diff --git a/ds248x/ds248x.go b/ds248x/ds248x.go index c3bc8d7..f40a485 100644 --- a/ds248x/ds248x.go +++ b/ds248x/ds248x.go @@ -9,6 +9,7 @@ import ( "fmt" "sync" "time" + "bytes" "periph.io/x/conn/v3" "periph.io/x/conn/v3/i2c" @@ -160,6 +161,7 @@ func (d *Dev) Search(alarmOnly bool) ([]onewire.Address, error) { return onewire.Search(d, alarmOnly) } +// ChannelSelect ... func (d *Dev) ChannelSelect(ch int) (err error) { switch d.isDS248x { case isDS2482x100: @@ -184,6 +186,35 @@ func (d *Dev) ChannelSelect(ch int) (err error) { return } +// SelectedChannel ... +// On error returns 255. +func (d *Dev) SelectedChannel() (ch int) { + ch = 0 + switch d.isDS248x { + case isDS2482x100: + + case isDS2482x800: + var sch [1]byte + if err := d.i2c.Tx([]byte{cmdSetReadPtr, regCSR}, sch[:]); err != nil { + ch = 255 + return + } + csc := []byte{cscIO0r, cscIO1r, cscIO2r, cscIO3r, cscIO4r, cscIO5r, cscIO6r, cscIO7r} + ch = bytes.Index(csc, []byte{sch[0]}) + if ch < 0 { + ch = 255 + } + if ch > 7 { + ch = 255 + } + case isDS2483: + + default: + + } + return +} + // SearchTriplet performs a single bit search triplet command on the bus, waits // for it to complete and returs the outcome. // @@ -308,21 +339,6 @@ func (d *Dev) makeDev(opts *Opts) error { // register, such as the ds2482-100. if d.i2c.Tx([]byte{cmdSetReadPtr, regPCR}, nil) == nil { d.isDS248x = isDS2483 - } - - if d.i2c.Tx([]byte{cmdSetReadPtr, regCSR}, nil) == nil { - d.isDS248x = isDS2482x800 - } - - switch d.isDS248x { - case isDS2482x100: - - case isDS2482x800: - buf := []byte{cmdChannelSelect, cscIO0w} - if err := d.i2c.Tx(buf, nil); err != nil { - return fmt.Errorf("ds2482-800: error while selecting channel: %s", err) - } - case isDS2483: buf := []byte{cmdAdjPort, byte(0x00 + ((opts.ResetLow/time.Microsecond - 430) / 20 & 0x0f)), byte(0x20 + ((opts.PresenceDetect/time.Microsecond - 55) / 2 & 0x0f)), @@ -333,15 +349,21 @@ func (d *Dev) makeDev(opts *Opts) error { if err := d.i2c.Tx(buf, nil); err != nil { return fmt.Errorf("ds248x: error while setting port config values: %s", err) } - default: + } else { + if d.i2c.Tx([]byte{cmdSetReadPtr, regCSR}, nil) == nil { + d.isDS248x = isDS2482x800 + buf := []byte{cmdChannelSelect, cscIO0w} + if err := d.i2c.Tx(buf, nil); err != nil { + return fmt.Errorf("ds2482-800: error while selecting channel: %s", err) + } + } else { + d.isDS248x = isDS2482x100 + } } - return nil } -// - // shortedBusError implements error and onewire.ShortedBusError. type shortedBusError string @@ -399,3 +421,4 @@ const ( isDS2482x800 = 1 isDS2483 = 2 ) +