Ah dang, I guess I can't use this then. I'm using
Basilisk II with a Serial port mod, and the
NewtonDev setup, to connect to Einstein. Is there a way to patch an Old World rom, mainly the "1995-04 - 064DC91D - LC, Performa 580 & Performa 588.ROM" file instead? Thanks
Newton
https://newtonresearch.org/connection/ link appears to have a package Ser115200.newtonpkg that allows a Newton to use 115.2 kbps.
Maybe that Ser115200.newtonpkg package can be patched to allow 230400 bps. I don't know how to take apart, modify, and rebuild a package. The post at
https://newtontalk.newtontalk.narkive.com/Bem61qQB/help-serial-connection-pc-to-newton-suddenly-dead has a Ser230400.pkg but I don't know if that's patching the same thing or why doesn't NCX have a 23400 package?
68K/PowerPC Mac
If the Mac doesn't have the csCodes 115 and 230, then the serial controller chip needs to be programmed manually to obtain those baud rates.
#38 #29
The baud rate needs to be overridden every time it's set by the communications software. You might need to patch the communications software or patch the serial driver.
Serial ports for modern Mac/PC
You can get USB to serial adapters that support 115.2 kbps and 230.4 kbps. I have a Keyspan USA-28 and a Keyspan USA-28X that works with my Intel Mac running macOS Monterey using Serial.app's built-in drivers. Outside of Serial.app, I have to use the Keyspan drivers (Copyright © 2000-2009 Keyspan (August 12, 2009))
Emulation
You want to connect an emulated Newton to an emulated Mac? Maybe you can describe the connection you want to make, and what hardware/software you are using for the guest and host machines.
If they're both emulated, then serial port speed can be unlimited if they're running on the same host and they ignore baud rate (i.e. they don't try to limit bandwidth so a byte is transmitted instantly instead of waiting for baud period x 10 bits).
I don't know how the serial ports on Basilisk II or Einstein are created or setup. For DingusPPC, the serial port can be a unix domain socket. The `socat` command can be used to connect the socket to the terminal, a serial device, or another unix domain socket. Only the first has been tested using Open Firmware on the guest machine. That required some text pacing in DingusPPC to allow unlimited pasting of text into the terminal window. Text pacing means not always returning a character when Open Firmware reads the serial port because Open Firmware reads the serial port more often than it can buffer the characters which is strange - why read the serial port if you're not going to keep the character? Open Firmware has a `dl` (download) command which has it's own serial port reading loop which gets around that problem.
DingusPPC only emulates PowerPC Macs. That means System 7.1.2 or later. It's serial emulation doesn't support DMA yet.
I suppose the serial port emulation of DingusPPC will need the option of directly using a serial device so that it can pass different serial port options (baud rate, etc.) directly from the guest OS to a real serial port. If this is what Basilisk II is doing, then the
68K/PowerPC Mac notes above apply.