Documentation
¶
Overview ¶
Package spi allows users to read from and write to an SPI device.
Deprecated ¶
This package is not maintained anymore. An actively supported cross-platform alternative is https://periph.io/.
Example ¶
Example illustrates a program that drives an APA-102 LED strip.
package main
import (
"golang.org/x/exp/io/spi"
)
func main() {
dev, err := spi.Open(&spi.Devfs{
Dev: "/dev/spidev0.1",
Mode: spi.Mode3,
MaxSpeed: 500000,
})
if err != nil {
panic(err)
}
defer dev.Close()
if err := dev.Tx([]byte{
0, 0, 0, 0,
0xff, 200, 0, 200,
0xff, 200, 0, 200,
0xe0, 200, 0, 200,
0xff, 200, 0, 200,
0xff, 8, 50, 0,
0xff, 200, 0, 0,
0xff, 0, 0, 0,
0xff, 200, 0, 200,
0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff,
}, nil); err != nil {
panic(err)
}
}
Index ¶
- Constants
- type Devfs
- type Device
- func (d *Device) Close() error
- func (d *Device) SetBitOrder(o Order) error
- func (d *Device) SetBitsPerWord(bits int) error
- func (d *Device) SetCSChange(leaveEnabled bool) error
- func (d *Device) SetDelay(t time.Duration) error
- func (d *Device) SetMaxSpeed(speed int) error
- func (d *Device) SetMode(mode Mode) error
- func (d *Device) Tx(w, r []byte) error
- type Mode
- type Order
Examples ¶
Constants ¶
const ( Mode0 = Mode(0) Mode1 = Mode(1) Mode2 = Mode(2) Mode3 = Mode(3) )
const ( MSBFirst = Order(0) LSBFirst = Order(1) )
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Devfs ¶
type Devfs struct {
// Dev is the device to be opened.
// Device name is usually in the /dev/spidev<bus>.<chip> format.
// Required.
Dev string
// Mode is the SPI mode. SPI mode is a combination of polarity and phases.
// CPOL is the high order bit, CPHA is the low order. Pre-computed mode
// values are Mode0, Mode1, Mode2 and Mode3. The value of the mode argument
// can be overridden by the device's driver.
// Required.
Mode Mode
// MaxSpeed is the max clock speed (Hz) and can be overridden by the device's driver.
// Required.
MaxSpeed int64
}
Devfs is an SPI driver that works against the devfs. You need to have loaded the "spidev" Linux module to use this driver.
type Device ¶
type Device struct {
// contains filtered or unexported fields
}
func (*Device) SetBitOrder ¶
SetBitOrder sets the bit justification used to transfer SPI words. Valid values are MSBFirst and LSBFirst.
func (*Device) SetBitsPerWord ¶
SetBitsPerWord sets how many bits it takes to represent a word, e.g. 8 represents 8-bit words. The default is 8 bits per word.
func (*Device) SetCSChange ¶
SetCSChange sets whether to leave the chipselect enabled after a Tx.
func (*Device) SetMaxSpeed ¶
SetMaxSpeed sets the maximum clock speed in Hz. The value can be overridden by SPI device's driver.
Source Files
Directories