SERIAL CONSOLE.

[Ezequiel Larrarte]

Hi guys, i 'm new to the list ... so sorry if this item has been posted 
(and sorry about my little English too).

I 'm trying to build a very simple system using: static 
kernel+initramfs+busybox+uclibc+serial console:

1 - compile a static kernel -> /boot/vmlinuz

2 - generate an initramfs.cpio.gz file with busybox+uclibc -> 
/boot/initramfs.cpio.gz
/etc/inittab:
::sysinit:/etc/init.d/sysup.sh
::shutdown:/etc/init.d/sysdown.sh
tty1:;respawn:/sbin/getty 38400 tty1
tty2:;respawn:/sbin/getty 38400 tty2
ttyS0::respawn:/sbin/getty -L 38400 ttyS0 vt100

/etc/init.d/sysup.sh:
#!/bin/sh
echo "-------------------------------------------"
echo "INIT"
echo "-------------------------------------------"

3 - put all these things together inside a pendrive with grub:
/boot/grub/menu.lst:
timeout 10

serial --unit=0 --speed=38400 --parity=no --words=8 --stop=1
terminal --timeout=5 serial console

title test (vga)
kernel /boot/vmlinuz rdinit=/sbin/init console=tty0
initrd /boot/initramfs.cpio.gz

title test (serial)
kernel /boot/vmlinuz rdinit=/sbin/init console=ttyS0,38400n8
initrd /boot/initramfs.cpio.gz

4 - Try booting with "test (vga)" ... everything is working fine, here 
is the output:
-------------------------------------------
INIT
-------------------------------------------

Welcome!
linux login: _

5 - When I try "test (serial)" ... this is my output:
Welcome!
linux login: _

There is no /sbin/init output on the serial console ...

6 - Try without any /etc/inittab and "test (serial)":
-------------------------------------------
INIT
-------------------------------------------

/$ _

It works! ... something wrong with the /etc/inittab file?

7 - put a "sleep 2" at the bottom of /etc/init.d/sysup.sh, with my 
/etc/inittab and "test (serial)":
-------------------------------------------
INIT
-------------------------------------------

Welcome!
linux login: _

It works!
I 'm trying this with my Pentium IV 3.0 Ghz ... I tried with another PC, 
it 's the same.

And sometimes I get this output:
---------------

Welcome!
linux login: _



Timing problem? serial port flush bug? busybox-init bug?
My serial port is shown as UART type 16550A, kernel 2.6.24|2.6.20|2.6.18

Thanks for the help ....
Ezequiel Larrarte.