I have a 'fun' question. I have a USRobotics (new in box) Courier 56K Business Modem. I also have an ESP32 serial card in my CX16. So how would I configure ROMTerm, CX16 and the ESP32 to be able to use a pots line to connect to BBSes with phone numbers? Also, could I use a straight-thru D9 cable (Male to Female) with a D9 to D25 adapter?
Thank you,
Gerry
Using a Real Modem with ESP32
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ahenry3068
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Re: Using a Real Modem with ESP32
I imagine you could just enable the straight serial connection and enter the Dialing commands right in the terminal. (i.e. ATDT555-555-1212)Gerry wrote: ↑Thu Feb 13, 2025 11:19 pm I have a 'fun' question. I have a USRobotics (new in box) Courier 56K Business Modem. I also have an ESP32 serial card in my CX16. So how would I configure ROMTerm, CX16 and the ESP32 to be able to use a pots line to connect to BBSes with phone numbers? Also, could I use a straight-thru D9 cable (Male to Female) with a D9 to D25 adapter?
Thank you,
Gerry
Re: Using a Real Modem with ESP32
I have not used ROMTerm yet, but there should be an option to use the actual serial port, rather than the ESP32.
From there, you can just use a straight-through DE9 to DB25 serial cable to connect to the modem.
From there, you can just use a straight-through DE9 to DB25 serial cable to connect to the modem.
Re: Using a Real Modem with ESP32
On the back side of the TexElec card is a label that has all the port number assignments (and these are "auto-detected" by ROMTerm- so that only the available ports can be selected).
All serial RS232 is, is just an interface to talk to another device. This card supports two devices.
One device is "hardwired" to an ESP32 device that happens to "speak" TCP/IP stack, and with just a few plain-text commands will help you setup that connection (ZiModem is the code that handles parsing that plain-text into commands, mingled in with other firmware software on the ESP32 that handles the network connection and wifi encryption). ALL the ports ending in "0" connect to this device (9F60, 9FE0, 9F70, 9FF0, etc). In ROMTERM if you pick a port that ends in 0, you'll be interfacing with the ESP32 -- and so you need to set ROMTERM to whatever baudrate your ESP32 was last saved at (defaulting to 115200).
The other device (on that same card) is a "raw" 9-pin serial connection. Yes, you can 9-to-25 pin adapter that (with standard adapters still commonly available). It can be a "dongle" size adapter or along a cable. If it doesn't work, it might be a crossover or null-modem cable, so try a different one (or adding a null-modem small adapter to the end of a null-modem cable turns it back into a "regular" serial cable {usually; there are always exceptions}). So yes, you connect to a classic external modem device. As noted on the TexElec label, this device uses ports that end in -8 (9F68, 9FE8, 9FF8, etc). You'll need to set ROMTERM baud rate to whatever your external modem was last set at. If you can't remember which rate, you'll just have to go back to the ROMTERM menu and just try them all in sequence (like 1200, 2400, 9600, etc.). As you get closer to the correct baud rate, you'll start to see "garbage" characters on the screen as things get misinterpreted a little bit, but that should indicate you're getting close (these are the modem echo'ing your characters back to your terminal software, which is a good sign). Eventually you should be able to type "AT" and see an "OK" response.
But from there, on connecting the "phone line" of the modem to anything that could still dial - if you still have a landline available, it should work! GL
All serial RS232 is, is just an interface to talk to another device. This card supports two devices.
One device is "hardwired" to an ESP32 device that happens to "speak" TCP/IP stack, and with just a few plain-text commands will help you setup that connection (ZiModem is the code that handles parsing that plain-text into commands, mingled in with other firmware software on the ESP32 that handles the network connection and wifi encryption). ALL the ports ending in "0" connect to this device (9F60, 9FE0, 9F70, 9FF0, etc). In ROMTERM if you pick a port that ends in 0, you'll be interfacing with the ESP32 -- and so you need to set ROMTERM to whatever baudrate your ESP32 was last saved at (defaulting to 115200).
The other device (on that same card) is a "raw" 9-pin serial connection. Yes, you can 9-to-25 pin adapter that (with standard adapters still commonly available). It can be a "dongle" size adapter or along a cable. If it doesn't work, it might be a crossover or null-modem cable, so try a different one (or adding a null-modem small adapter to the end of a null-modem cable turns it back into a "regular" serial cable {usually; there are always exceptions}). So yes, you connect to a classic external modem device. As noted on the TexElec label, this device uses ports that end in -8 (9F68, 9FE8, 9FF8, etc). You'll need to set ROMTERM baud rate to whatever your external modem was last set at. If you can't remember which rate, you'll just have to go back to the ROMTERM menu and just try them all in sequence (like 1200, 2400, 9600, etc.). As you get closer to the correct baud rate, you'll start to see "garbage" characters on the screen as things get misinterpreted a little bit, but that should indicate you're getting close (these are the modem echo'ing your characters back to your terminal software, which is a good sign). Eventually you should be able to type "AT" and see an "OK" response.
But from there, on connecting the "phone line" of the modem to anything that could still dial - if you still have a landline available, it should work! GL