Minor correction. Any commands that get translated to an index higher
than 0x13 will return an invalid command, not crash the firmware.
This statement is incorrect: "I haven't looked for any other logic that
would prevent this, but a command 0x13 to 0x2A (except 0x23), or 0x35 to
0x3F will sel
This doesn't matter but on the TPDD1, if you set the dip switches to
OFF ON ON ON, then you can dump the rom at 19200, and in that case I
need to add a sleep after each S-record. I added 30ms just based a note
for something else somewhere in the service manual that you should wait
25ms to betwe
Nice find! I wasn't looking at port 4 data since I assumed it was all
address outputs, but P43, P44, P45 are configured as inputs on the TPDD2
(not on the TPPD1).
;Port4.B0 I/O Pin37 P40 A8
;Port4.B1 I/O Pin36 P41 A9
;Port4.B2 I/O Pin35 P42 A10
;P
I don't see anything in the code that reads the drive parameter table
other than the command to output that data. I'm guessing Brother may
have other drives with more capabilities and this is only there to tell
the host how the drive is configured.
Also I don't see anything for a second serial
The part of the code that picks out the commands is a bit goofy, but I
believe it's like this to maintain a standard command set across
multiple drives with other added functionality.
There is a bit mask for the command, so we're only looking at the lower
6 bits (0x00 to 0x3F). Bit 6 and 7 (6
This is great for making the emulators and clients definitive instead of
full of mysteries and "here we recite the words lest the gods be angry".
Can you see why command 0x11 works as a synonym for 0x33?
And why does 0x0F respond with the 0x38 return block?
When neither of those are commands. Th
I'll add some info from your nicely documented code.
* A13 value is tested at 0xF1FE, and controls a branch to 0xF1EB; seems to
change the way serial data is transmitted. hardware default is to branch.
* A12 value is tested at 0xF071, not sure what it does yet. hardware
default is to branch.
* A1
Darren, another question,
There are some inputs on pins 30,31,32 (called A13, A12, A11) that
correspond to P45, P44, P43 on the HD6301.
Port 4 of the HD6301 is hooked up to pins 73.36,35,32,32,30,29,28 for
P40-P47.
I'll go look at the code, but these 3 inputs are configurable. I wonder
what the
Thanks Darren.
Now that we have the real tpdd firmware I wonder what we can do with it.
Some of those variables look tempting, like side and # of tracks.
Another question.. it looks like was there a second unpopulated serial port
on the drive? Anything in the code on that?
P7 is unpopulated and
