NitrOS9 in ROM
(development system.)
The 40K area of NVRAM
immediately after the System Settings NV RAM is reserved for a OS9 "in
ROM" boot image.The image can be booted from the virtual coco that has
been assigned U9: and defaults to using the Disk specified in Settings ROM
as /dd. You should backup your system copy before playing with this one
way is U prompt BACKUP NVR command another is to boot a NitrOS9
with a /ud9 and a /x1 device descriptor dmode and format the drivewire
image in x1 so that it is single sided with eight cylinders and twenty
(ie. $14) sectors per track on all tracks. Then the NitrOS9 command backup
/ud9 /x1 will create the backup be sure to check that drivewire has saved
it on your server before changing the original.
Although this /ud9
contains an OS9Boot file an image of this file is not boot-able from
another coco or standard emulator because no kernel track is available if
you cobbler a /ud9 drive image you get the following error.
Warning - file(s) present
on track 34 - this track
not rewritten.
However as long as the
NitrOS9 you are running has the correct kernel the drive image will boot
when copied to a CoCo5's U9: drive with the os9 backup command.
After Booting a compatible OS9 from drivewire This would be done as
follows note user input shown in bold text below.
{Term|02}/DD: dmode
/ud9 cyl=8 sid=1 sct=14 t0s=14
{Term|02}/DD: format
/ud9
COLOR COMPUTER FORMATTER
Formatting drive /x1
WARNING: You are formatting a HARD Disk..
y (yes) or n (no)
Ready? y
WARNING: You are formatting a HARD Disk..
Are you sure? y
Both PHYSICAL and LOGICAL format? y
Disk name: OS9ROM
Physical Verify desired? y
000 001 002 003 004 005 006 007
Number of good sectors: $0000A0
{Term|02}/DD: cobbler
/ud9
Now that you have the new
image saved you can use the command OS9 in BASIC from the virtual
CPU to which U9: is attached to boot the "In ROM" OS9.