User avatar
voynich
Posts: 10
Joined: Sun Oct 06, 2013 11:38 pm

3.5 TFT hvga module interface

Mon Oct 07, 2013 5:13 am

I've followed notro's wiki but can't get the module initialised.The dmesg errors [ 363.350409] fb_hello: Unknown symbol fbtft_remove_common (err 0)
[ 363.350483] fb_hello: Unknown symbol fbtft_probe_common (err 0)
[ 410.026274] fbtft_device: disagrees about version of symbol fbtft_write_gpio16_wr_latched
[ 410.026311] fbtft_device: Unknown symbol fbtft_write_gpio16_wr_latched (err -22)
[ 410.026435] fbtft_device: Unknown symbol fbtft_dbg_hex (err 0)
I don't know about the controller but the seller of send me a demo code for 8051 mc

notro
Posts: 695
Joined: Tue Oct 16, 2012 6:21 pm
Location: Drammen, Norway

Re: 3.5 TFT hvga module interface

Mon Oct 07, 2013 10:08 am

I guess you use insmod to load the modules, but that doesn't load the dependencies. Do modprobe fbtft first.

User avatar
voynich
Posts: 10
Joined: Sun Oct 06, 2013 11:38 pm

Re: 3.5 TFT hvga module interface

Tue Oct 08, 2013 12:09 am

I used your's git wiki.
As there is no driver in fbtft image for 3.5" tft module.
So I developed a new one based on your development wiki.
I have reflashed the sd card with provided fbtft image almost 10 times and followed your wiki again and again but always got struck on this command
sudo insmod ~/linux/drivers/video/fbtft/fb_hello.ko
Error: could not insert module /home/pi/linux/drivers/video/fbtft/fb_hello.ko: Unknown symbol in module

the dmesg error
[ 2380.098147] fb_hello: Unknown symbol fbtft_remove_common (err 0)
[ 2380.098217] fb_hello: Unknown symbol fbtft_probe_common (err 0)
I followed your wiki from word to word
So I always use modprobe before insmod.
Not a single error till i use insmod command.
I checked again and again the codes i add to following
1.static struct fbtft_device_display displays[](i add the device after device tm022hdh26)
and
2./linux/drivers/video/fbtft/fb_hello.c
3./linux/drivers/video/fbtft/Makefile
4./linux/drivers/video/fbtft/Kconfig
But everything is exact to the wiki.
The link for the demo code the seller provided:
http://sdrv.ms/16uiGwc

notro
Posts: 695
Joined: Tue Oct 16, 2012 6:21 pm
Location: Drammen, Norway

Re: 3.5 TFT hvga module interface

Tue Oct 08, 2013 8:06 pm

voynich wrote:I used your's git wiki.
As there is no driver in fbtft image for 3.5" tft module.
So I developed a new one based on your development wiki.
I have reflashed the sd card with provided fbtft image almost 10 times and followed your wiki again and again but always got struck on this command
sudo insmod ~/linux/drivers/video/fbtft/fb_hello.ko
Error: could not insert module /home/pi/linux/drivers/video/fbtft/fb_hello.ko: Unknown symbol in module
What is the output of lsmod

User avatar
voynich
Posts: 10
Joined: Sun Oct 06, 2013 11:38 pm

Re: 3.5 TFT hvga module interface

Wed Oct 09, 2013 12:03 am

lsmod output:

Code: Select all

Module                  Size  Used by
fbtft                  26108  0
syscopyarea             3136  1 fbtft
sysfillrect             3302  1 fbtft
sysimgblt               2195  1 fbtft
fb_sys_fops             1404  1 fbtft
snd_bcm2835            16273  0
snd_pcm                78130  1 snd_bcm2835
snd_page_alloc          5129  1 snd_pcm
snd_seq                53349  0
snd_seq_device          6454  1 snd_seq
snd_timer              19946  2 snd_pcm,snd_seq
snd                    58506  5 snd_bcm2835,snd_timer,snd_pcm,snd_seq,snd_seq_device
spidev                  5240  0
leds_gpio               2197  0
led_class               3592  1 leds_gpio
spi_bcm2708             5414  0
Interfacing:

Code: Select all

3V3           3V3
MOSI        GPIO10
CS            GPIO8
SCLK        GPIO11
BL             GPIO18
GND         GND
RS            GPIO24
RST          GPIO25
Also tried with BL,RST disconnected.

notro
Posts: 695
Joined: Tue Oct 16, 2012 6:21 pm
Location: Drammen, Norway

Re: 3.5 TFT hvga module interface

Thu Oct 10, 2013 12:11 pm

Well, I don't know what the problem might be. The last time I tested that guide was 3 weeks ago. I don't have time to test it at the moment. If you can't make it work, another solution is to do a full kernel build.
This is how I have built this particular image: https://github.com/notro/fbtft/wiki/FBT ... ld-process
Here's another build guide: https://github.com/notro/fbtft/wiki/Bui ... ft-drivers

User avatar
voynich
Posts: 10
Joined: Sun Oct 06, 2013 11:38 pm

Re: 3.5 TFT hvga module interface

Thu Oct 17, 2013 7:13 am

I'd initialized the display,but it is all time displaying black all over screen.
i tried to start x on module with command

Code: Select all

FRAMEBUFFER=/dev/fb1 startx

but the screen is always black
how do i start console or anything on the module.
I'd enabled the module to run on startup
and also edited the /boot/cmdline.txt for displaying console.
but again it is all black.
and also how do I change the CDIV values.
Some information:

Code: Select all

$ lsmod:
Module                  Size  Used by
fb_hello                1982  0 
fbtft_device           21758  0 
fbtft                  31081  2 fb_hello,fbtft_device
syscopyarea             3136  1 fbtft
sysfillrect             3302  1 fbtft
sysimgblt               2195  1 fbtft
fb_sys_fops             1404  1 fbtft
spidev                  5240  0 
spi_bcm2708             5414  0 
snd_bcm2835            16273  0 
snd_pcm                78130  1 snd_bcm2835
snd_page_alloc          5129  1 snd_pcm
snd_seq                53349  0 
snd_seq_device          6454  1 snd_seq
snd_timer              19946  2 snd_pcm,snd_seq
snd                    58506  5 snd_bcm2835,snd_timer,snd_pcm,snd_seq,snd_seq_device
leds_gpio               2197  0 
led_class               3592  1 leds_gpio

$ find /lib/modules/`uname -r` -name '*.ko' | grep tft
/lib/modules/3.6.11+/kernel/net/netfilter/nf_conntrack_tftp.ko
/lib/modules/3.6.11+/kernel/net/ipv4/netfilter/nf_nat_tftp.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/sainsmart32fb.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/nokia3310fb.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/fbtft.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/itdb28fb.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/fb_ssd1289.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/adafruit18fb.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/fb_ili9325.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/ssd1351fb.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/fb_hello.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/fb_pcd8544.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/fb_watterott.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/fb_ssd1351.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/fb_hx8340bn.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/adafruit22fb.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/flexfb.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/ili9341fb.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/fb_ili9320.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/fbtft_device.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/r61505ufb.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/fb_hx8347d.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/fb_st7735r.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/sainsmart18fb.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/hy28afb.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/ads7846_device.ko
/lib/modules/3.6.11+/kernel/drivers/video/fbtft/fb_ili9341.ko

$ dmesg:
[  483.720251] fbtft_device:  SPI devices registered:
[  483.720287] fbtft_device:      spidev spi0.0 500kHz 8 bits mode=0x00
[  483.720302] fbtft_device:      spidev spi0.1 500kHz 8 bits mode=0x00
[  483.720313] fbtft_device:  'fb' Platform devices registered:
[  483.720333] fbtft_device:      bcm2708_fb id=-1 pdata? no
[  483.720378] fbtft_device: Deleting spi0.0
[  483.723141] spi spi0.0: setup: want 250000000 Hz; bus_hz=250000000 / cdiv=2 == 125000000 Hz; mode 0: cs 0x00000000
[  483.723175] spi spi0.0: setup: cd 0: 250000000 Hz, bpw 8, mode 0x0 -> CS=00000000 CDIV=0002
[  483.723303] fbtft_device:  GPIOS used by 'hello15':
[  483.723321] fbtft_device:    'reset' = GPIO25
[  483.723331] fbtft_device:    'dc' = GPIO24
[  483.723339] fbtft_device:    'led' = GPIO23
[  483.723347] fbtft_device:  SPI devices registered:
[  483.723360] fbtft_device:      spidev spi0.1 500kHz 8 bits mode=0x00
[  483.723372] fbtft_device:      fb_hello spi0.0 250000kHz 8 bits mode=0x00
[  483.758327] fb_hello spi0.0: fbtft_request_gpios: 'reset' = GPIO25
[  483.758362] fb_hello spi0.0: fbtft_request_gpios: 'dc' = GPIO24
[  483.758382] fb_hello spi0.0: fbtft_request_gpios: 'led' = GPIO23
[  483.758396] fb_hello spi0.0: fbtft_verify_gpios()
[  483.758410] fb_hello spi0.0: init_display()
[  483.758419] Hello World
[  483.867831] fb_hello spi0.0: Display update: 2743 kB/s (109.353 ms), fps=0 (0.000 ms)
[  483.868796] graphics fb1: fb_hello frame buffer, 320x480, 300 KiB video memory, 4 KiB buffer memory, fps=20, spi0.0 at 250 MHz


karlkiste
Posts: 189
Joined: Tue Jan 22, 2013 8:50 am
Location: berlin, germany

Re: 3.5 TFT hvga module interface

Thu Oct 17, 2013 1:00 pm

I'm not familiar with the general subject, but...
spi0.0 at 250 MHz
That sounds a bit fast to me! I'd start way lower, like 5 or 10 MHz. If all is well, you can rise the data rate, but for debugging slow it down to a safe rate.

notro
Posts: 695
Joined: Tue Oct 16, 2012 6:21 pm
Location: Drammen, Norway

Re: 3.5 TFT hvga module interface

Thu Oct 17, 2013 6:01 pm

Around 40MHz is the fastest I have done, but start low as @karlkiste suggests.

Can you post fb_hello.c?

You can switch console at runtime with con2fbmap 1 1.

You can use the debug argument to get more info in the kernel log: https://github.com/notro/fbtft/wiki/Debug

User avatar
voynich
Posts: 10
Joined: Sun Oct 06, 2013 11:38 pm

Re: 3.5 TFT hvga module interface

Sat Oct 19, 2013 4:40 am

I've lowered the
speed to 10 mhz
fps to 16,
but nothing happens screen still black when using:

Code: Select all

 con2fbmap 1 1
screen stays black with different speed and fps combinations.
I've used the debugging as you said:

Code: Select all

Interfacing:
3v3             3v3
RS              GPIO 24
MOSI           GPIO10
CS               CE0
SCLK           GPIO11
RST             GPIO25
BL                GPIO18
GND            GND

lsmod:
Module                  Size  Used by
fb_hello                1982  1 
fbtft_device           21718  0 
fbtft                  31081  2 fb_hello,fbtft_device
syscopyarea             3136  1 fbtft
sysfillrect             3302  1 fbtft
sysimgblt               2195  1 fbtft
fb_sys_fops             1404  1 fbtft
spidev                  5240  0 
spi_bcm2708             5414  0 
snd_bcm2835            16273  0 
snd_pcm                78130  1 snd_bcm2835
snd_page_alloc          5129  1 snd_pcm
snd_seq                53349  0 
snd_seq_device          6454  1 snd_seq
snd_timer              19946  2 snd_pcm,snd_seq
snd                    58506  5 snd_bcm2835,snd_timer,snd_pcm,snd_seq,snd_seq_device
leds_gpio               2197  0 
led_class               3592  1 leds_gpio

dmesg:
[   61.514339] bcm2708_spi bcm2708_spi.0: SPI Controller at 0x20204000 (irq 80)
[   67.938157] fbtft_device:  SPI devices registered:
[   67.938203] fbtft_device:      spidev spi0.0 500kHz 8 bits mode=0x00
[   67.938219] fbtft_device:      spidev spi0.1 500kHz 8 bits mode=0x00
[   67.938229] fbtft_device:  'fb' Platform devices registered:
[   67.938248] fbtft_device:      bcm2708_fb id=-1 pdata? no
[   67.938292] fbtft_device: Deleting spi0.0
[   67.938702] spi spi0.0: setup: want 10000000 Hz; bus_hz=250000000 / cdiv=25 == 10000000 Hz; mode 0: cs 0x00000000
[   67.938732] spi spi0.0: setup: cd 0: 10000000 Hz, bpw 8, mode 0x0 -> CS=00000000 CDIV=0019
[   67.938858] fbtft_device:  GPIOS used by 'hello15':
[   67.938874] fbtft_device:    'reset' = GPIO25
[   67.938883] fbtft_device:    'dc' = GPIO24
[   67.938892] fbtft_device:    'led' = GPIO18
[   67.938899] fbtft_device:  SPI devices registered:
[   67.938911] fbtft_device:      spidev spi0.1 500kHz 8 bits mode=0x00
[   67.938923] fbtft_device:      fb_hello spi0.0 10000kHz 8 bits mode=0x00
[   67.973988] Hello World
[   68.252098] graphics fb1: fb_hello frame buffer, 320x480, 300 KiB video memory, 4 KiB buffer memory, fps=16, spi0.0 at 10 MHz
[   84.486773] fb_hello spi0.0: fbtft_update_display(start_line=400, end_line=415)
[   84.496069] fb_hello spi0.0: Display update: 1075 kB/s (9.300 ms), fps=0 (0.000 ms)
[   84.686769] fb_hello spi0.0: fbtft_update_display(start_line=400, end_line=415)
[   84.886769] fb_hello spi0.0: fbtft_update_display(start_line=400, end_line=415)
[   85.086769] fb_hello spi0.0: fbtft_update_display(start_line=400, end_line=415)
[   85.286770] fb_hello spi0.0: fbtft_update_display(start_line=400, end_line=415)
[   85.486767] fb_hello spi0.0: fbtft_update_display(start_line=400, end_line=415)
[   85.686771] fb_hello spi0.0: fbtft_update_display(start_line=400, end_line=415)
[   85.886770] fb_hello spi0.0: fbtft_update_display(start_line=400, end_line=415)
[   86.086774] fb_hello spi0.0: fbtft_update_display(start_line=400, end_line=415)
[   86.286776] fb_hello spi0.0: fbtft_update_display(start_line=400, end_line=415)
[   86.486770] fb_hello spi0.0: fbtft_update_display(start_line=400, end_line=415)
[   86.686770] fb_hello spi0.0: fbtft_update_display(start_line=400, end_line=415)
[   86.886768] fb_hello spi0.0: fbtft_update_display(start_line=400, end_line=415)
[   87.086769] fb_hello spi0.0: fbtft_update_display(start_line=400, end_line=415)
[   87.286779] fb_hello spi0.0: fbtft_update_display(start_line=400, end_line=415)
[   87.486771] fb_hello spi0.0: fbtft_update_display(start_line=400, end_line=415)
[   87.686769] fb_hello spi0.0: fbtft_update_display(start_line=400, end_line=415)
[   87.886772] fb_hello spi0.0: fbtft_update_display(start_line=400, end_line=415)
[   88.086767] fb_hello spi0.0: fbtft_update_display(start_line=400, end_line=415)
[   88.286793] fb_hello spi0.0: fbtft_update_display(start_line=400, end_line=415)
I don't change anything in fb_hello.c
I just load spi_bcm2708 before fbtft.
Is there anything(code etc.) to test the screen is not broken?
I'm new to programming just started python.
Can a 8051 microcontroller code be ported to linux(raspberry pi)?
What do i need to do that?

notro
Posts: 695
Joined: Tue Oct 16, 2012 6:21 pm
Location: Drammen, Norway

Re: 3.5 TFT hvga module interface

Sat Oct 19, 2013 7:35 pm

> I don't change anything in fb_hello.c

fb_hello.c is just a skeleton driver that does nothing, except print to the kernel log.

You have to flesh out init_display() and set_addr_win() to match your display controller.
Have a look at how the other drivers do it.

notro
Posts: 695
Joined: Tue Oct 16, 2012 6:21 pm
Location: Drammen, Norway

Re: 3.5 TFT hvga module interface

Sat Oct 19, 2013 7:43 pm

Do you have a link to a product page or something?

User avatar
voynich
Posts: 10
Joined: Sun Oct 06, 2013 11:38 pm

Re: 3.5 TFT hvga module interface

Mon Oct 21, 2013 1:48 am

I buy it from ebay.
I contacted the seller but he refused to name the controller.
i just have a source code for 8051 microcontroller .
I searched online and found two possibilities:
ILI9486L
and
HX8357.
The seller website:
www.tinylcd.com
I bought the 3.5" tft module.

notro
Posts: 695
Joined: Tue Oct 16, 2012 6:21 pm
Location: Drammen, Norway

Re: 3.5 TFT hvga module interface

Mon Oct 21, 2013 6:35 pm

> I contacted the seller but he refused to name the controller.

Not an easy place to start from.
If you post the code somewhere (pastebin.com), I can have a look at it.

User avatar
voynich
Posts: 10
Joined: Sun Oct 06, 2013 11:38 pm

Re: 3.5 TFT hvga module interface

Tue Oct 22, 2013 1:31 am

Source code for 8051 microcontroller.
http://pastebin.com/cPrPijcn

I compared the 8051 source code with ILI9341 source code on your wiki and made these three combinations of initialisation sequence:

Code: Select all

Test1:
sudo modprobe flexfb width=480 height=320 buswidth=8 init=-1,0xB0,0x80,-1,0xC0,0x0A,0x0A,-1,0xC1,0x45,0x07,-1,0xC2,0x33,-1,0xC5,0x00,0x42,0x80,-1,0xB1,0xD0,0x11,-1,0xB4,0x02,-1,0xB6,0x00,0x3B,-1,0xB7,0x07,-1,0x36,0x2B,-1,0xF0,0x36,0xA5,0xD3,-1,0xE5,0x80,0xE5,0x01,0xB3,0x00,0xE5,0x00,-1,0xF0,0x36,0xA5,0x53,-1,0xE0,0x00,0x35,0x33,0x00,0x00,0x00,0x00,0x35,0x33,0x00,0x00,0x00,-1,0x3A,0x55,-1,0x11,-2,250,-1,0x29,-2,20,-3

Test 2:
sudo modprobe flexfb width=480 height=320 buswidth=8 init=-1,0xB0,0x80,-1,0xC0,0x0A,0x0A,-1,0xC1,0x45,0x07,-1,0xC2,0x33,-1,0xC5,0x00,0x42,0x80,-1,0xB1,0xD0,0x11,-1,0xB4,0x02,-1,0xB6,0x00,0x3B,-1,0xB7,0x07,-1,0x36,0x2B,-1,0xF0,0x36,0xA5,0xD3,-1,0xE5,0x80,0xE5,0x01,0xB3,0x00,0xE5,0x00,-1,0xF0,0x36,0xA5,0x53,-1,0x3A,0x55,-1,0x11,-2,250,-1,0x29,-2,20,-3

Test 3:
sudo modprobe flexfb width=480 height=320 buswidth=8 init=-1,0xB0,0x80,-1,0xC0,0x0A,0x0A,-1,0xC1,0x45,0x07,-1,0xC2,0x33,-1,0xC5,0x00,0x42,0x80,-1,0xB1,0xD0,0x11,-1,0xB4,0x02,-1,0xB6,0x00,0x22,0x02,0x3B,-1,0xB7,0x07,-1,0x36,0x09,0x2B,-1,0xF0,0x36,0xA5,0xD3,-1,0xE5,0x80,0xE5,0x01,0xB3,0x00,0xE5,0x00,-1,0xF0,0x36,0xA5,0x53,-1,0xE0,0x00,0x35,0x33,0x00,0x00,0x00,0x00,0x35,0x33,0x00,0x00,0x00,-1,0x3A,0x55,-1,0x11,-2,250,-1,0x29,-2,20,-3
Please see the 8051 source code and tell me which one is correct or all are wrong?
When I load flexfb with all these combination the tft initialised and showed console.
But two problem arises:
1.The tft console text is mirror image of original text.
2.The part of picture which is out of region of tft module is superimposed on part which is inside the tft resolution.

notro
Posts: 695
Joined: Tue Oct 16, 2012 6:21 pm
Location: Drammen, Norway

Re: 3.5 TFT hvga module interface

Tue Oct 22, 2013 6:32 pm

You're well on your way here!

This is my take on the init sequence:

Code: Select all

#ifdef TFT_VERTICAL
#warning TFT_320_480_INITIALISED
#else
#warning TFT_480_320_INITIALISED       
#endif

-1,0xB0,0x80,

-1,0xC0,0x0A,0x0A,

-1,0xC1,0x45,0x07,

-1,0xC2,0x33,

-1,0xC5,0x00,0x42,0x80,

-1,0xB1,0xD0,0x11,

-1,0xB4,0x02,

#ifdef TFT_VERTICAL
-1,0xB6,0x00,0x22,0x3B,
#else
-1,0xB6,0x00,0x02,0x3B,
#endif

-1,0xB7,0x07,

#ifdef TFT_VERTICAL
-1,0x36,0x09,
#else
-1,0x36,0x2B,
#endif

-1,0xF0,0x36,0xA5,0xD3,

-1,0xE5,0x80,

-1,0xE5,0x01,

-1,0xB3,0x00,

-1,0xE5,0x00,

-1,0xF0,0x36,0xA5,0x53,

-1,0xE0,0x00,0x35,0x33,0x00,0x00,0x00,0x00,0x35,0x33,0x00,0x00,0x00,

-1,0x3A,0x55,

-1,0x11,

-2,250,

-1,0x29,

-3
To get 480x320, TFT_VERTICAL is not defined. Which results in:

Code: Select all

sudo modprobe flexfb width=480 height=320 buswidth=8 init=-1,0xB0,0x80,-1,0xC0,0x0A,0x0A,-1,0xC1,0x45,0x07,-1,0xC2,0x33,-1,0xC5,0x00,0x42,0x80,-1,0xB1,0xD0,0x11,-1,0xB4,0x02,-1,0xB6,0x00,0x02,0x3B,-1,0xB7,0x07,-1,0x36,0x2B,-1,0xF0,0x36,0xA5,0xD3,-1,0xE5,0x80,-1,0xE5,0x01,-1,0xB3,0x00,-1,0xE5,0x00,-1,0xF0,0x36,0xA5,0x53,-1,0xE0,0x00,0x35,0x33,0x00,0x00,0x00,0x00,0x35,0x33,0x00,0x00,0x00,-1,0x3A,0x55,-1,0x11,-2,250,-1,0x29,-3

User avatar
voynich
Posts: 10
Joined: Sun Oct 06, 2013 11:38 pm

Re: 3.5 TFT hvga module interface

Wed Oct 23, 2013 3:38 am

WE did it.
The tft initialised and display console with all its grace.
Thank You very much,Sir
I'm going to learn coding right away.
Attachments
23102013042.jpg
23102013042.jpg (53.55 KiB) Viewed 8616 times

notro
Posts: 695
Joined: Tue Oct 16, 2012 6:21 pm
Location: Drammen, Norway

Re: 3.5 TFT hvga module interface

Wed Oct 23, 2013 2:43 pm

Great!

I would like to buy one myself. Do you have a link to an ebay auction?

notro
Posts: 695
Joined: Tue Oct 16, 2012 6:21 pm
Location: Drammen, Norway

Re: 3.5 TFT hvga module interface

Wed Oct 23, 2013 6:28 pm

I found it: http://www.ebay.in/itm/3-5-Inch-TFT-SPI ... 616wt_1139

Sadly on ebay they only ship to India. I also tried to buy on http://www.tinylcd.com/, but there they only ship to India and the US.

rajivdeo
Posts: 3
Joined: Tue Oct 29, 2013 6:10 am

Re: 3.5 TFT hvga module interface

Tue Oct 29, 2013 6:21 am

Thanks for the great timely post!
I have been struggling to connect TinyLCD's 3.5" color LCD with Rpi for last few weeks. This post is a ray of hope.
Can I have clear instructions on how you did get to connecting the LCD with Rpi? Some of my doubts based on what I gathered from this post are -
1. You were able to initialize the display using modprobe alone?
2. You connected the 8 pins of LCD to the GPIO pins as described?
3. Which font you are using? Are you pre-loading it?

Please confirm and explain.
Many thanks in advance.

texy
Forum Moderator
Forum Moderator
Posts: 5160
Joined: Sat Mar 03, 2012 10:59 am
Location: Berkshire, England

Re: 3.5 TFT hvga module interface

Tue Oct 29, 2013 8:01 am

voynich wrote:WE did it.
The tft initialised and display console with all its grace.
Thank You very much,Sir
I'm going to learn coding right away.
Hi,
can you confirm the maximum SPI bus speed you can achieve and also the fps?
Thanks,
Texy
Various male/female 40- and 26-way GPIO header for sale here ( IDEAL FOR YOUR PiZero ):
https://www.raspberrypi.org/forums/viewtopic.php?f=93&t=147682#p971555

User avatar
voynich
Posts: 10
Joined: Sun Oct 06, 2013 11:38 pm

Re: 3.5 TFT hvga module interface

Fri Nov 01, 2013 12:35 am

1. You were able to initialize the display using modprobe alone?
Nope you have to use the notro's kernel.
https://github.com/notro/fbtft/wiki
update your raspbian then use commands on Install section.
2. You connected the 8 pins of LCD to the GPIO pins as described?
Yes exactly same.
3. Which font you are using? Are you pre-loading it?
The fonts are already inbuilt with notro's kernel.
you can enable them by editing /boot/cmdline.txt file.
https://github.com/notro/fbtft/wiki/Boot-console
You can get answers to most of your question at
https://github.com/notro/fbtft/wiki/_pages
Give thanks to notro for his amazing framebuffer driver,without it this can't be done.
Last edited by voynich on Fri Nov 01, 2013 12:44 am, edited 1 time in total.

User avatar
voynich
Posts: 10
Joined: Sun Oct 06, 2013 11:38 pm

Re: 3.5 TFT hvga module interface

Fri Nov 01, 2013 12:42 am

Texy I tried to increase the bus speed and fps but nothing happens.
Although the display works upto 250 Mhz and 33 fps

texy
Forum Moderator
Forum Moderator
Posts: 5160
Joined: Sat Mar 03, 2012 10:59 am
Location: Berkshire, England

Re: 3.5 TFT hvga module interface

Fri Nov 01, 2013 11:01 am

voynich wrote:Texy I tried to increase the bus speed and fps but nothing happens.
Although the display works upto 250 Mhz and 33 fps
Hi,
did you mean the specs are 250mhz and 33fps, or that is what fbtft reports?
...thats quite critical ;)

Texy
Various male/female 40- and 26-way GPIO header for sale here ( IDEAL FOR YOUR PiZero ):
https://www.raspberrypi.org/forums/viewtopic.php?f=93&t=147682#p971555

Return to “Interfacing (DSI, CSI, I2C, etc.)”