Eventually I made a thread about them some time ago.
Digged them out again, ordered some new 16F54 controllers (arrived today).
Having many blank PCBs here, I'd be interested to assemble a few + sell them.
They are very small.
How much could I charge for one?
Also the assembly is not easy. I have yesterday improved the TSSOP soldering- I get perfect alignment now. And it goes a lot faster.
With a broad tip (paid nearly 50 dollars for replacement tips), I make a big solder ball, and then touch one side of pins row with the solder ball!
Result is the IC becomes attached, without any movement. It is really bad if the IC moves just 100 micrometers- TSSOP is just 0.625 mm between each pin. The real free space between pins is about 300 micrometres!
Any misalignment, and it becomes very hard to remove the solder, even with a pump.
With the new method, I can pull off solder with the broad tip, apply flux and clean out all the gaps, and that's it!
2
The serial port is done in software, it is possible to monitor signals on the pins, and then send data just at the right time but I decided against that.
Instead, each time the display is updated, the controller chip must be reset! Then it waits for serial data. Result is, the display goes blank for 20 milliseconds. Not visible when using LCD but with a LED display, it is slightly visible.
Interface is 3-wire: RESET, DAT and CLK.
Any ideas or comments? Yes I know, hardware serial port would be better.
Digged them out again, ordered some new 16F54 controllers (arrived today).
Having many blank PCBs here, I'd be interested to assemble a few + sell them.
They are very small.
How much could I charge for one?
Also the assembly is not easy. I have yesterday improved the TSSOP soldering- I get perfect alignment now. And it goes a lot faster.
With a broad tip (paid nearly 50 dollars for replacement tips), I make a big solder ball, and then touch one side of pins row with the solder ball!
Result is the IC becomes attached, without any movement. It is really bad if the IC moves just 100 micrometers- TSSOP is just 0.625 mm between each pin. The real free space between pins is about 300 micrometres!
Any misalignment, and it becomes very hard to remove the solder, even with a pump.
With the new method, I can pull off solder with the broad tip, apply flux and clean out all the gaps, and that's it!
2
The serial port is done in software, it is possible to monitor signals on the pins, and then send data just at the right time but I decided against that.
Instead, each time the display is updated, the controller chip must be reset! Then it waits for serial data. Result is, the display goes blank for 20 milliseconds. Not visible when using LCD but with a LED display, it is slightly visible.
Interface is 3-wire: RESET, DAT and CLK.
Any ideas or comments? Yes I know, hardware serial port would be better.
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