The firmware update is simple to install. Use Ethernet or MIDI from any computer that has a suitable basic program.
For Ethernet connection you need a special CAT5 "Crossover" cable, or a small network hub.
Regarding software, winFTP is no longer free. I like WinSCP but it's a bit complex to set up. Filezilla will also work.
The original Alesis Freeloader is ancient but may still work in some systems.
There's an entire chapter in the HD24 manual detailing how to set up an Ethernet connection. A simplified step-by-step
update guide has been posted in the files section of the HD24 Yahoo group here. (FirmwareUpdateProc-WinFTP.txt)
It's a bit easier to update the HD24's operating system software via MIDI. Connect using any general-purpose MIDI
computer interface that supports sysex files. I use a M-Audio Uno MIDI-USB cable that costs around $25. For software
on Windows computers, use MidiOX , and for other platforms, any program that can send a MIDI sysex file.
Be sure you install the manufacturer's driver for the Uno or whatever interface you use.
Don't rely on the default Windows USB driver which won't work correctly, failing to complete the update at around 96%
Here's the procedure, from page 68 of the HD24 manual:
1. Connect the MIDI output of your computer or other source of the software to the MIDI IN of the HD24.
2. Press the MIDI button until you reach page 3:
Load Code? Y /N
3. Press the YES (^) button.
The display will read:
OLD CODE? Y /N
4. Press the YES (^) button.
The HD24ís display will read:
Waiting for Software
5. Start sending software from the source device
(computer, HD24, etc.). This process takes around 9 minutes over MIDI.
Set up your MIDI software to use send buffers of 256 bytes with a delay of around
100 msec between buffers. This will prevent data over-run errors in the HD24.
Download HD24 OS 1.21 file