unexpected response from display:-0

[xueyanqin]

Hello.
When loading PmmC,it displays"unexpected response from display:-0".
How to solve it?
The download cable is ok,because it works well for old PICASO.
The crystal oscillator works well and the woking voltage of PICASO is good.
Where is the problem?
Thank you.

[xueyanqin]

1、The light of COM is always red.
2、The connections of progromming pins are right.
3、Crystal oscillator works well.
4、The power of PICASO are supported.
5、The programming cable is good.
Whether the PICASO that is bought from agent is not certified products?

[ESPsupport]

Can you show us some photos of the display and programming cable connected up?

Are you using just a Picaso chip? (i.e. you have made your own 'display'?

What options have you used to load the PmmC?

[xueyanqin]

Hello.
The photo:

[xueyanqin]

Thank you for your reply.

[James_4DSystems]

Hello

Very interesting board there - is this something you designed yourself, or is this from another company?

The programming signals are made up of RX0 and TX0. On the board you are using, is RX0 and TX0 dedicated only to programming the display, or is the connection also used to talk to other IC's on the board?

You have provided only the schematic of the Picaso portion, however that does not give me a full indication of how it is connected up.

If RX0 and TX0 are connected to other things, then you are going to have a hard time programming Picaso without disconnecting them.

What is this display module used for exactly? It has a lot of other components on it. It looks very interesting.

If you can provide more information, even if you wish to email them to me directly, james at 4dsystems dot com dot au
I am happy to help further.

Looking at the programming header in the schematic, it has no 5V connected to the header. So I assume you are powering the display module up separately, and then programming it with the programmer you have?

Regards

[xueyanqin]

Thank you,James.
1、The board is designed by others and I am responsible for producting and upgrading.I have producted once and they work well.This time I prepare to make some boards,then the problem appears.
2、RX0 and TX0 are not connected to other things,which are only used for programming.
3、The device is used for measuring ECG and Blood oxygen.The main MCU is STM32F405.
4、There is 5V which is connected to the programming header.LCD_POWER_1.This power is good.
I will email my schematic diagram to you.
Thank you for your help.

[xueyanqin]

Hello,James.
1、
2、I always manually program the PmmC,the screenshot is as follow.
3、I have made five units which are working well.The former designer have made many sets of this device and they are working well.The programming header is always used as I show you.
4、The programming cable I use is the board which is made of CP2102.It is always working well.

[James_4DSystems]

Hello again.

OK, everything sounds like you have it under control then. So you have made 5 units which all worked well.
So the last working units were made from the former designer?
Now you have made some more units (or just this 1 more?), and these ones are no longer working?

What freq crystal have you used?
Are you using identical 100% same components as the last designer, or have you changed something?

[xueyanqin]

Hello.
I made 5 units this time,which is changed a little from the former 5 units.but the changes have no connection with the display unit.
2 in 5 units I use are not programmed .
The crystal is 12M.
The components of my new board are bought again.Maybe some are not good,but I don't know which are they.
Thank you.

[James_4DSystems]

OK I understand.
So at least you have 3 units which are working then, so you know your design is OK.

If Picaso is not programmming, it could be the crystal or the caps on the crystal. You did however say the crystal is OK, along with the power to the Picaso.
please check you have good connections between your programming header and the TX, RX, RESET pins to Picaso. Maybe one of the resistors is faulty or dry solder joint.
The other thing could be a solder bridge or short under Picaso.
Can you please send a picture of the footprint you have applied on your PCB for the Picaso?

Regards

[xueyanqin]

Hello.
Sorry ,I can't express clearly.The another 3 units have not been tried and I have no idear if they are good.
I should check my boards carefully as you told me.
Thank you.

[xueyanqin]

Hello,James.
I soldered the PICASO chip again,changed the crystal of another brand,then it can be loaded PmmC and program.
I don't know why the former crystal is wrong.It indeedly has oscillation waveform whose amplitude is a little smaller than the waveform amplitude of normal board.
Now it is good .


Thank you for your above replys,James and Mark.
Best wishes.

[James_4DSystems]

Very good, I am very happy to hear you got it working.

Please do stay in touch, you have my email - I would love to hear how you progress with your product.

Regards

[xueyanqin]

Ok,James,Thank you.
All the best!