RS485 RS232 and all Serial for GPIO

Have been working on projects with GPIO to unusual sensors. Intermediate idea:

Let any more GPIO peripherals be SPI for now?

 

I looked around for sensors prepackaged SPI sensors in the SD form factor.

ala Horwoitz and Hill Chapter 15  with no luck...

 

See Chapter 15 of latest Horowitz and Hill - Art of Electronics.
  https://artofelectronics.net/ 

 

 Look particularly at the tables/diagrams of SPI and I2C peripherals.
 Table 15.20 p1080 All IO
 Table 15.21 p1083 SPI
 Table 15.22 P1085 I2C

 

One could use the 6x1 pin header Digilent PMOD Standard for SPI.

Digilent PMOD Getting Started

There are many PMOD sensors available COTS.

 

Put in a secondary SPI header/socket on the existing SPI bus. Use the GPIO for CS.

The CS would also control power to the sensor in the socket.

One could not talk to sensor and SPI memory at exactly the same time. But maybe no big drawback?

 

One could also do TTL RS485 or RS232 to a UART to SPI bridge ala FT9xx. (or similar) on a bigger daughter board. Again a GPIO would be needed for CS and power ON/OFF for the target sensor on the bus. In fact one would power up and down the whole FT9xx as needed to conserve power.

Toys, Open Source Hardware, Littlebits.

Seems like new important technologies can often get a beach head in toys or playthings. Batteries, Energy harvesting, AI and Watson... Regardless - toys are fun.

It is said there are five proto-toys - seen from the earliest times: ball, doll (including animals), stick/stylus, string/rope/cord, musical-instrument (like wind and percussion instruments) .

Magnifying glass, magnets, and telescopes are some nice more "advanced" toys. Blocks and vehicles come along too. My personal favorites are classic construction toys.

The modern age has brought electronics and tablets as toys. Especially electronic toys and kits. Brings to mind the venerable first handhelds.

At the OHS2013 at MIT was introduced to Littlebits. They gave away a small sample kit. Very intriguing.

And the idea has gotten legs. Search for littlebits pops up many things. There is an Internet of Things connection with the cloudbit.

So it seems littlebits is becoming the Internet of Things construction toy. They want to be an app store for hardware designs with the bitlab.

Littlebits are in many ways "perfect"... though one caveat is cost (for a toy)... but it is understandable. And it leads one to think of alternatives (and a marketplace) - which has its ecosystem benefits (for littlebits and others). Might come back to that in a later blog entry.

For now thinking of ways that the deluxe Popular Science kit might be used -(sorry)- played with *grin*.

Reference Books for Device, Apparatus and Electronics Design.

One wants to get started building a device - a mechanism, a gadget, or an apparatus. Where to start? One can learn from peers and mentors. One can read magazines like Make, Circuit Cellar and Elektor. But what are the best reference books?

Classics:
Horowitz and Hill - Art of Electronics - Long in 2nd edition. Long rumored 3rd edition.

Richardson and Smith - Experimental Techniques in Condensed Matter Physics. (okay so I have a bias *grin* knowing them)

Moore, Davis and Copeland - Building Scientific Apparatus - little bit tilted to chemistry, but excellent overall.

More modern: Pratt - Make: Electronics

More ancient: Brown - 507 Mechanical Movements (Dover)

Meet more modern peers and mentors at a Maker Festival? Or at a Hackerspace?

Or go back to the past like at the Harvard Collection of Historical Scientific Instruments?