Written and Maintained by Gregory Nacu

Internal SwiftLink–Compatible WiFi Modem

Last modified: Aug 10, 2020,  Page views: 1005

Home Page: http://www.pyrofersprojects.com/blog/product/internal-swiftlink-compatible-wifi-modem/
Categories: network
Compatible: c128
Price: £60.00
How to Order: Order online direct from Pyrofer's Projects Store
Documentation: https://github.com/bozimmerman/Zimodem
Top side of the internal WiFi modem

Top side

Bottom side of the internal WiFi modem

Bottom side

Top side with the integrated WiFi module added

Top side with the integrated WiFi module added

Integrated onto a c128 main board

Integrated onto a c128 main board

Similar Hardware

WiFi ModemWiModem

My Take

What a great concept, made into reality. A tiny little board, that plugs directly into the CIA socket on a c128. Thus intercepting all the important signals that would normally go to the User Port.

This board hosts the standard WiFi module with the wifi modem firmware that is used in the other WiFi modem projects, so it's compatible with existing terminal software. This little puppy takes up no additional space on the disk, requires no external power, requires no wires running into your computer at all. And yet it gets you onto modern standard networks and lets you use your preferred terminal emulator software (with a SwiftLink driver) to get on BBSes.

In my opinion, this is a quintessential device that characterizes the renaissance of retro computing.

Some random thoughts

Someone on Twitter commented that the price, at £60.00 ($78 USD) seems a bit high. But, I disagree. Retro hardware is produced in very small quantities, we should be so lucky to even have the hardware options we have.

Next, high prices for what amounts to hobbyist hardware is not new. I distinctly recall a friend back in the 90s being astonished at how expensive a CMD FD drive was. "Just for a floppy drive?!" he asked. No, the embedded PC floppy mechanism was as cheap as any other, what we paid for was the joy and delight of having that hardware hooked up to our favorite computer.

This does bring me to my last thought. The description on Pyrofer's Project's site only mentions its use on a c128. I'm not sure why it wouldn't be compatible with a C64. That's something I'll look into, and if I find out more I'll update these notes.

Want to support my hard work? Here's how!


Designed to plug into the 6526 CIA socket at the rear of the 128 (the Userport) this device is compatible with Swiftlink. This means that most comms software such as Desterm on the 128 will recognise and work with this as if it was a swiftlink cart.

Instead of an RS232 port there is a WiFi modem (ESP8266) for connection to your home WiFi network and direct BBS action. No middle proxy server is required for most BBS.

Only one jumper wire is needed, going from this board to one of the IO pins on the cart slot (pin 7 or pin 10) depending on which address you want the device to be visible at.

Because it uses a 6551 the hardware serial baud rates go much higher than the software serial userport WiFi modems.

NOT recommended for metal cased 128D system.

Installation is as simple as lifting the CIA out of it’s socket and inserting it into this board, the whole unit then plugs into the now empty socket on the C128 motherboard. A jumper wire is connected from the single header pin to the cart port IO line.

This requires some technical knowledge to install. If you are not comfortable with replacing socketed chips in the 128 or connecting the jumper wire to the cart port, please do not buy it. All units will be tested prior to sale and I will not be able to refund or replace units damaged by incorrect installation.

– Static Sensitive – Please take care when installing.

Please take note of chip orientations when installing. There is a notch at the top of each chip and this is indicated on PCB in the socket and on the board outline. Failure to correctly insert the chips will result in damage not covered by any return policy.


  • Fully assembled PCB with all components
  • 6551 chip
  • ESP8266-01 module (pre programmed with WiFi firmware)

Please note, the 6526 CIA chip is NOT included. You will need to use the existing chip from your 128.

All credit for the firmware used goes to Bo Zimmerman, full details of his WiFi modem firmware can be found here, https://github.com/bozimmerman/Zimodem