I got it working finally :)
For the benefit of others, the following posting helped:
http://ecos.sourceware.org/ml/ecos-discuss/2002-07/msg00092.html
to quote the relavent instructions:
1) In the "Serial device drivers" section, I enabled the "TTY-mode serial device drivers" subsection (CYGPKG_IO_SERIAL_TTY = 1).
2) In the "TTY-mode serial device drivers" subsection, I enabled the "TTY-mode channel #0" subsection (CYGPKG_IO_SERIAL_TTY_TTY0 = 1).
3) In the "TTY-mode channel #0" subsection, I specified "TTY-mode device channel #0 device" as "/dev/ser0" (CYGDAT_IO_SERIAL_TTY_TTY0_DEV = "/dev/ser0")
4) I also did 2 and 3 for "TTY-mode channel #1" subsection, but this may not be necessary
5) Check the "Hardware serial device drivers" sections thoroughly to make sure they are what you want for /dev/ser0 (and /dev/ser1 maybe)
6) In the "ISO C Library" section, "ISO C Library standard input/output functions" subsection, I specified "Default console device" to be "/dev/tty0" (CYGDAT_LIBC_STDIO_DEFAULT_CONSOLE = "/dev/tty0")
in addition to this I activated the value
CYGDAT_IO_SERIAL_POWERPC_QUICC_SMC_SMC1
and set the device name to
"/dev/ser0"
Step 6 above I used '/dev/termios0', instead of '/dev/tty0'. I then in my source code referred to '/dev/termios0' as suggested by Andrew.
Andre