bnahill / f4discovery-daughter Goto Github PK

SPI transactions

Get the LCD touch screen working.

Just about 10-15 mils should do it. The clearance is just very minimal now. At the very least it would be nice to be able to get a small wire through there from the prototyping area.

Verify connections to be correct for 6800-style interface

ALL interrupt lines
LCD control lines
SPI2 if possible including DOUT from microphone - SPI1 if SPI2 not available completely
Power status signals and enable

Some resources suggest powering the LCD backlight with 3.3V. Since we have 3V, this should be verified and the current draw should be tested. to see if it can be driven by a GPIO. If it can't we can use an cheap LED driver IC to be able to use PWM to vary brightness.

Be sure to pull enable down

It's not evident enough what the configuration of the jumpers is. It should be made more clear with silkscreen values.

Pin 16

They don't really stick out much. I think they should stick out more.

Let's make list of missing parts:

• L1: 7n5 0402
• L7: 3n9 0402
• L8: 4n7 0402
• FB1: 0805 ferrite bead
• J6: The correct USB connector -- 10118194-0001LF
• C40/41: 4n7 (5%) 0402
• C38/39: 2n4 (5%) 0402
• R28-31: 2k8 (1%) 0402

I think two LED colors would be good instead of both blue. Red or green would both be nice. More can be said with two colors...

Anything else?

It just looks weird now...

Move pin rows 0.1" closer

The output of the TLV61220 regulator is non-zero even when EN_NXT_4.3V is set to 0. A MOSFET configuration similar to backlight control should be implemented.

The alignment isn't quite right and there isn't room for error. I can get two screws in fine but it ends up a little off-axis.

I know some members of this project might not agree, but there are many resistors and capacitors that have been given 402-sized footprints where the abundance of space available on the board does not justify this. Sizes should be changed back to 603 or 805 where appropriate.

because the option of Wi-Fi is just awesome.