======================================================================<< PROCEDURE FOR READJUSTING THE REZERO FLAG MANUALLY ON MINISCRIBE DRIVES<< PURPOSE:<< If a Miniscribe M7 or M11 drive does not boot and the LED code shows<< an on,flash,on,flash code type A, designating a track zero interrupt<< error, it may be possible to realign the rezero flag using this<< procedure and the onboard electronics.<< EQUIPMENT NEEDED:<< Drive power supply; check for good 5 and 12 volts<< Torque driver with 5/64" allen bit set to 4 in-lbs<< Torque driver with 5/64" allen bit set to 5 in-lbs<< Extender cables for the spin, stepper motors and the<< rezero sensor.<< CAUTION:<< Setting the dip switches or jumpers as described below, will send<< high current through the stepper motor circuitry. Try to prevent<< damage by leaving the drive in this mode for a short duration only.<< PROCEDURE:<< A. Drive preparation -<< 1. Remote the printed circuit board assembly (PCBA) from<< the drive and attach an LED to it (if it is not<< possible to leave the faceplate LED attached).<< 2. Attach extender cables to the PCBA and connect to the<< spin motor and the rezero sensor, leaving the<< stepper motor unconnected.<< 3. Connect the power to the drive's PCBA and apply the<< power to the drive.<< 4. After the full spin speed is reached, manually rotate<< the stepper motor shaft clockwise to the crash stop.<< 5. Remove the power and connect the stepper motor<< extender cable that was previously unattached.<< 6. Set the dip switches on the 3425 and 3438 as follows:<< SW2 - closed SW3 - open.<< Set the jumpers on the 3425P, 3438P, 3650 and 3675<< as follows:<< JP1 - closed JP2 - open.<< Note that SW4 and JP3 control the rezero adjust feature.<< B: Adjusting the rezero flag -<< 1. Apply power to the drive, let it reach operational speed and<< watch the motor until it moves (approximately 20 seconds after<< applying power).<< 2. Loosen the screw on the rezero flag and rotate it until it is<< within the rezero sensor. Notice that as the flag is rotated<< counterclockwise from within the sensor, the LED will turn on<< then off. Carefully position the flag at the on-off location<< and tighten the screw to 4 in-lbs without allowing the stepper<< motor's shaft to turn to another 'notch.' Check that the flag<< is centered between the sensor's sides.<< 3. Apply light rotational pressure to the rezero flag. Slight<< pressure should cause the LED to toggle on and off. If it<< does not, rezero the flag as in step B2.<< C: Verification of adjustment -<< 1. Remote power from the drive and immediately rotate the stepper<< shaft clockwise to the crash stop before the spin motor slows<< down.<< 2. Reapply the power.<< 3. Recheck the adjustment of the flag as in step B3, and readjust<< per Section B. Always verify the adjustment as above.<< 4. Remove power from the drive.<< 5. Place SW3 or JP2 (depending on the model) into the closed<< position for normal operation.<< 6. Remove the extender cables and replace the PCBA, torquing the<< screws to 5 in-lbs.<< 7. Apply power to the drive. The drive should recalibrate<< without any error codes. The A code means that the adjustment<< is not yet correct and rezeroing the flag is necessary. For a<< definition of the flash codes see the product manual.<< =======================================================================<< One of the fellows originally giving this out said not to worry aboutrect and rezeroing the flag is necessary. For a<< definition of the flash codes see the product manual.<< =======================================================================<< One of the fellows originally giving this out said not to worry about<< the torque too much. I'd guess just not over-torque the screws.<< Also, someone said that if you disconnect the connector going to the<< R/W heads, you end up with enough slack on the PC board that extender<< cables are unnecessary. Also, after manually rotating the rezero flag<< clockwise to the crash stop, but prior to pulling the J2 jumper,<< another person adjusted the screw for a sort of snug friction-fit. By<< continuing to try to turn the flag clockwise against the crash stop,<< it is possible to get a friction-fit which facilitates the remainder<< of the procedure, while avoiding moving.<< =======================================================================<< From: Bob Smitter<< To: Gjoseph Peck<< Subj: Miniscribe "blink codes"<< Miniscribe hard disk error codes<< --------------------------------<< You read the error codes in a binary 'morse code' type manner.<< Zeros are indicated by a short 1/2 second flashing LED and ones<< by a 1/2 second continuous on LED.<< There are 4 of these that make up the error code, a 1 second<< pause, and the error repeats itself again. Here are the codes:<< 0000 = 0 - Microprocessor ram error<< 0001 = 1 - Microprocessor rom checksum error<< 0010 = 2 - Interface chip diagnostics failure<< 0011 = 3 - Write fault latch will not reset<< 0100 = 4 - Index pulse not detected during spinup<< 0101 = 5 - Unable to reach 3600 rpm in 30 seconds<< 0110 = 6 - Unable to stabilize spin speed in 10 seconds<< 0111 = 7 - Unable to maintain spin speed to 0.5% of normal rpm<< 1000 = 8 - Unable to uncover track 0 sensor<< 1001 = 9 - Unable to cover track 0 sensor<< 1010 = A - Track 0 sensor misadjusted<< 1011 = B - Shipping zone error, crash stop misadjusted<< 1100 = C - Carriage stuck during recal<< 1101 = D - Seek error during burn-in or recal<< 1110 = E - not used<< 1111 = F - Unexpected interrupt from processor<< --+---------------------------------------------------<< I did the above without the extender cables on a 3425 and it's my boot<< drive now, works fine. Took two tries to get the adjusment right -<< about 45 minutes from case open to case close.<<