/
beaglebone.go
76 lines (67 loc) · 1.4 KB
/
beaglebone.go
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//Beaglebone support package.
package beaglebone
import (
"errors"
"syscall"
)
type Bone int
const (
REG_DUMMY = 0
REG_MODE = 1 // on write
REG_STATUS = 1 // on read
REG_CURR = 2
REG_STAMP = 4
REG_ADC_VAL = 6
REG_ADC_ADDR = 7
REG_ADC_DATA = 8
REG_POST = 9
REG_LEVEL = 10
)
func NewBone() (Bone, error) {
b, err := syscall.Open("/dev/logibone_mem", syscall.O_RDWR|syscall.O_SYNC, 777)
if err != nil {
return 0, err
}
return Bone(b), nil
}
func (b Bone) EndBone() {
syscall.Close(int(b))
return
}
func (b Bone) ReadInt16(addr int) (uint16, error) {
data := make([]byte, 2)
count, err := syscall.Pread(int(b), data, int64(addr))
if err != nil {
return 0, err
}
if count != 2 {
return 0, errors.New("wrong number of bytes read")
}
val := (uint16(data[1]) << 8) | uint16(data[0])
return val, nil
}
func (b Bone) WriteInt16(addr int, val uint16) error {
data := make([]byte, 2)
data[0] = byte((val) & 0x00FF)
data[1] = byte((val >> 8) & 0x00FF)
count, err := syscall.Pwrite(int(b), data, int64(addr))
if err != nil {
return err
}
if count != 2 {
return errors.New("wrong number of bytes written")
}
return nil
}
func (b Bone) ReadInt32(addr int) (uint32, error) {
msb, err := b.ReadInt16(addr)
if err != nil {
return 0, err
}
lsb, err := b.ReadInt16(addr + 1)
if err != nil {
return 0, err
}
val := (uint32(msb) << 16) | uint32(lsb)
return val, nil
}