Question on Serial Modem Configuration

[rbdr]

I have a Macintosh SE/30 and recently got a The Old Net RS232 modem. While it works wonderfully, I noticed that baud settings don't seem to change the speed that much (eg. I get about the same max speed from ftp download from a local raspberry pi from 9600 baud and 57600 baud.

I checked out my config in TattleTech and the Modem Port is listed as having "Max Baud = 57,600" but "Current Baud = 9,600". I've changed my baud settings on ZTerm and the modem and they can communicate well, so I'm wondering how much I should trust what TattleTech is telling me.

- Is the Current Baud reported by TattleTech something I should trust, or would I go with whatever I set in my terminal / PPP apps + the modem itself?
- If it is important. Is there a way to change that value?
- Is the modem port the right port? The printer port is the same connection but that doesn't seem to detect it, and I have an adapter to connect to the DB25 SCSI port but haven't tried that as the physical setup in my desk makes it a bit odd and other than the baud issue the serial port was doing OK

Any help much appreciated!

 

[cheesestraws]

I have an adapter to connect to the DB25 SCSI port

Are you sure this is a scsi adapter and not a 9 to 25 pin RS232 adapter? I don't know of any SCSI to serial adapters out there, though I'm sure someone will tell me I'm wrong here.

It's probably the latter, and if so and you plug it into the SCSI port you may well blow something up, given RS232 voltage levels are relatively high.

Proceed only with caution.

 

[Phipli]

That adapter to SCSI is not going to be a SCSI adapter - SCSI and some serial ports use the same physical connections. Don't plug serial stuff into your SCSI port, it won't work plus you might break something.

 

[rbdr]

Are you sure this is a scsi adapter and not a 9 to 25 pin RS232 adapter? I don't know of any SCSI to serial adapters out there, though I'm sure someone will tell me I'm wrong here.

It's probably the latter, and if so and you plug it into the SCSI port you may well blow something up, given RS232 voltage levels are relatively high.

Proceed only with caution.

Thanks for the warning! Good thing I haven't plugged it in. I'm using the mac modem port in the back for now. So then I either have that or the printer port as options.

 

[cheesestraws]

So then I either have that or the printer port as options.

The printer port and modem port are basically identical. I don't have any ideas about your baud rate issues - I don't use modem-like things on my Macs - but if the printer port is misbehaving that may be because it's set up for networking rather than RS232 use. Check that AppleTalk is turned off (in the Chooser)

 

[rbdr]

The printer port and modem port are basically identical. I don't have any ideas about your baud rate issues - I don't use modem-like things on my Macs - but if the printer port is misbehaving that may be because it's set up for networking rather than RS232 use. Check that AppleTalk is turned off (in the Chooser)

Thank you, that did indeed make it work on the Printer port. I seem to be getting better speeds on the modem port but not sure if it's placebo, disabling AppleTalk, or something off with my ports. TattleTech does report both as having current baud as 9600 so who knows.
One thing that I found interesting is that I can communicate with the router setting the baud to 115200 even though technically it shouldn't be supported, so I'm guessing the serial modem is doing its own thing regardless of what I set on both sides.