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Serial port connection to my board

Hi

It is the basic thing but something is wrong in my set up.

I have a laptop with docking station and I can connect to my development board. Development board boots and I see the uboot loader. Hardware of port is NS16550A. Actually it works even without docking station. Newer laptop year 2003.

I have another laptop without docking station and when I connect the board there no log in minicom. Hardware of port is 16550A. Older laptop year 2000.

I use the same cable and same software. Kernels are different but serial ports are configured when I check dmesg. I set same values to ports with setserial. One laptop is older than other but both are IBM ThinkPads.

Is there difference in serial ports (I mean in hardware level)? Some voltage values are lower than others? I have seen signal level difference in LPT ports but not in serial ports.

Any suggestions how I can get it work in older laptop?

Thanks Indrek

Reply to
nanoip
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Did you also try with handshake signals disabled?

jbe

Reply to
Juergen Beisert

I know this may sound dumb, but could one laptop's serial port be set as a DTE while the other is set as DCE ?

If you have a breakout box try swapping pins 2&3 on the serial and see it that works.

G
Reply to
gfine

Thanks Juergen and gfine

I continued my testings with kermit. There I set handshake off. Currently I do not have other box for testing.

At least I got something out. I tried to change some values but no help.

I list here my D9 cable as well

2-3 3-2 4-6 5-5 6-4 7-8 8-7

Thanks, Indrek

-------------------------------------------------------------------- C-Kermit 8.0.211, 10 Apr 2004, for Linux (/home/nanoip/) C-Kermit>show com

Communications Parameters: Line: /dev/ttyS0, speed: 115200, mode: local, modem: none Parity: none, stop-bits: (default) (8N1) Duplex: full, flow: none, handshake: none Carrier-watch: off, close-on-disconnect: off Lockfile: /var/lock/LCK..ttyS0 Terminal bytesize: 8, escape character: 28 (^\)

Carrier Detect (CD): Off Dataset Ready (DSR): Off Clear To Send (CTS): Off Ring Indicator (RI): Off Data Terminal Ready (DTR): On Request To Send (RTS): On

(/home/nanoip/) C-Kermit>c

Connecting to /dev/ttyS0, speed 115200 Escape character: Ctrl-\ (ASCII 28, FS): enabled Type the escape character followed by C to get back, or followed by ? to see other options.

---------------------------------------------------- =F3a^=C2N =A5=FB=CAw=9F=FBYw=9FkJ=F7=FD=C7FB'=FE=D2=82=C2=C2B=F3s'P&=EF=F7=FE

Reply to
nanoip

And the same newer laptop. Evriting works in kermit like in minicom.

---------------------------------------------------------------------------------------------------- cat .kermrc set line /dev/ttyS0 set handshake none set flow-control none set modem type none set speed 115200 robust set carrier-watch off

# kermit C-Kermit 8.0.211, 10 Apr 2004, for Linux Copyright (C) 1985, 2004, Trustees of Columbia University in the City of New York. Type ? or HELP for help. (/home/nanoip/) C-Kermit>show comm

Communications Parameters: Line: /dev/ttyS0, speed: 115200, mode: local, modem: none Parity: none, stop-bits: (default) (8N1) Duplex: full, flow: none, handshake: none Carrier-watch: off, close-on-disconnect: off Lockfile: /var/lock/LCK..ttyS0 Terminal bytesize: 8, escape character: 28 (^\)

Carrier Detect (CD): Off Dataset Ready (DSR): Off Clear To Send (CTS): Off Ring Indicator (RI): Off Data Terminal Ready (DTR): On Request To Send (RTS): On

(/home/nanoip/) C-Kermit>c Connecting to /dev/ttyS0, speed 115200 Escape character: Ctrl-\ (ASCII 28, FS): enabled Type the escape character followed by C to get back, or followed by ? to see other options.

U-Boot 1.1.6 (Jul 18 2007 - 16:32:32)

DRAM: 64 MB Flash: 64 MB env_relocate[208] offset = 0x0 env_relocate[226] malloced ENV at a305c008 Hit any key to stop autoboot: 0 ## Booting image at 00080000 ... Bad Magic Number

..... and uboot is there.......

What happens in my older laptop?

Indrek

Reply to
nanoip

Hi

I think that my problem is solved!

The laptop is so old that there are problems with ACPI. I have compiled kernel 2.6.22. In dmesg I noticed that ACPI is disabled automatically by kernel but it seems that it is not enough.

I disabled acpi in menu.lst as kernel parameter.

Thanks Indrek

Reply to
nanoip

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