Unable to make and receive call through PSTN confused with fxo and fxs !help-required!

I am using a Digium TDM 410P card port 1 and port 4 . In port4 I have put a pstn line but I am unable to make and receive calls from outside. I have added a ZAP trunk in which I am using channel 4 instead of g0 which now looks like ZAP4. and I have added ZAP4 to inbound call and outbound call when I call out from my free pbx it says all circuits are busy or the person you are calling is unavailable. I am totally stuck from a week on it. Help appreciated please as I am very new to free pbx. My dahdi-channels.conf looks like this:
root@localhost asterisk]# vi dahdi-channels.conf
;;; line="1 WCTDM/0/0"
signalling=fxo_ls
callerid=“Channel 1” <4001>
mailbox=4001
group=5
context=from-internal
channel => 1
callerid=
mailbox=
group=
context=default
;;; line="4 WCTDM/0/3"
signalling=fxs_ks
callerid=asreceived
group=0
context=from-pstn
channel => 4
callerid=
group=
context=default

[root@localhost asterisk]# dahdi_cfg -vvv
DAHDI Tools Version - 2.1.0.2

DAHDI Version: 2.1.0.4
Echo Canceller(s): MG2
Configuration

Channel map:

Channel 01: FXO Loopstart (Default) (Echo Canceler: mg2) (Slaves: 01)
Channel 04: FXS Kewlstart (Default) (Echo Canceler: mg2) (Slaves: 04)

2 channels to configure.

Setting echocan for channel 1 to mg2
Setting echocan for channel 4 to mg2
[root@localhost asterisk]# vi chan_dahdi_additional.conf
; custom modifications, details at: http://freepbx.org/configuration_files ;
;--------------------------------------------------------------------------------;
;

;;;;;;[4001]
signalling=fxo_ls
pickupgroup=
mailbox=4001@device
immediate=no
echotraining=800
echocancelwhenbridged=no
echocancel=yes
context=users
callprogress=no
callgroup=
callerid=device <4001>
busydetect=no
busycount=7
accountcode=
channel=>1
chan[root@localhost asterisk]# vi chan_dahdi.conf.template

;# For Dahdi/* buttons use the following
;# (where x=number of buttons to dislpay)
;# ;AMPWILDCARDLABEL(x):MyLabel

[channels]
language=en

; include dahdi extensions defined in FreePBX
#include chan_dahdi_additional.conf

; XTDM20B Port #1,2 plugged into PSTN
;AMPLABEL:Channel %c - Button %n
context=from-pstn
signalling=fxs_ks
faxdetect=incoming
usecallerid=yes
echocancel=yes
echocancelwhenbridged=no
echotraining=800
group=0
channel=>4

what do i have to include or modify? Help appriciated
below nel=>1 is nothing just a typo mistake which i couldn’t delete while posting this problem.

nel=>1