ABC of electronics terms
Networks
(Synchronous) Serial Peripheral Interface
This is one of the three major serial in-system communication methods
(together with I2C* and Microwire). Someone asked me to add the entries for
Microwire and SPI, but I haven't really got good links yet. I used to
program a lot for SPI devices connected to 6811's and other MCU's.
The 6811 has a nice inbuild SPI interface, so try to get the 'pink book'
about the 6811 from Motorola. Also get some databooks from Catalyst and
others with small serial EEPROM's. It's also easy to connect standard
74HCT* series serial shiftregister to expand the number of ports of a
microcontroller. The SPI definitions aren't as solid as those of I2C*
but the parts are usually much cheaper and the programming is much
easier. The I2C* bus only needs two lines: Clock and data, but the SPI bus
has seperate in and output lines and also a clock line. It also needs a
latch line, to signal to the devices that the data isn't shifting anymore
and can be used (or needs to be read in again). SPI is a great way to
add extra (but slower) I/O pins to a MCU. It's fast enough however to
connect slow devices like keyboards and LCD-screens to.
See also:
Companies
My company, Total Phase, has just launched a new I2C* host adapter.
On our website is documentation about I2C* and SPI, as well as some example code.
Would it be possible to get a listing?
Derek Fung
See also:
- Site version is

- Page last edited on 20040726
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