02-06-2016, 12:02 PM
I've been driving the SCP board from my own software for some time, but have noticed occasional strangeness in behaviour. I've finally spotted a pattern to it, which usually begins with me unplugging the device for more than a few seconds before use.
After opening the device I always select drive 0, turn the motor on, then seek to cyl 0. Instead of seeking to cyl 0 it seems to position the drive head at cyl -4, and using a slower than normal step rate. If I then sequentially read the content of tracks 0 upwards, the first 4 show as blank and cyl 4 shows the output from physical cyl 0, etc. If I stop my program and re-run it everything works completely normally, with cyl 0 correctly located and a normal step rate used.
It seems like I should be initialising more of the board when I first open it. Can you advise on what I need to change from the firmware defaults? I have hardware version 1.1 and firmware version 1.2 installed.
The cyl -4 issue feels like it might be related to the flippy mode somehow, which I'm not changing. I've noticed your own software doesn't suffer from the same problem, but it's likely to be applying more to restore the user's configuration settings...
After opening the device I always select drive 0, turn the motor on, then seek to cyl 0. Instead of seeking to cyl 0 it seems to position the drive head at cyl -4, and using a slower than normal step rate. If I then sequentially read the content of tracks 0 upwards, the first 4 show as blank and cyl 4 shows the output from physical cyl 0, etc. If I stop my program and re-run it everything works completely normally, with cyl 0 correctly located and a normal step rate used.
It seems like I should be initialising more of the board when I first open it. Can you advise on what I need to change from the firmware defaults? I have hardware version 1.1 and firmware version 1.2 installed.
The cyl -4 issue feels like it might be related to the flippy mode somehow, which I'm not changing. I've noticed your own software doesn't suffer from the same problem, but it's likely to be applying more to restore the user's configuration settings...