Xtreme/104 Plus) and J19 (Xtreme/104 Express) control the power-on tri-
state functionality. Install a jumper on the first location of J1 or J19, and configure Port 1
in RS-485 half duplex or multi-drop slave in order to tri-state Port 1 at power-on; install a
jumper on the second position of J1 to control Port 2, etc. Ports will not come out of tri-
state until the driver has loaded and transmission begins on the associated port.
Though J1 is a five position jumper, only the first four have connections to the ports on
the card. The fifth has no function.
16.4.2 16 Port Models
Jumper G485 in J18 controls the power-on tri-state functionality. Install a jumper on this
jumper to enable the Power on Tri-State function. This is a single jumper that applies to
all ports.