Hi,

I'm seeking for some help with connecting to a device via serial console.
I have a CP1202 USB to TTL adapter, which I have successfully used to debrick a device before.
I'm trying to connect to a Huawei D100, I soldered the connectors to the points described in the wiki (can't post links for some reason...).

I found that 115200 is probably the best rate, but using this, I get results like this (on Windows 8.1 + PuTTY)

▒ecompressing....n.....done


CFE version 1.0.37 for BCM947XX (32bit,SP,LE)
Build Date: ▒▒ 12▒▒ 24 13:46:17 CsT 2009 (bcm@localhost.localdomain)
Copyright▒˩H▒Hx▒{▒凱▒▒幝▒
                         ɵ▒▒5
                             Initializing Devices.
Boot partition size = 262144(0x40000)
et0: Broadcom BC▒47xx 10/100 Mbps Ethernet Controller
CFE reboot no init fla▒j
                        CFE reboot glag0 = 0x12345678, flag1 = 0x0,flag2 = 0xffffffff,reboot_number = 0x1
CPU type 0x29029: 240▒Hz
▒otal memory: 32768 K▒ytes
Total memory used by CFE:  0x80400000▒  `   0x80436F60 - 0x8063B010 (16560)
BSS Area:                  0x8043B010 - 0x8043D310 (8960)
Local Heap:                0x8043D310 -`0x804A1310 (409600)
Stack Area:        ▒B▒▒▒▒▒▒▒▒▒▒▒▒       0x80400000 - 0x80436F60 (225120)
Boot area (physical):      0x004A4000 - 0x004E4000
Relocation Factor>         I:00000000 - D:00000000

▒evice eth0:  hwaddr 64-16-F0-7F-61-8F, ipaddr 192.168.1.1, mask 255.255.255.0
        gateway not`set, namesgvver not set

I tried it on another computer (Windows 10) it is slightly better, but still not working properly. On the Windows 8.1 computer I think the device detects constant keypresses, because it keeps spitting the help. Not on the Windows 10, but I can't use it there either, because keypresses don't work properly.

What could be causing this? Bad settings? Soldering error? Driver error?

Thanks!

This looks suspiciously like a floating ground issue. Looking at the wiki entry for the Huawei D100, it only shows RX and TX solder points. If you only connected those, you also need to connect GND to a ground point on the PCB (never connect VCC, though).

(Last edited by metai on 21 Jan 2018, 06:21)

Thank you! You were right. I used the point to where the black wire of the USB socket connects and now it seems to be working fine. Awesome!