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Topic: Bus Pirate "Ultra" v1a & v1b with ICE40 and Icestorm :) (Read 7934 times) previous topic - next topic

Re: Bus Pirate "Ultra" v1a & v1b with ICE40 and Icestorm :)

Reply #75
Hey Mike,

That's a nice display. Anything over 320*240 generally needs a 8 or 16 bit parallel interface (we use SPI). I imagine in v2 eventually we end up with a second stm32 as a graphics driver or a big mcu with MIPI.
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Re: Bus Pirate "Ultra" v1a & v1b with ICE40 and Icestorm :)

Reply #76
seems to imply its SPI also, inteface says IIC, whic in chinglese means SPI

the    ILI9806E seems to support SPI

whats the model of the 2.8" one you are looking at ?

Mike

Re: Bus Pirate "Ultra" v1a & v1b with ICE40 and Icestorm :)

Reply #77
Currently I'm using KD028QVFMA017, for capacitive touch we're using KD028QVFMA017-C002A.

Startek's website is down, but when it comes back up the 4.3" datasheet is here and I'll have a look.

In general driving all those 16bit pixels from SPI seems slow. We have room for improvement using DMA to transfer the background images from the flash chip to the display, but i have this nagging feeling that we'll need to use an 8 or 16bit parallel interface  when we get to a future v2 or v3.
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Re: Bus Pirate "Ultra" v1a & v1b with ICE40 and Icestorm :)

Reply #78
Most displays can be updated partially, which makes the impact smaller. The only things changing (frequently) are the voltages which occupies only small areas.

general workflow for the v1 I suggest:

display off, send the big gfx using DMA, display off and partially update the voltages during use.

Re: Bus Pirate "Ultra" v1a & v1b with ICE40 and Icestorm :)

Reply #79
X

For the bigger display - SPI interface pins are listed in the pin description, but there are no IM0...3 pins to select the mode (maybe this chip works differently). The schematic also doesn't mention an SPI mode. I have not looked at the ILI9806E datasheet, maybe the mode is selected differently than the smaller version.
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Re: Bus Pirate "Ultra" v1a & v1b with ICE40 and Icestorm :)

Reply #80
The data sheet says

a-Si TFT LCD Single Chip Driver   480(RGB)x864 Resolution and 16.7M-color The ILI9806E is a 16.7M single-chip SOC driver for a-Si TFT liquid crystal display panels with a resolution up to 480(RGB)x864. The ILI9806E is comprised of a 1441-channel source driver, an gate-IC-less level shifter, and a power supply circuit.   The  ILI9806E  supports  3-line  serial  peripheral  interface  to  input  commands.  The  ILI9806E  supports  a  RGB  (16-/18-/24-bit) data bus for video image display. For high-speed serial interface, the MIPI DSI interface mode, the  ILI9806E  supports  two  data  lanes  and  one  clock  lane  for  high-speed  and  low  power  transmission  in  both  directions with low EMI .

no idea what a MIPI DSI interface is, but an FPGA should eat it !!!

seems to imply a 10 pin interface see datasheet page 20.

needs  SPI to set register IM[3:0] to 0111  or 1111, then its activated, with data on HS_D0P,HS_D0N, HS_D1P, HS_D1N, HS_CP, HS_CN, SDI,SDO,SCL(rising or falling edge) ,CSX

 

Re: Bus Pirate "Ultra" v1a & v1b with ICE40 and Icestorm :)

Reply #81
Interesting. Commands through spi and pixel data parallel. MIPI is the way to go. V2 will use an arm with MIPI support.
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Re: Bus Pirate "Ultra" v1a & v1b with ICE40 and Icestorm :)

Reply #82

check out  DV042FBM-T81

4.17inch ADS TFT LCD with cap touch
DV042FBM-T81 is a colour active matrix TFT-LCD Panel using amorphous silicon TFT's This TFT-LCD has a 4.17 inch measured active area.

Ideal for home and building automation - fits in a standard light switch.

Resolution 540 x 540 pixels
MIPI Interface
Viewing angle 85deg x 85deg

DV042FBM-T81



Re: Bus Pirate "Ultra" v1a & v1b with ICE40 and Icestorm :)

Reply #83
Ian,

its 4 months since the last update,

any update ?

Mike