Display text on TFT screen sent from PC.
Arduino is Nano or Uno. TFT screen is 1.8" driver ST7735. Connected to PC via USB. Color and size are selectable.
Arduino is Nano or Uno. TFT screen is 1.8" driver ST7735. Connected to PC via USB. Color and size are selectable.
B4X:
' TFT module with ST7735 driver
' 1 LED 3.3 V or 5V via 47 ohm
' 2 SCK 13
' 3 SDA 11
' 4 A0 Or DC 9
' 5 RESET 8
' 6 CS 10
' 7 GND GND
' 8 VCC 5 V
Sub Process_Globals
Public Serial1 As Serial
Private astream As AsyncStreams
Public CS As Pin
Public DC As Pin
Public SDA As Pin
Public SCK As Pin
Public RST As Pin
Public BLACK As UInt=0x0000
Public BLUE As UInt=0x01F
Public RED As UInt=0xF800
Public GREEN As UInt=0x07E0
Public CYAN As UInt=0x07FF
Public MAGENTA As UInt=0xF81F
Public YELLOW As UInt=0xFFE0
Public WHITE As UInt=0xFFFF
Private cColor As UInt
Private spires, spidata As Byte
Private cx=2, cy=2, csize=1 As Byte
End Sub
Private Sub AppStart
Serial1.Initialize(9600)
astream.Initialize(Serial1.Stream, "astream_NewData", Null)
CS.Initialize(10, CS.MODE_OUTPUT)
DC.Initialize(9, DC.MODE_OUTPUT)
SCK.Initialize(13, SCK.MODE_OUTPUT)
RST.Initialize(8, RST.MODE_OUTPUT)
SDA.Initialize(11, SDA.MODE_OUTPUT)
RunNative ("set_spi",Null)
TFTinit
rectan(0,0,159,127,WHITE) 'clear screen
End Sub
Sub astream_NewData (Buffer() As Byte)
If Buffer.Length > 0 Then
Select Buffer(0)
Case 0
rectan(0,0,159,127,WHITE) 'clear screen
cx=2
cy=2
Case 1
csize=1
Case 2
csize=2
Case 3
csize=3
Case 4
csize=4
Case 5
cColor=0x00
Case 6
cColor=0xF800
Case 7
cColor=0x07E0
Case 8
cColor=0x01F
Case Else
drawC(cx,cy,Buffer(0),cColor,csize)
cx=cx+(csize*6)
If cx>157 Then
cx=2
cy=cy+(csize*9)
End If
If cy>125 Then cy=2
End Select
End If
End Sub
'draw char
Sub drawC(x As Byte, y As Byte, c As Byte, color As UInt, size As Byte)
Dim i, j, line As Byte
Private font() As Byte = Array As Byte( _
0x00, 0x00, 0x00, 0x00, 0x00, _ ' (space)
0x00, 0x00, 0x5F, 0x00, 0x00, _ ' !
0x00, 0x07, 0x00, 0x07, 0x00, _ ' "
0x14, 0x7F, 0x14, 0x7F, 0x14, _ ' #
0x24, 0x2A, 0x7F, 0x2A, 0x12, _ ' $
0x23, 0x13, 0x08, 0x64, 0x62, _ ' %
0x36, 0x49, 0x55, 0x22, 0x50, _ ' &
0x00, 0x05, 0x03, 0x00, 0x00, _ ' '
0x00, 0x1C, 0x22, 0x41, 0x00, _ ' (
0x00, 0x41, 0x22, 0x1C, 0x00, _ ' )
0x08, 0x2A, 0x1C, 0x2A, 0x08, _ ' *
0x08, 0x08, 0x3E, 0x08, 0x08, _ ' +
0x00, 0x50, 0x30, 0x00, 0x00, _ ' ,
0x08, 0x08, 0x08, 0x08, 0x08, _ ' -
0x00, 0x60, 0x60, 0x00, 0x00, _ ' .
0x20, 0x10, 0x08, 0x04, 0x02, _ ' /
0x3E, 0x51, 0x49, 0x45, 0x3E, _ ' 0
0x00, 0x42, 0x7F, 0x40, 0x00, _ ' 1
0x72, 0x49, 0x49, 0x49, 0x46, _
0x21, 0x41, 0x49, 0x4D, 0x33, _
0x18, 0x14, 0x12, 0x7F, 0x10, _
0x27, 0x45, 0x45, 0x45, 0x39, _ ' 5
0x3C, 0x4A, 0x49, 0x49, 0x31, _
0x41, 0x21, 0x11, 0x09, 0x07, _
0x36, 0x49, 0x49, 0x49, 0x36, _
0x46, 0x49, 0x49, 0x29, 0x1E, _ ' 9
0x00, 0x36, 0x36, 0x00, 0x00, _ ' :
0x00, 0x56, 0x36, 0x00, 0x00, _ ' ;
0x00, 0x08, 0x14, 0x22, 0x41, _ ' <
0x14, 0x14, 0x14, 0x14, 0x14, _ ' =
0x41, 0x22, 0x14, 0x08, 0x00, _ ' >
0x02, 0x01, 0x51, 0x09, 0x06, _ ' ?
0x32, 0x49, 0x79, 0x41, 0x3E, _ ' @
0x7E, 0x11, 0x11, 0x11, 0x7E, _ ' A
0x7F, 0x49, 0x49, 0x49, 0x36, _ ' B
0x3E, 0x41, 0x41, 0x41, 0x22, _ ' C
0x7F, 0x41, 0x41, 0x22, 0x1C, _ ' D
0x7F, 0x49, 0x49, 0x49, 0x41, _ ' E
0x7F, 0x09, 0x09, 0x01, 0x01, _ ' F
0x3E, 0x41, 0x41, 0x51, 0x32, _ ' G
0x7F, 0x08, 0x08, 0x08, 0x7F, _ ' H
0x00, 0x41, 0x7F, 0x41, 0x00, _ ' I
0x20, 0x40, 0x41, 0x3F, 0x01, _ ' J
0x7F, 0x08, 0x14, 0x22, 0x41, _ ' K
0x7F, 0x40, 0x40, 0x40, 0x40, _ ' L
0x7F, 0x02, 0x04, 0x02, 0x7F, _ ' M
0x7F, 0x04, 0x08, 0x10, 0x7F, _ ' N
0x3E, 0x41, 0x41, 0x41, 0x3E, _ ' O
0x7F, 0x09, 0x09, 0x09, 0x06, _ ' P
0x3E, 0x41, 0x51, 0x21, 0x5E, _ ' Q
0x7F, 0x09, 0x19, 0x29, 0x46, _ ' R
0x46, 0x49, 0x49, 0x49, 0x31, _ ' S
0x01, 0x01, 0x7F, 0x01, 0x01, _ ' T
0x3F, 0x40, 0x40, 0x40, 0x3F, _ ' U
0x1F, 0x20, 0x40, 0x20, 0x1F, _ ' V
0x7F, 0x20, 0x18, 0x20, 0x7F, _ ' W
0x63, 0x14, 0x08, 0x14, 0x63, _ ' X
0x03, 0x04, 0x78, 0x04, 0x03, _ ' Y
0x61, 0x51, 0x49, 0x45, 0x43, _ ' Z
0x00, 0x00, 0x7F, 0x41, 0x41, _ ' [
0x02, 0x04, 0x08, 0x10, 0x20, _ ' "\"
0x41, 0x41, 0x7F, 0x00, 0x00, _ ' ]
0x04, 0x02, 0x01, 0x02, 0x04, _ ' ^
0x40, 0x40, 0x40, 0x40, 0x40, _ ' _
0x00, 0x01, 0x02, 0x04, 0x00, _ ' `
0x20, 0x54, 0x54, 0x54, 0x78, _ ' a
0x7F, 0x48, 0x44, 0x44, 0x38, _ ' b
0x38, 0x44, 0x44, 0x44, 0x20, _ ' c
0x38, 0x44, 0x44, 0x48, 0x7F, _ ' d
0x38, 0x54, 0x54, 0x54, 0x18, _ ' e
0x08, 0x7E, 0x09, 0x01, 0x02, _ ' f
0x08, 0x14, 0x54, 0x54, 0x3C, _ ' g
0x7F, 0x08, 0x04, 0x04, 0x78, _ ' h
0x00, 0x44, 0x7D, 0x40, 0x00, _ ' i
0x20, 0x40, 0x44, 0x3D, 0x00, _ ' j
0x00, 0x7F, 0x10, 0x28, 0x44, _ ' k
0x00, 0x41, 0x7F, 0x40, 0x00, _ ' l
0x7C, 0x04, 0x18, 0x04, 0x78, _ ' m
0x7C, 0x08, 0x04, 0x04, 0x78, _ ' n
0x38, 0x44, 0x44, 0x44, 0x38, _ ' o
0x7C, 0x14, 0x14, 0x14, 0x08, _ ' p
0x08, 0x14, 0x14, 0x18, 0x7C, _ ' q
0x7C, 0x08, 0x04, 0x04, 0x08, _ ' r
0x48, 0x54, 0x54, 0x54, 0x20, _ ' s
0x04, 0x3F, 0x44, 0x40, 0x20, _ ' t
0x3C, 0x40, 0x40, 0x20, 0x7C, _ ' u
0x1C, 0x20, 0x40, 0x20, 0x1C, _ ' v
0x3C, 0x40, 0x30, 0x40, 0x3C, _ ' w
0x44, 0x28, 0x10, 0x28, 0x44, _ ' x
0x0C, 0x50, 0x50, 0x50, 0x3C, _ ' y
0x44, 0x64, 0x54, 0x4C, 0x44, _ ' z
0x00, 0x08, 0x36, 0x41, 0x00, _ ' {
0x00, 0x00, 0x7F, 0x00, 0x00, _ ' |
0x00, 0x41, 0x36, 0x08, 0x00, _ ' }
0x08, 0x08, 0x2A, 0x1C, 0x08, _ ' ->
0x08, 0x1C, 0x2A, 0x08, 0x08, _ ' <-
0x00, 0x06, 0x09, 0x09, 0x06) ' degree symbol
For i=0 To 5
If i = 5 Then
line = 0
Else
line = font(((c-32)*5)+i)
For j = 0 To 7
If (line Mod 2)=1 Then
If size = 1 Then
pixel(x+i, y+j, color)
Else
rectan(x+(i*size), y+(j*size), x+(i*size)+size, y+(j*size)+size, color)
End If
End If
line = line / 2
Next
End If
Next
End Sub
Sub spi(data As Byte) 'send byte over spi
spidata=data
RunNative ("spi",Null)
Return
End Sub
Sub command(cmd As Byte)
DC.DigitalWrite(False) 'command Mode
CS.DigitalWrite(False) 'Select the LCD (active low)
spi(cmd) 'set up data on bus
CS.DigitalWrite(True) 'Deselect LCD (active low)
End Sub
Sub send_data(data As Byte)
DC.DigitalWrite(True) 'data mode
CS.DigitalWrite(False) 'Select the LCD (active low)
spi(data) 'set up data on bus
CS.DigitalWrite(True) 'Deselect LCD (active low)
End Sub
Sub TFTinit
Dim i As Byte
RST.DigitalWrite(True) 'hardware reset
Delay(200)
RST.DigitalWrite(False)
Delay(10)
RST.DigitalWrite(True)
Delay(10)
command(0x01) 'sw reset
Delay(200)
command(0x11) ' Sleep out
Delay(200)
command(0x3A) 'color mode
send_data(0x05) '16 bits
'send_data(0x06) '18 bits
command(0x36) 'Memory access ctrl (directions)
send_data(0x60) '0B1100000=0x60
'send_data(0x08) '0x48=left to right,BRG,horizontal 0x40=vertical,RGB
'command(0x21) 'color inversion on
command(0x2D) 'color look up table
send_data(0)
For i = 1 To 31
send_data(i * 2)
Next
For i = 0 To 63
send_data(i)
Next
send_data(0)
For i = 1 To 31
send_data(i * 2)
Next
command(0x13) 'Normal display on
command(0x29) 'Main screen turn on
End Sub
Sub area(x0 As Byte, y0 As Byte, x1 As Byte, y1 As Byte)
command(0x2A) 'Column addr set
send_data(0x00)
send_data(x0) ' XSTART
send_data(0x00)
send_data(x1) ' XEND
command(0x2B) 'Row addr set
send_data(0x00)
send_data(y0) ' YSTART
send_data(0x00)
send_data(y1) ' YEND
command(0x2C) 'write To RAM
End Sub
Sub rectan(x0 As Byte, y0 As Byte, x1 As Byte, y1 As Byte, color As UInt)
Dim i As Int
area(x0,y0,x1,y1)
For i=(y1 - y0 + 1) * (x1 - x0 + 1) To 0 Step -1
DC.DigitalWrite(True) ' data mode
CS.DigitalWrite(False)
spi(color / 256)
spi(color Mod 256)
CS.DigitalWrite(True)
Next
End Sub
Sub pixel(x As Byte, y As Byte, color As UInt)
area(x,y,x+1,y+1)
send_data(color / 256)
send_data(color Mod 256)
End Sub
#if C
void spi(B4R::Object* o)
{
SPDR = b4r_main::_spidata; // Start transmission
while (!(SPSR & _BV(SPIF))); // Wait For transmission To complete
b4r_main::_spires = SPDR; // received byte
}
#End if
#if C
void set_spi(B4R::Object* o)
{
SPCR = 0B1011100; // Enable SPI, Master, mode3, set clock rate fck/4 = 4MHz
//SPSR = 1; //set clock rate fck/2=2MHz
}
#End if
B4X:
Sub Process_Globals
Private fx As JFX
Private MainForm As Form
Private xui As XUI
Private sp As Serial
Private astream As AsyncStreams
Private tmr1 As Timer
Private cmb1 As ComboBox
Private btnOpen As Button
Private Label1 As Label
Private tc(), tl, ti=0, outB(1) As Byte
Private text1 As TextArea
Private btnClear As Button
Private btnSend As Button
Private cmbSize As ComboBox
Private cmbColor As ComboBox
End Sub
Sub AppStart (Form1 As Form, Args() As String)
MainForm = Form1
MainForm.RootPane.LoadLayout("Layout1")
MainForm.Show
sp.Initialize("")
cmb1.Items.AddAll(sp.ListPorts)
tmr1.Initialize("tmr1",50)
tmr1.Enabled=False
cmbSize.Items.AddAll(Array As String("1", "2", "3", "4"))
cmbColor.Items.AddAll(Array As String("BLACK", "RED", "GREEN", "BLUE"))
End Sub
Sub cmb1_SelectedIndexChanged(Index As Int, Value As Object)
btnOpen.Enabled = Index > -1 'enable the button if there is a selected item
End Sub
Sub btnOpen_Action
sp.Open(cmb1.Value)
sp.SetParams(9600,8,1,0)
astream.Initialize(sp.GetInputStream, sp.GetOutputStream, "astream")
btnOpen.Enabled = False
Label1.Text = "Port Opened"
btnSend.Enabled=True
cmbSize.Enabled=True
cmbColor.Enabled=True
End Sub
Sub cmbSize_SelectedIndexChanged(Index As Int, Value As Object)
outB(0)=cmbSize.Value
astream.Write(outB)
End Sub
Sub cmbColor_SelectedIndexChanged(Index As Int, Value As Object)
outB(0)=cmbColor.SelectedIndex + 5
astream.Write(outB)
End Sub
Sub btnSend_Action
tc=text1.Text.GetBytes("UTF8")
tl=tc.Length
If tc.Length>0 Then tmr1.Enabled=True
End Sub
Sub tmr1_Tick
outB(0)=tc(ti)
astream.Write(outB)
ti=ti+1
If ti > (tl-1) Then
tmr1.Enabled=False
ti=0
End If
End Sub
Sub btnClear_Action
outB(0)=0
astream.Write(outB)
End Sub
Sub MainForm_Closed
'sp.Close
End Sub
Sub AStream_NewData (Buffer() As Byte)
End SubAttachments
Last edited:
