TP-LINK TD-W8970 half duplex ethernet

Installing and Using OpenWrt
1

Hi, on the TP-LINK TD-W8970 the 4 external ethernet ports are connected together under br-lan.

Now my printer alas is only a 10Mbps Half Duplex device, and it seems like Open-Wrt is bring the connection up Full Duplex, at least that would be my guess, some packets get through, but generally it is huge packet loss:

ping 192.168.2.243
PING 192.168.2.243 (192.168.2.243) 56(84) bytes of data.
64 bytes from 192.168.2.243: icmp_seq=7 ttl=254 time=2.26 ms
64 bytes from 192.168.2.243: icmp_seq=21 ttl=254 time=1.64 ms
64 bytes from 192.168.2.243: icmp_seq=28 ttl=254 time=2.46 ms
64 bytes from 192.168.2.243: icmp_seq=33 ttl=254 time=1.67 ms
64 bytes from 192.168.2.243: icmp_seq=38 ttl=254 time=3.58 ms
64 bytes from 192.168.2.243: icmp_seq=45 ttl=254 time=1.48 ms
64 bytes from 192.168.2.243: icmp_seq=51 ttl=254 time=1.65 ms
64 bytes from 192.168.2.243: icmp_seq=56 ttl=254 time=1.71 ms
64 bytes from 192.168.2.243: icmp_seq=61 ttl=254 time=1.84 ms
^C
--- 192.168.2.243 ping statistics ---
61 packets transmitted, 9 received, 85.2459% packet loss, time 865ms
rtt min/avg/max/mdev = 1.477/2.032/3.577/0.625 ms

So is there a way, on these ethernet ports, hidden below another virtual one, of making just a single one half duplex?

2

worth a try... if you are comfortable with the command line...
https://openwrt.org/docs/techref/swconfig
http://forum.lemaker.org/forum.php?mod=viewthread&tid=11621
another workaround would be to place a switch between the two...

3

OK I can get this far:

root@DavidSummers:~# swconfig dev eth0 port 0 get link
port:0 link:up speed:100baseT full-duplex auto

So have found the problem port - set to full-duplex, this needs to be set to half duplex. But every method I've tried with "set link" fails - it says operation not supported.

Any ideas?

4 
swconfig list
6 
root@DavidSummers:~# swconfig list
Found: switch0 - eth0
root@DavidSummers:~# swconfig dev eth0 show
Global attributes:
	enable_vlan: 1
Port 0:
	uvr: 0
	vsr: 0
	vinr: 0
	tvm: 0
	pvid: 1
	link: port:0 link:up speed:100baseT full-duplex auto
Port 1:
	uvr: 0
	vsr: 0
	vinr: 0
	tvm: 0
	pvid: 1
	link: port:1 link:down
Port 2:
	uvr: 0
	vsr: 0
	vinr: 0
	tvm: 0
	pvid: 1
	link: port:2 link:up speed:1000baseT full-duplex auto
Port 3:
	uvr: 0
	vsr: 0
	vinr: 0
	tvm: 0
	pvid: 1
	link: port:3 link:down
Port 4:
	uvr: 0
	vsr: 0
	vinr: 0
	tvm: 0
	pvid: 1
	link: port:4 link:down
Port 5:
	uvr: 0
	vsr: 0
	vinr: 0
	tvm: 0
	pvid: 1
	link: port:5 link:up speed:1000baseT full-duplex auto
Port 6:
	uvr: 0
	vsr: 0
	vinr: 0
	tvm: 0
	pvid: 1
	link: port:6 link:up speed:1000baseT full-duplex auto
VLAN 1:
	vid: 1
	enable: 1
	ports: 0 2 4 5 6t

So I've already drilled down to the problem port, and shown the line set wrong "link:"