BOSS 8 EMC boot sequence

[jonny]

EMC boot sequence

Turn off all four LEDs

Send two blanks (char20) to LCD

Turn on LED 3 only

Test LCD RAM

Turn on LED 4 only

Test rest of RAM (probably unused RAM only)

Turn on LEDs 3 & 4 only

Test A to D converter AD7581 (feedrate over ride)

Turn on LED 1 only

Test/configure timers 9513A

Turn on LED's 1 & 3 only

Test/configure inturrupt controllers 9519A

Establish stack

Clear RAM from EFD2 to FDD2

Clear tool table (probably skipped if conditions are met)

Start LED 2 blinking

[Newby2]

jonny...I owe you a heaping bunch of thanks and a few cases of beer. I have been having problems with my R2E3 Boss 8 II and with your post, I was able to locate the problem! My machine would not boot beyond the A to D convertor test. LED's 3 and 4 were on, The display would show "WAIT" and the next line was showing "3"
I removed the AD7581 IC (IC25), cleaned the contacts, reinstalled and now everything is booting up and I am able to run the machine once again!
Again, have a whole bunch of beers on me!
Thankyou!
Steve

[Newby2]

With the help of jonny's post, I found a bad IC on the mother board. I also located a supplier for this chip through American Microsemiconductor, Inc. (www.americanmicrosemi.com) in Madison, NJ. At $20 bucks apiece, it was a great relief to find that I did not have to spend $600 to $700 for a replacement board.
Steve