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STARUP FAULT WITH HARRISON 280 CNC LATHE
Posted: Tue 04 Nov , 2008 21:37 pm
by DAVID WILES
CAN ANYONE BE OF ASSITANCE? MY CNC LATHE WITH DENFORD CONTROL HAS DEVELOPED A FAULT UPON STARTUP. WHEN THE LATHE
IS POWERED UP IT FAILS TO BOOT UP COMPLETELY AND DISPLAYS THE
FOLLOWING MESSAGE
00640K SYSTEM RAM PASSED
00384K EXTENDED RAM PASSED
PRESS ESC TO SKIP MEM TEST (WHAT ESC KEY?)
00640K SYSTEM RAM PASSED (WHICH KEEPS COUNTING UP THEN WHEN REACHES 640K RESETS TO 0 AND COUNTS UP TO 640K AGAIN AND REPEATS ITSELF). I HAVE CHECKED THE MAIN BOARD AND IT APPEARES TO BE OK WITH THE RAM CHIP SEATED CORRECTLY.THE SIX DIGIT DISPLAY SHOWS THE LETTER 'L' WITH A FLASHING DOT IN THE LOWER L/H CORNER IAM UNABLE TO DETERMINE WHAT THIS MEANS. ANY HELP WOULD BE GREATLY APPRECIATED MANY THANKS -DAVE
Posted: Tue 04 Nov , 2008 22:53 pm
by Martin
It may be worth looking at computer power supply. The DSP computer will reboot if the 5 volts drops to below 4.65 volts. The easiest way to measure it is to connect a multimeter to the power plug goining to the floppy discs drive. There are only two wires there & you need to be on DC volts. If it is low then you can adjust the pot on the computer power supply. It should be mounted somewhere near the rack & covered by a brass/gold mesh box. There is only one pot that can be adjusted so it should be simple to check.
If there is still a problem then try to reset the computer Bios. connect a computer qwerty style keyboard to the socket on the side of the electrical box. Power up the machine & then press "ctl" "alt" "s" at the same time. in the Bios check that the disc drive "a" is set to 3 1/4" 1.44MB.
STARTUP FAULT 280 CNC LATHE
Posted: Tue 11 Nov , 2008 21:33 pm
by DAVID WILES
HAVE JUST CHECKED COMPUTERS POWER SUPPLY WITH METER AND AT
NO POINT DID THE VOLTS DROP BELOW 5.06 V. I CONNECTED A KEYBOARD TO THE MACHINE TO TRY AND RESET THE BIOS AS SUGGESTED BUT THIS SEEMED TO HAVE NO EFFECT AS THE CONTROL CONTINUED WITH ITS SYSTEM RAM TEST AND KEPT RE CYCLING AT 640 K. CAN YOU CLARIFY HOW TO RESET THE BIOS AS I MAY BE GOING ABOUT IT WRONG? OR HAVE YOU ANY OTHER SUGGESTIONS? THANKS AGAIN - DAVE
Posted: Tue 11 Nov , 2008 22:00 pm
by Martin
Hi David,
It does sound like the PC may be faulty. Have you tried re-seating it? (Pull it out of the rack & then insert back in). The "esc" key is the one on the qwerty keyboard now you have if fitted.
Posted: Wed 12 Nov , 2008 10:01 am
by Denford Admin
I'd guess that the BIOS memory test is failing - can you find the ram chip(s) and re-seat them ?
Alternatively, you could see if its possible to turn the memory check off in the BIOS
If there was a problem with the floppy disk, you'd normally get a boot failure message after the BIOS checks had finished.