Installation guide

OS-9 V2.4 on EUROCOM-17 4 Installing new RBF Devices

Software Manual 21

4 Installing new RBF Devices

The new OS-9 V2.4 release is no longer restricted to sector sizes of

256B/sector. It now allows sector sizes of up to 32KB. For practical use,

sector sizes of 256, 512 or 1024B/sector are the most practicable. Booting

is possible from devices with a sector size ≤ 1024. Booting from floppy is

restricted to floppies with 256B/sector.

Most harddisk descriptors have the Format Inhibit bit set. This results in

error 000:255 (E$Format) when trying to format the harddisk. Reset this

bit in runtime using the dmode utility (dmode /h0 format=on).

4.1 Installing New Harddisks with Embedded SCSI Controllers

Using the hx.embscsi descriptor, the system will adapt automatically to

the new harddisk's sector size. No further action is required.

4.1.1 Changing the

Sector Size on

SCSI Drives

If you wish to change the sector size, the harddisk has to be re-formatted

physically.

Use hx.scsi256 for a sector size of 256, and hx.scsi512 for a sector size

of 512. The driver transmits a default MODE SELECT (only header +

block descriptor) and FORMAT UNIT SCSI command in order to change

the block size on the harddisk. This should work fine with most harddisks.