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Hello. I have a a quick question. Warnning you it may sound a little dumb/noob but it's been a while.
1. If changing to 2.019 crystal my song playback tempo in lsdj will change too?. (Can't rememebr if song speed only counts for sync port). If yes, is there a way to only vari pitch and not tempo.
2. Is it possible to completely replace DMG osc crystal with a 555 timer?
Thanks for your answers.
1. Yes, the tempo will change. You can however have the tempo controlled externally, so it will remain constant.
2. Sure, as long as the output signal is clean and stays within the safe freq range. The reason so may people use the LTC is because it requires so any fewer components to get it running. A 555 timer will require resistors and caps, whereas the LTC just needs a resistor or two.
1. Yes, the tempo will change. You can however have the tempo controlled externally, so it will remain constant..
So, lets say, the "master" would be the unmodified dmg with the 4.19 xtal and the slave will be the half speed modded 2.09 xtal?. Hmm.. I thought the sync master overrides the slave clock... but the z80 slave keeps using his own xtal for sound cycles?, is there a risk of a processor crash here maybe?
2. Sure, as long as the output signal is clean and stays within the safe freq range. The reason so may people use the LTC is because it requires so any fewer components to get it running. A 555 timer will require resistors and caps, whereas the LTC just needs a resistor or two.
I'm ok with resistors and caps. 555 easier to get, LTC not available locally. I think I saw an schematic aplication on the 555 specs sheet that could work but can't rememebr. Has anyone else already tried this? because I'm not sure about the ranges or cleanliness, as I remember 555 will distort pretty bad at some freqs.
Last edited by Val (Nov 9, 2014 11:15 pm)
1. Crashes can occur, but what you're worried about is data not being processed in time, correct? In that case, if sound data cannot be processed fast enough like tablesfor example, and a new note is triggered, then the remaining parts of your table will be skipped. Crashing will probably only occur when you leave that safe range.
2. Give it a shot. Lets find out. You can always clean up the edge of your clock signal with transistors or logic IC's.