- In order to ensure that the BIOS checksum is correct at boot time, and
- hence that the onboard BIOS extension gets executed, the DiskOnChip
- goes into reset mode when it is read sequentially: all registers
- return 0xff until the chip is woken up again by writing to the
- DOCControl register.
-
- Unfortunately, this means that the probe for the DiskOnChip is unsafe,
- because one of the first things it does is write to where it thinks
- the DOCControl register should be - which may well be shared memory
- for another device. I've had machines which lock up when this is
- attempted. Hence the possibility to do a passive probe, which will fail
+ In order to ensure that the BIOS checksum is correct at boot time, and
+ hence that the onboard BIOS extension gets executed, the DiskOnChip
+ goes into reset mode when it is read sequentially: all registers
+ return 0xff until the chip is woken up again by writing to the
+ DOCControl register.
+
+ Unfortunately, this means that the probe for the DiskOnChip is unsafe,
+ because one of the first things it does is write to where it thinks
+ the DOCControl register should be - which may well be shared memory
+ for another device. I've had machines which lock up when this is
+ attempted. Hence the possibility to do a passive probe, which will fail