Perle Systems 5500152-23 manual Option description, Configuration, 485hdx, 485fdx, option

Option description	Configuration	232	422	485hdx	485fdx
	option
EIA-485 HDX local	-e	N/A	N/A	optional	N/A
echo				echoon/
				echoff
EIA-485 TX Driver	-a	N/A	N/A	optional	optional
Control				(auto/rts)	(auto/rts)
Auto EIA-485 bit delay	-b	N/A	N/A	optional	optional
				( 0 -15)	( 0 -15)

(-f)Specifies the port the action should be taken on. /dev/ttyPS1 - specifies port 1

/dev/ttyPS1,/dev/ttyPS64 -specifies port 1 through port 64 (ranges are separated by a comma)

(-l)Lists protocol configuration for each serial port configured on the UltraPort SI. /dev/ttyPS1 232 slow term 1

/dev/ttyPS1 485fdx fast term auto 5 1

The first example shows a device named ttyPS1 configured for protocol mode EIA-232, slew rate limiting is set to slow, termination is on, and the baud rate multiplier is 1

The second example shows device named ttyPS1 configured for protocol mode EIA-485fdx, slew rate limiting is set to fast, termination is on, EIA-485 HDX TX Driver Control is set to auto with bit delay of 5 bits and the baud rate multiplier is 1

(- m ) Interface mode: The valid software switchable protocol types are EIA-232, EIA-422, EIA-485 Full Duplex and EIA-485 Half Duplex. Each port on the UltraPort SI are independent of each other and therefore you may select different protocols per serial port.

(-x) Baud Rate multiplier: The baud rate multiplier allows the user to multiply the configured baud rate by 1, 2, 4, 8,16 or 32, hence achieving greater speeds on the UltraPort SI serial interfaces. This is applicable for each protocol type selected. Baud rates for EIA-232 are up to 921.6 Kbps per serial port. Baud rates for EIA-422/EIA-485 are up to 3.686 Mbps per serial port.

(-s) Slew Rate Limiting: The default setting for slew rate limiting is disabled. This will allow higher baud rate speeds on each EIA interface port. Slew rate limiting enabled, minimizes EMI and reduces reflections caused by improperly terminated cables. Operation in slew rate limited mode reduces the amplitudes of high-frequency harmonics.

(-t) Line Termination: The line termination parameter is not changeable by the user in EIA- 232 mode. However both EIA-422 and EIA-485 modes are defaulted to disabled but can be enabled by the user if needed.

UltraPort Serial Adaptors User Guide	Chapter 2 Installing drivers and host cards
Installing under Linux	Page 92