display-test/pkg/mt12864a/mt12864a.go
2024-09-02 13:11:36 +03:00

374 lines
8.7 KiB
Go

package mt12864a
import (
"fmt"
"io"
"log"
"time"
"github.com/stianeikeland/go-rpio/v4"
)
const (
enablePrintPins = false
adressWriteTimeout = 140 * time.Nanosecond
dataStrobeTimeout = 250 * time.Nanosecond // (Data transfer)
maxWaitCycles = 100
)
type mt12864a struct {
logger *log.Logger
// GPIO pins
pinA0 rpio.Pin
pinRW rpio.Pin
pinE rpio.Pin
pinDB0 rpio.Pin
pinDB1 rpio.Pin
pinDB2 rpio.Pin
pinDB3 rpio.Pin
pinDB4 rpio.Pin
pinDB5 rpio.Pin
pinDB6 rpio.Pin
pinDB7 rpio.Pin
pinE1 rpio.Pin
pinE2 rpio.Pin
pinRES rpio.Pin
}
type Device interface {
PowerOn() error
SetPixel(x, y byte, c bool) error
WriteCodeL(c byte) error
WriteCodeR(c byte) error
WriteDataL(b byte) error
WriteDataR(b byte) error
ReadDataL() (byte, error)
ReadDataR() (byte, error)
ReadStatus(l, r rpio.State) byte
io.Closer
}
func New(logger *log.Logger) (Device, error) {
rpio.Open()
d := mt12864a{
logger: logger,
pinA0: rpio.Pin(18),
pinRW: rpio.Pin(17),
pinE: rpio.Pin(27),
pinDB0: rpio.Pin(22),
pinDB1: rpio.Pin(10),
pinDB2: rpio.Pin(9), // From 21
pinDB3: rpio.Pin(11),
pinDB4: rpio.Pin(12),
pinDB5: rpio.Pin(16), // From 32
pinDB6: rpio.Pin(20), // From 31
pinDB7: rpio.Pin(13), // From 33
// Reverted
// pinDB7: rpio.Pin(15),
// pinDB6: rpio.Pin(19),
// pinDB5: rpio.Pin(21),
// pinDB4: rpio.Pin(23),
// pinDB3: rpio.Pin(27),
// pinDB2: rpio.Pin(32),
// pinDB1: rpio.Pin(31),
// pinDB0: rpio.Pin(33),
pinE1: rpio.Pin(19),
pinE2: rpio.Pin(26),
pinRES: rpio.Pin(21),
}
d.AllOutput()
return &d, nil
}
func (d *mt12864a) Close() error {
return rpio.Close()
}
func (d *mt12864a) SetPixel(x, y byte, c bool) error {
// var c8 byte
// var mask byte
// Check bounds
if x > 127 || y > 63 {
return fmt.Errorf("positions out of bounds")
}
if x < 64 { // Left crystal
d.WriteCodeL(0xB8 | (y >> 3)) // Set page
d.WriteCodeL(0x40 | x) // Set addr
// c8=ReadDataL(); // ?? ok
// c8=ReadDataL(); // Read byte
// m8=1<<(y&0x07);//Вычислить маску нужного бита в байте
// if (c==1) //Зажигать точку?
// c8|=m8//Установить нужный бит в байте
// else //Или гасить точку?
// c8&=~m8;//Сбросить нужный бит в байте
// WriteCodeL(0x40|x);//Снова установить адрес нужного байта
d.WriteDataL(0x34) // Write byte
}
return nil
}
func (d *mt12864a) PowerOn() error {
d.logger.Println(d.ReadStatus(1, 0)) // Should be 0
d.logger.Println("Reset")
d.pinE.Low()
d.pinRES.Low()
time.Sleep(time.Microsecond)
d.logger.Println(d.ReadStatus(1, 0)) // Should be 48 (power off and reset)
d.pinRES.High()
time.Sleep(10 * time.Microsecond)
d.logger.Println(d.ReadStatus(1, 0)) // Should be 32 (power off)
// Module is reset and should be turned off
if d.ReadStatus(1, 0) == 0 || d.ReadStatus(0, 1) == 0 {
return fmt.Errorf("no response from display(or it is possible that it is turned on but...)")
}
d.logger.Println("Power on")
d.PrintPins()
d.logger.Println("Top line to 0")
d.WriteCodeL(0xC0) // Top line to 0
d.WriteCodeR(0xC0) // Top line to 0
d.logger.Println("Display on")
d.WriteCodeL(0x3F) // Display on
d.WriteCodeR(0x3F) // Display on
// Check that crystals are turned on
if (d.ReadStatus(1, 0) & (1 << 5)) != 0 {
return fmt.Errorf("Left cristal is still off")
}
if (d.ReadStatus(0, 1) & (1 << 5)) != 0 {
return fmt.Errorf("Right cristal is still off")
}
return nil
}
// Write codes
func (d *mt12864a) WriteCodeL(c byte) error {
return d.writeByte(c, 0, 1, 0)
}
func (d *mt12864a) WriteCodeR(c byte) error {
return d.writeByte(c, 0, 0, 1)
}
// Write data as byte
func (d *mt12864a) WriteDataL(b byte) error {
return d.writeByte(b, 1, 1, 0)
}
func (d *mt12864a) WriteDataR(b byte) error {
return d.writeByte(b, 1, 0, 1)
}
// Read data
func (d *mt12864a) ReadDataL() (byte, error) {
return d.readByte(1, 1, 0)
}
func (d *mt12864a) ReadDataR() (byte, error) {
return d.readByte(1, 0, 1)
}
// Low level functions
func (d *mt12864a) writeByte(b byte, cd, l, r rpio.State) error {
// d.logger.Println("Write byte", b, cd, l, r)
if l == rpio.High && r == rpio.High {
d.logger.Println("L and R are high!!!")
return fmt.Errorf("cannot write left and right at the same times")
}
if err := d.waitReady(l, r); err != nil {
return fmt.Errorf("wait ready: %w", err)
}
d.busOutput()
d.pinRW.Low() // We write
d.pinA0.Write(cd)
d.pinE1.Write(l) // Select cristals
d.pinE2.Write(r) // Select cristals
// Write bus
d.pinDB0.Write(rpio.State((b >> 0) & 1))
d.pinDB1.Write(rpio.State((b >> 1) & 1))
d.pinDB2.Write(rpio.State((b >> 2) & 1))
d.pinDB3.Write(rpio.State((b >> 3) & 1))
d.pinDB4.Write(rpio.State((b >> 4) & 1))
d.pinDB5.Write(rpio.State((b >> 5) & 1))
d.pinDB6.Write(rpio.State((b >> 6) & 1))
d.pinDB7.Write(rpio.State((b >> 7) & 1))
// Strobe start
d.pinE.High()
time.Sleep(dataStrobeTimeout)
// Strobe end
d.pinE.Low()
time.Sleep(time.Millisecond - dataStrobeTimeout - adressWriteTimeout)
return nil
}
func (d *mt12864a) readByte(cd, l, r rpio.State) (byte, error) {
if l == rpio.High && r == rpio.High {
d.logger.Println("L and R are high!!!")
return 0, fmt.Errorf("cannot ready left and right at the same time")
}
// Setup
var b byte
if err := d.waitReady(l, r); err != nil {
return 0, fmt.Errorf("wait ready: %w", err)
}
d.busOutput()
d.pinRW.High() // We write
d.pinA0.Write(cd)
d.pinE1.Write(l) // Select cristals
d.pinE2.Write(r) // Select cristals
// Strobe start
d.pinE.High()
time.Sleep(dataStrobeTimeout)
// Read
b = uint8(d.pinDB0.Read()) |
(uint8(d.pinDB1.Read()) << 1) |
(uint8(d.pinDB2.Read()) << 2) |
(uint8(d.pinDB3.Read()) << 3) |
(uint8(d.pinDB4.Read()) << 4) |
(uint8(d.pinDB5.Read()) << 5) |
(uint8(d.pinDB6.Read()) << 6) |
(uint8(d.pinDB7.Read()) << 7)
// Strobe end
d.pinE.Low()
time.Sleep(time.Millisecond - dataStrobeTimeout - adressWriteTimeout)
return b, nil
}
// Wait, checking status byte
func (d *mt12864a) waitReady(l, r rpio.State) error {
//d.logger.Println("Wait ready", l, r)
d.busInput() // Set bus to input
d.pinRW.High() // We read
d.pinA0.Low() // Status
d.pinE1.Write(l) // Select cristals
d.pinE2.Write(r) // Select cristals
time.Sleep(adressWriteTimeout)
// Strobe start
d.pinE.High()
time.Sleep(dataStrobeTimeout)
// Wait status flag drop
ok := false
d.busInput() // Set bus to input
for counter := 0; counter < maxWaitCycles; counter++ {
if d.pinDB7.Read() != rpio.High {
//d.logger.Printf("BUS:%d%d%d%d%d%d%d%d\n", d.pinDB0.Read(), d.pinDB1.Read(), d.pinDB2.Read(), d.pinDB3.Read(), d.pinDB4.Read(), d.pinDB5.Read(), d.pinDB6.Read(), d.pinDB7.Read())
ok = true
break
}
}
if !ok {
return fmt.Errorf("busy timeout")
}
// Strobe end
d.pinE.Low()
time.Sleep(time.Millisecond - dataStrobeTimeout - adressWriteTimeout)
// d.logger.Println("Ready")
return nil
}
func (d *mt12864a) ReadStatus(l, r rpio.State) byte {
d.busInput() // Set bus to input
d.pinRW.High() // We read
d.pinA0.Low() // Status
d.pinE1.Write(l) // Select cristals
d.pinE2.Write(r) // Select cristals
time.Sleep(adressWriteTimeout)
// Strobe start
d.pinE.High()
time.Sleep(dataStrobeTimeout)
d.busInput()
var b byte = uint8(d.pinDB0.Read()) |
(uint8(d.pinDB1.Read()) << 1) |
(uint8(d.pinDB2.Read()) << 2) |
(uint8(d.pinDB3.Read()) << 3) |
(uint8(d.pinDB4.Read()) << 4) |
(uint8(d.pinDB5.Read()) << 5) |
(uint8(d.pinDB6.Read()) << 6) |
(uint8(d.pinDB7.Read()) << 7)
// Strobe end
d.pinE.Low()
time.Sleep(time.Millisecond - dataStrobeTimeout - adressWriteTimeout)
return b
}
func (d *mt12864a) PrintPins() {
if !enablePrintPins {
return
}
d.AllInput()
d.logger.Printf("A0:%d RW:%d E:%d BUS:%d%d%d%d%d%d%d%d E1:%d E2:%d RES:%d\n", d.pinA0.Read(), d.pinRW.Read(), d.pinE.Read(), d.pinDB0.Read(), d.pinDB1.Read(), d.pinDB2.Read(), d.pinDB3.Read(), d.pinDB4.Read(), d.pinDB5.Read(), d.pinDB6.Read(), d.pinDB7.Read(), d.pinE1.Read(), d.pinE2.Read(), d.pinRES.Read())
d.AllOutput()
}
func (d *mt12864a) AllOutput() {
d.pinA0.Output()
d.pinRW.Output()
d.pinE.Output()
d.pinE1.Output()
d.pinE2.Output()
d.pinRES.Output()
d.busOutput()
}
func (d *mt12864a) AllInput() {
d.pinA0.Input()
d.pinRW.Input()
d.pinE.Input()
d.pinE1.Input()
d.pinE2.Input()
d.pinRES.Input()
d.busInput()
}
// Set bus pins to output
func (d *mt12864a) busOutput() {
d.pinDB0.Output()
d.pinDB1.Output()
d.pinDB2.Output()
d.pinDB3.Output()
d.pinDB4.Output()
d.pinDB5.Output()
d.pinDB6.Output()
d.pinDB7.Output()
}
func (d *mt12864a) busInput() {
d.pinDB0.Input()
d.pinDB1.Input()
d.pinDB2.Input()
d.pinDB3.Input()
d.pinDB4.Input()
d.pinDB5.Input()
d.pinDB6.Input()
d.pinDB7.Input()
}