/
lowlevel.go
125 lines (106 loc) · 2.79 KB
/
lowlevel.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
/*
capsulates all SPI and gpio pin operations
*/
package main
import (
"fmt"
"time"
"periph.io/x/conn/v3/gpio"
"periph.io/x/conn/v3/gpio/gpioreg"
"periph.io/x/conn/v3/physic"
"periph.io/x/conn/v3/spi"
"periph.io/x/conn/v3/spi/spireg"
"periph.io/x/host/v3"
)
type LowLevelInterfacing interface {
Send(command byte, pars ...byte) error //Command and data
Reset() error
Idle() bool //true if is idle
}
type EPD0213LowLevel struct {
readyPin gpio.PinIO //BCM24
resetPin gpio.PinIO //BCM17
dataModePin gpio.PinIO //BCM25
spiConn spi.Conn //*spi.Device
}
func InitEPD0213LowLevel(spiDeviceFileName string, readyPinName string, resetPinName string, dataModePinName string) (EPD0213LowLevel, error) {
if !fileExists(spiDeviceFileName) {
return EPD0213LowLevel{}, fmt.Errorf("SPI device file %v is missing", spiDeviceFileName)
}
_, err := host.Init()
if err != nil {
return EPD0213LowLevel{}, err
}
p, errSpi := spireg.Open(spiDeviceFileName)
if errSpi != nil {
return EPD0213LowLevel{}, fmt.Errorf("spi %v error %v", spiDeviceFileName, errSpi.Error())
}
c, errSpiConnect := p.Connect(physic.MegaHertz, spi.Mode0, 8)
if errSpiConnect != nil {
return EPD0213LowLevel{}, errSpiConnect
}
result := EPD0213LowLevel{
spiConn: c,
readyPin: gpioreg.ByName(readyPinName),
resetPin: gpioreg.ByName(resetPinName),
dataModePin: gpioreg.ByName(dataModePinName),
}
if result.readyPin == nil {
return result, fmt.Errorf("readyPin fail")
}
if result.resetPin == nil {
return result, fmt.Errorf("resetPin fail")
}
if result.dataModePin == nil {
return result, fmt.Errorf("dataPin fail")
}
return result, nil
}
func (p *EPD0213LowLevel) Send(command byte, pars ...byte) error { //Command and data
onebyteresp := make([]byte, 1)
dataModePinClearErr := p.dataModePin.Out(gpio.Low)
if dataModePinClearErr != nil {
return dataModePinClearErr
}
spiErr := p.spiConn.Tx([]byte{command}, onebyteresp)
if spiErr != nil {
return spiErr
}
if 0 < len(pars) {
//DC=1
dataModePinSetErr := p.dataModePin.Out(gpio.High)
if dataModePinSetErr != nil {
return dataModePinSetErr
}
//CS=0
for _, data := range pars {
spiErr := p.spiConn.Tx([]byte{data}, onebyteresp)
if spiErr != nil {
return spiErr
}
}
}
//CS=1 //SPI controls CS?
return nil
}
func (p *EPD0213LowLevel) Reset() error {
err := p.resetPin.Out(gpio.High)
if err != nil {
return err
}
time.Sleep(200 * time.Millisecond) //Needed if was low?
err = p.resetPin.Out(gpio.Low)
if err != nil {
return err
}
time.Sleep(200 * time.Millisecond)
err = p.resetPin.Out(gpio.High)
if err != nil {
return err
}
time.Sleep(200 * time.Millisecond) //Stupid? or time for recover
return nil
}
func (p *EPD0213LowLevel) Idle() bool {
return p.readyPin.Read() == gpio.Low
} //true if is idle