I don't know if you're still following this, but I revisited this issue today and finally got it working. You don't need to change the firmware at all. I too was struggling to make my EtherWave Printer Adapter work with the TCP/IP stuff. I'm going to turn this into a little story as I describe my journey.
First of all, I installed the Farallon driver version 2.2.2. I mounted this disk image. I opened the "For Macintosh Cards/Adapters" folder and ran the Installer. I don't remember everything I installed, but I'm pretty sure in Customize I installed EtherTalk for Farallon Macintosh Adapters and EN Driver for Farallon Macintosh Adapters. I may have done an Easy Install during testing too; I just can't remember. Sorry.
Next, in the For Adapters Only folder, I copied Adapter Setup 2.2.1 to my computer. Just for testing purposes. It's not really necessary for anything, but I didn't know that at the time.
After rebooting and all that jazz, I made sure the Network control panel was set to LocalTalk built-in and ran Adapter Setup 2.2.1. It found the adapter but told me it's not serialized, contact Farallon, blah blah blah. I cheated and disabled the serialization check by replacing it with NOPs. It checks to make sure two bytes are both not zero. It told me that my firmware is out of date. I canceled out of the update procedure though...didn't want to screw up my adapter. It turns out the firmware is available as a binary blob in a 'HEX ' resource in Adapter Setup. So you might be able to flash it manually if you ever feel like it. I'm too afraid to try the update, but it looks like I don't need it anyway.
It became blatantly obvious what is meant by "not serialized" -- the MAC address ends in 00:00. Those are the two bytes it's checking. I don't know how to set a new MAC address for it though, unfortunately. There's probably a command you can send it, but it's undocumented and I don't see anything in the Adapter Setup program's resources that looks like a screen for setting it. Oh well, not a huge deal as long as there's only one on a network. Anyway, the Adapter Setup interface is pretty boring. It lets you select an AppleTalk zone and turn on some kind of printer mode. I made sure the printer mode was OFF (it was already off by default, which I guess is surprising considering that it's the printer adapter version).
At this point I started fiddling with different settings in the Network control panel and MacTCP control panel as well as reading the included ReadMe file. I finally got it working and now TCP traffic is getting delivered correctly! Here's the magic combination.
The Network control panel has to be set for "PB Adapter". (It has to be set to LocalTalk in order to use Adapter Setup, but it has to be set to PB Adapter for the TCP/IP forwarding to work). Any other additional choices are for other weird situations. If you don't see PB Adapter, then something isn't installed correctly.
The MacTCP control panel has to be set for "Ethernet". This is somewhat surprising, but the ReadMe file says that the "PB Adapter" choice in MacTCP is if you want to use a different MacIP server and not the one built into the EtherWave. Either use the patched MacTCP 2.1 that doesn't suck, or if you're feeling particularly masochistic, stick with MacTCP 2.0.6 and calculate the network and node addresses yourself. In my experience, MacTCP's DHCP support (if you select Server under Obtain Address) didn't work with my router, so I had to manually assign an IP address.
OK. After this, I may have had to reboot, but I can't remember. If it doesn't work, then reboot and try again. Anyway, after setting everything up like that, the Printer Adapter works perfectly fine as a Mac/PB Adapter! I can ping stuff on my network with no trouble and I was able to test telnetting into my router. Definitely awesome.
Edit: I figured out how to set the serial number/MAC address. If you change the RAM that contains the MAC address and then do something in the program that causes a save, it saves the new MAC address to the EtherWave. I just added some instructions in the code I NOP'ed out earlier to set those bytes to something nonzero. Now I can run the original unpatched version of Adapter Setup with no troubles.
Yea i know. Once thats created, I could technically make a custom board that would plug into a powerbook in the modem slots, this would give us a localtalk to ethernet bridge. Hell, if you are going ARM, you could even do wifi. Localtalk to wifi bridge. Use a control panel to link the thing up.
Today I tried to test the maximum data rate through one of these things.
Previously, I tried using a PB 1400cs. It was interesting, because on the download, I measured 80.1KiB/sec, but the upload...well, it didn't work. (TCP functioned normally.) This was under 7.5.3: 7.5 is kind of on shaky ground with one of these babies. I used AFP.
So I borrowed a 7100/66 thinking the GeoPorts would give me enough room to flex this thing's muscle. GeoPorts are reputed to be able to handle a 2Mbps data rate, compared to a maximum of 921600bps of a "regular" serial port. Thing is, there is a difference between a "fast serial port" and a regular serial port: Fast serial ports apparently came with PPC and 040 boxes, not sure if GeoPorts are related. The IIfx probably came with a "fast serial port" too.
Did it work? No. Let's just say I stopped after 40 minutes because it hadn't gotten to 12.5% completed yet. Here's what I do know, in addition:
1.4 How fast can the Macintosh serial ports really go?
The Macintosh operating system supports data rates up to 57600 bps, but the Macintosh serial hardware can support transfer rates that
are much higher if they are externally clocked. Serial port sound-input-devices such as the Cedar Technologies SID and Farallon's MacRecorder, as well as AppleTalk boxes, use this trick to achieve transfer rates greater than 100 Kbps.
Ward McFarland <email@example.com> writes:
"The clock rate supplied by pre-AV Macs to the SCC (and used for bps rate generation) limits the maximum asynchronous serial speed to 57,600 bps. The maximum synchronous speed is 16 times this (as used by the old serial hard drives used on 512K Macs and by the Personal LaserWriters).
Indeed, the SCC can be externally clocked to faster asynchronous speeds, with a couple of limitiations. First, the external clock is applied to the Mac's CTS input, making it impossible to respond normally to normal modem handshake requests. Second, since the SCC used in older Macs can only buffer 3 characters, data losses can occur due to interrupt service delays. MacRecorder and other custom devices got around this by locking out all system interrupts during serial data transfer.
The AVs and PowerMacs apparently use a different SCC clock, and I have benchmarked fairly good ZModem performance using Smartcom II 4.0 at 115,200 and 230,400 bps. Apple does not publish the serial driver control call to set this, and they state they do not support such speeds. I do not know of anyone besides Hayes who has managed to get Apple to tell them the methodology.
Creative Solutions, Inc. (see the end of Part 4 of this FAQ for vendor contact information) makes a NuBus card (the "Hustler") and soon will make an external SCSI-based device that can support 2 channels at 115,200 bps or one at 230,400 bps. This is currently used by quite a number of people supporting high speed (28.8) modems and direct serial connections. This product works fine with existing communications and bulletin board system software."
Note: Powerbooks are known to have problems at extremely high data rates. These problems are caused by Power Manager overhead. System 7.1 is supposed to solve or alleviate these problems.
Note: AppleTalk being active can degrade serial port performance, as can Ethernet-network traffic. Turning off AppleTalk via the Chooser, or disconnecting the Ethernet transceiver, are work-arounds.
Dan Schwarz <Dan_Schwarz/Iris.IRIS@iris.com> adds
AVs and PowerMacs use a newer SCC chip and a DMA based serial driver that can handle a much higher async throughput than the older, interrupt-based driver.
My SerialSpeed 230 control panel takes advantage of this new driver and allows many older applications to operate at speeds of 115,000bps or 230,000bps on the PowerMac and AV Mac. It's shareware and is widely available.