User manual

9
If you are using Track Play Mode, do not change banks while the machine is turned on.
If you accidentally do so, turn the machine off and on again so that the CPU reads in
crucial data from the current bank.
Unless you want to create unpredictable scrambles in the track memory, be sure to turn the
machine on and not change its memory bank at all, before using Track Write mode!
4 - Data retention and other details
(This section does not mention Dynamic Bank/Channel Switching, which is an elaboration
upon the basic 32 Bank Memory system described here.)
This modification involves removing the existing memory chips and installing a much larger
capacity memory system. Therefore it is not possible to retain the machine's memory data.
Apart from a few test patterns I write into it, the newly modified machine will contain
random data (the result of how each memory cell’s flip-flop powers up in the 0 or 1 state), so
be sure to clear each track before you start writing.
I have observed the TB-303's sequencer do some strange things, apparently with errant data
in the memory. I don't recall exactly what these things are, how to create the situation or
how to resolve it. Such strange states of data in certain patterns cannot be ruled out in any
TB-303, whether or not it has extra memory banks.
In early 2015 I changed the arrangements for battery backup of memory systems. Before
this, starting in 1996 with the V2.x Devil Fishes, I always used a large capacity cylindrical
1/2AA lithium battery soldered to the main Devil Fish circuit board. In all cases where I did
extra memory for the TR-606 or TR-808, I used the same kind of battery, again soldered in.
In early 2015, due to air-freight restrictions on lithium batteries, it became apparent that we
could only ship machines overseas, with insurance, if there was no lithium battery installed.
So machines going overseas have an internal lithium battery holder, and no lithium battery,
while machines being shipped to customers in Australia go by road and have a lithium
battery installed. These batteries should last 10 years at least, and are user-replaceable, once
the machine is partly disassembled.
Please see the separate manuals for the Devil Fish TB-303, TR-606 and TR-808 respectively
regarding the battery arrangements for memory backup.