On Oct 4, 22:05, Tony Duell wrote: table). A common fault on Rodime drives was losing the index sensor output, which it uses to check the speed as it spins up. I've never found a way of fixing that completely, since it's a Hall Effect sensor inside the spindle motor. It generates two pulses per revolution, and the micro uses a special data pattern on track -2 to decide which is the real index pulse (it only needs it for formatting, really). At power-up, the micro checks the RAM and ROM, and then starts the motor and looks for index pulses. If it sees some, it then checks the speed -- there's a PLL that compares the sensor output to the reference clock (11MHz, divided down to 120Hz). If the micro doesn't see the index pulses, it generates "Fault 10" and shuts the system down. The manual for my RO350 notes that there is one jumper near the microprocessor which can be removed to circumvent the problem caused by loss of the special index info on track -2. You could try removing it, if you have an RO350 or similar. The two LEDs are for Power and Select; the Power LED flashes for fault codes. A long flash = 1, short flash = 0. 1 no index track data pattern 2 no flag 0,0 (didn't find Trk0 after 350 steps) 3 motor speed outside 1% (one!) tolerance at end of power-up sequence 4 motor speed outside 10% (ten!) tolerance in normal operation 5 flag zero stays true 6 not used 7 static Write Fault 8 RAM self test failed 9 ROM self test failed 10 no index 11 motor not up to speed I don't know if these codes are the same on other Rodime drives. -- Pete Peter Turnbull Dept. of Computer Science University of York