µKenbak-1 WiFi

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I had previously built a Bluetooth dongle to attach to my µKenbak-1 (see µKenbak-1 Bluetooth). After Chris showed us how to add WiFi to the AltairDuino, I used additional ESP-01s modules to add WiFi to my nanoKenbak-1 and my sc131. I still had a couple ESP-01s modules left, so why not add WiFi to the µKenbak-1 too? I built this new dongle in an old DSL filter case (like its Bluetooth predecessor, it is powered through pin 9 of the RS-232 DB-9 connector, wired to Vcc inside the µKenbak-1.) I used the ESP-LINK firmware set to 38400 baud, but the Chris' WiFiModem firmware would work just as well.

Note that the ATMega328 can only be programmed over a hard-wired RS-232 connection because neither dongle supports the hardware handshaking lines (see μKenbak-1 Can the ATMega328 be programmed through its serial port?).

Letting it all hang out for testing.

Stuffed into the case

Ok, now it's officially a dongle

More pics in next post (Google is complaining this one is too long)

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The rest of the pictures:

Now it's officially a dongle

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Well, it turns out that the jeelabs' ESP-LINK firmware has a fatal flaw - it disconnects the TCP/IP connection if no data is sent or received for 5 minutes (it's actually documented as doing this). So while it had been working fine for my SerialBCDClock program (which prints the time to the serial port every ~10 seconds), the window kept disappearing when running my serial port adding machine program (AddingMachineV13) because it only prints output when it receives input. So I ditched the ESP-LINK firmware completely and switched to the WiFiModem firmware (customized for the µKenbak-1). Now the terminal window stays open until explicitly closed. I see no practical use for the ESP-LINK firmware for this type of application.