The Newton MessagePad 2000-series devices had a little known internal slot intended for an integrated modem card that was never made by Apple. PCMCIA WiFi cards of this era do not support modern WPA2 encryption. This site outlines a project to build a WiFi board for this never-used internal serial slot that works with modern WiFi networks.
Sunday, January 15, 2017
Tuesday, December 22, 2015
Instead, I've designed a replacement cover that does not interfere. For good measure, I added an embossed WiFi logo to indicate that the internal WiFi card is present.
The STL files for the port cover can be found here: https://github.com/jake-b/Newton-Internal-WiFi/tree/master/Port%20Cover
Thursday, May 7, 2015
had a stencil made and used it to apply solder paste. Then I placed the components using a very simple "pick and place" rig:
Finally, I baked it in a toaster oven that I got for free at a garage sale, and a rocket scream reflow shield.
Everything works great. I consider this project a success. All thats left to do now is to 3D print a replacement for the plastic "plug" that covers the hole in the case.
Finally, a little application that uses the method mentioned in an earlier post to enable the board when the 'modem' port is opened:
Wednesday, April 29, 2015
ThermalEarly designs used a linear regulator to supply 3.3v from the Newton's battery voltage. It became pretty obvious that a linear regulator would get too hot, and so I changed it for a switching regulator.
I wanted to do a real world test. The WiReach specs say that it can draw around 350mA peak during transmit. I modified the Thumb sample code into a program that would output a continuous stream of ~25kB packets. I taped a thermocouple to the regulator and ran the test for an hour or so.
The results were promising. From room temperature, the regulator went from 77.4F to a high of 85.1F. This satisfies me that in my normal use the board will not overheat.
A wise man once told me:
"People might be using such a Newton on a camp site close to Death Valley in August. Before you release such a circuit into the wild, you should put the assembly into the baking oven at 60 degrees centigrade and see what happens..."Good advise, but I don't think I'll be performing that test. I just can't imagine putting a Newton in a oven for any amount of time.
This test is anecdotal at best, I guess. Was the WiReach module anywhere near its peak transmit power or current draw? I don't know. At 115200bps, I'm not sure that the Newton can saturate the WiFi module such that it would need to draw its maximum.
PhysicalI found one other minor issue with the physical design. I intentionally pushed the module as close to the edge of the Newton as possible-- into the space where a telephone jack would have been for an internal modem. The module is large and getting it in just the right place and keeping the board within a 5cm square took some trial and error. Also, I wanted the antenna area as close to the edge of the case as possible.
Well this made for one unintended consequence-- the "plug" that covers the hole likely won't fit, and it will interfere with the WiReach antenna connector and board. It isn't the end of the world really -- I intend to 3D print a new plug with a little more clearance, and maybe an embossed WiFi logo so you can tell from the outside that there's a WiFi card installed.
Wednesday, April 8, 2015
I soldered leads to a 1-gate logic inverter. This wasn't easy because the part is so small. Then connect it to 3.3v, GND, and the RTS line coming out of the WiReach. Then I cut the RTS trace on the bottom of the board. I connected the output of the inverter to the input of the line driver IC.
Some Kapton tape holds it all in place. It is a really terrible hack, but it works. Hardware flow control works as expected, now.
I'm going to design a version 1.1 of the board that includes the inverter. Also I can remove the extra GPIO/Reset stuff since the "power good/reset" circuit works.
Friday, April 3, 2015
There is an error in the hardware flow control circuit, but that's due to an error in the N2 Platform documentation. I'll take responsibility because I should have more thoroughly prototyped (which I thought I had, but oh well) I'm still planning on hacking an inverter onto the board to fix the issue.
Even so. I'm chalking this one up as a success.
A few last details:
I found a really small antenna. I think its really for bluetooth devices, but it seems to work fine. It is so small, I was able to tuck it in a small gap between the power connector and the interconnect port.
AT+iWLSI=My_WiFiI use PT-100 to configure the module. Then a Serial Internet configuration with a script. The script is simple. First, it pauses for a few seconds to give the module time to power on. Second, it sends the at+iSPPP:0 command to start the PPP server. Finally, it waits for the OK.
How Does it Work?My goals when I started this were:
- The case had to close and everything had to be fully internal.
- Find an antenna and antenna placement that would work without modifying the case or the shielding.
- Enough range to reach my router from my couch...
- Connecting my Newton to a WPA2 network.
In all, despite the flow control thing, I'm pretty happy with the end result. The project meets my requirements.
I'm trying to decide if I want to do a v1.1 board with corrected flow control signals.