MOSI/MISO and 140 Years Of Wrong @make

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MOSI/MISO and 140 Years Of Wrong

The engineers who developed SPI in the late 1970s had to come up with a shorthand to indicate that one component controlled the data dialogue and gave the orders, while the other took the orders and only responded within a limited set of expected norms. Master/Slave was the engineering norm.

But these words are not appropriate and we at Make: will stop using those terms in our books, magazine, and online articles. Unfortunately, that can’t erase the millions of MOSI/MISO boards already in existence. What do we do about them?

Following what we think will become standard practice, from now on, our default for MOSI/MISO will be to call them “Main Out/Serial In” and “Main In/Serial Out”, a practice already being followed by Adafruit and others. When more information is available about a specific circuit, the initials can become more precise …

…the Open Source Hardware Association (OSHWA) has put forth a proposal to rename “master” and “slave” components to “controller” and “peripheral”. As we wait for COPI/CIPO boards to become the norm, we welcome these changes to nomenclature throughout the electronics industry.

Read more.


Featured image on MAKE by Artur Shamsutdinov from Pixabay.

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