I am updating my old MB64 to MIOS standard
Cool, I guess it was Steve who was doing this!
I need to do my Greg board as well.
Steve (or anyone)- What else is done besides a pullup added at RC3 and the crystal swap for the 18f speed? I’ve got all the old and new schematics at the studio with the box, but no internet there.
-George
There are two 10kohm pull up resistors (check new core diagram) and ‘bypass’ capacitors, and I think there is one more resistor? (I’ll check when I get home) You can probably skip the bypass caps though. Also the backlight dimmer circuit needs to be modified… I just put a 220R 1W resistor in series with the backlight (5V) and removed the backlight transistor and base resistor from the circuit.
I think thats it… Oh, and check the core diagram for bankstick connections
oh yeah, I didn’t worry about the 100R resistor.
I am also going to try a switch to change between 10Mhz and 20Mhz Xtals if I want to change to an old firmware (PIC16F877)
…Steve
Steve -
Thanks! I’ll take this with me to the studio. I skimmed over the old and new schematics the other night too. I had more trouble figuring out where the different MBHP circuits connected to each other than anything else, but it wasn’t hard. I’m stuck in a mix right now, so I haven’t been able to do electronics out there for a couple nights. I’m anxious to see this 2x40 display in action.
I’ve still got stuff to do to my 64 before I can start construction. Some of the unneeded IC’s will likely come out, and I need to rig up temporary switches, pots, LED’s to see what I’ll use.
Like you, I figured I’d end up with an 18f on here when I was populating the board, so I ground away a recess in the PIC socket surrounding the can. Should be an easy swap.
- Take Care
Just a reminder… Greg’s PCB isn’t recommended for new boxes… unless you have one already lying around waiting to be used, or you only want a MB64 with 64pots, 16 Led’s. and 24 pushbuttons… otherwise it gets quite tricky down the track!
here are the pull up resistor details…
from pin 6 to +5v (1kohm)
from pin 18 to +5v (10kohm)
from pin 20 to +5v (10kohm)
Steve,
Thanks again for all the info. This is going to be a cue level controller for the tracking room, so it will mostly need knobs (which the Greg board seems to have plenty of). I’ve also got the add-on board if I need it. My next one should be with MBHP boards.
                                       -George
PS- I’ve got these MIDIBox guts sitting on a table, staring at me every night when I go in, and I’m stuck cleaning up a mix full of mismatch sample rate noises >:( I feel like I’ve made about six thousand crossfades in the past two days and I may be stuck doing them again tonight.