From 4d8e12413f99f74d64fffa22bc949a368af8da1c Mon Sep 17 00:00:00 2001 From: Harald Welte Date: Wed, 23 Feb 2022 22:00:09 +0100 Subject: [PATCH] manual: Document the factory default jumper setting Also re-word/expand a bit on the situations in which NT mode or cross-over is needed. Change-Id: Ie726d4ca2e8605015a2f0384d2b435e1b40c1cad --- doc/manuals/chapters/hardware.adoc | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/doc/manuals/chapters/hardware.adoc b/doc/manuals/chapters/hardware.adoc index 0e129c2..4a1de14 100644 --- a/doc/manuals/chapters/hardware.adoc +++ b/doc/manuals/chapters/hardware.adoc @@ -44,8 +44,13 @@ up: The pin-out of the connectors can be swapped between TE and NT mode using the J4 and J5 jumper blocks on the circuit board. -A GSM BTS typically implements TE pin-out, while the icE1usb should then -use NT mode pin-out if no cross-over cable is used. +The factory default setting of the jumpers is TE-mode. + +In case you're using the icE1usb with user-side equipment such as a GSM BTS, +a PBX, a Router or the like which traditionally was attached to the public +network, those devices all implement TE mode. In such situations you need +to either switch the icE1usb to NT mode (and use straight wiring), or use +an E1 cross-over cable. .Pin-out of RJ45 E1 connectors [options="header"]