Introducing the ARM PRO MINI board - ARM Made Easy

[dansku]

Thanks Zapta for fixing my noob soldering mistakes!!



I'm just having few problems with the board that maybe you guys could help me.

I uploaded all examples with no problem, slow blink, fast blink, then I also compiled some code in the MBED IDE.
But after I built a code with only 10ms of delay between blinks (the delay shouldn't be a problem), now I can't get the board back to USB Mode. Also when I plug the board the green (USB) led doesn't turn on anymore.

Could it be a usb soldering problem?



Thanks

[zapta]

Is it possible that it's just an hardware problem?  Some short, broken connection, etc?

Can you send me that bad binary, I will try to reproduce it here.   

[dansku]

Is it possible that it's just an hardware problem?  Some short, broken connection, etc?

Can you send me that bad binary, I will try to reproduce it here.

This is the file that I uploaded:
http://cl.ly/2p0m0P1a381B

Maybe I broken connection on the usb plug?

Let me know if yours worked fine!
Thanks!

[zapta]

Is it possible that it's just an hardware problem?  Some short, broken connection, etc?

Can you send me that bad binary, I will try to reproduce it here.

This is the file that I uploaded:
http://cl.ly/2p0m0P1a381B

Maybe I broken connection on the usb plug?

Let me know if yours worked fine!
Thanks!

Hi dansku, your mbed file seems to run just fine, except that it generates blinking at 50hz (too fast).  Also, I don't have a problem going back to ISP mode.

You can observe the blinking with an osciloscope or a voltmeter (half voltage on the LED output). If you can't get into ISP mode it's probably some short or connection issue. I have a chopped micro USB cable that I use to test the USB connectivity (just chop the computer side connector and expose the wires).

I am getting more boards next week. Will be able to send you one for comparison if it will help.

[dansku]

Is it possible that it's just an hardware problem?  Some short, broken connection, etc?

Can you send me that bad binary, I will try to reproduce it here.

This is the file that I uploaded:
http://cl.ly/2p0m0P1a381B

Maybe I broken connection on the usb plug?

Let me know if yours worked fine!
Thanks!

Hi dansku, your mbed file seems to run just fine, except that it generates blinking at 50hz (too fast).  Also, I don't have a problem going back to ISP mode.

You can observe the blinking with an osciloscope or a voltmeter (half voltage on the LED output). If you can't get into ISP mode it's probably some short or connection issue. I have a chopped micro USB cable that I use to test the USB connectivity (just chop the computer side connector and expose the wires).

I am getting more boards next week. Will be able to send you one for comparison if it will help.

Yes, It may be some problem with the USB connector. I would love the board to make more tests and projects!

I will do some more testing later, I let you know how it goes! Thanks for the help! 

[zapta]

I would love the board to make more tests and projects!

I am playing now with a 1.3" SPI OLED display attached to the ARM PRO MINI. The u8g graphics library is easy to use, it's fun to see the things moving on the screen, and everything including the USB serial stack, graphics library and printf library takes ~10k so plenty of room for application code.  Life is good.

[LabSpokane]

I would love the board to make more tests and projects!

I am playing now with a 1.3" SPI OLED display attached to the ARM PRO MINI. The u8g graphics library is easy to use, it's fun to see the things moving on the screen, and everything including the USB serial stack, graphics library and printf library takes ~10k so plenty of room for application code.  Life is good.

Got a good source to share for the OLED?

[zapta]

Got a good source to share for the OLED?

The original source is Heltec in china  http://heltec.diytrade.com/sdp/2044581/4/pl-6785993/0/Product_Catalog.html .  For single units ebay is probably your best choice. The only problem is that they have several variations with no clear model numbers.

The ones I am using are
* 1.3", 128 x 64.
* SPI  (faster than I2C)
* Heltec 'old style'  (they have the pins,  GND, VCC, SCL, SDA, RST, D/C, CS is permanently selected, and they don't have onboard 3.3V LDO)
* white (they have a SSD1306 controller, the blue ones have SH1106).

This one on ebay looks like the ones I am using:

http://www.ebay.com/itm/1-3-SPI-Serial-128X64-OLED-LCD-LED-Display-Module-3-5v-White-for-Arduino-/261402217702?pt=LH_DefaultDomain_0&hash=item3cdcc94ce6



I had in the past ebay sellers advertising it and shipping a different one (same value, they don't understand the difference). I think that as long as you get a 1.3" SPI with SSD1306 (preferred) or SH1106 (requires minor patch in u8glib) you should be fine with some tweaking. The u8glib maintainer is very responsive.

If you want a consistent source of such displays, talk directly to Heltec. They are responsive and will ship also small quantities.

[Jaros]

If you want a consistent source of such displays, talk directly to Heltec. They are responsive and will ship also small quantities.

May I ask owners of this display, what is the real mA consumption. Does it depend on how many "tiny LEDs" is on?
Is it possible to take a picture in direct sun, to see how good visibility is of these displays in daylight.

I purchased Sharp MemoryLCD to play with, but they are "expensive"  and not sure yet if I want to go with this in my project.

and big Thank You to Zapta for sending me one of his arminis.
Regards
Jarek

[dansku]

Is it possible that it's just an hardware problem?  Some short, broken connection, etc?

Can you send me that bad binary, I will try to reproduce it here.

This is the file that I uploaded:
http://cl.ly/2p0m0P1a381B

Maybe I broken connection on the usb plug?

Let me know if yours worked fine!
Thanks!

Hi dansku, your mbed file seems to run just fine, except that it generates blinking at 50hz (too fast).  Also, I don't have a problem going back to ISP mode.

You can observe the blinking with an osciloscope or a voltmeter (half voltage on the LED output). If you can't get into ISP mode it's probably some short or connection issue. I have a chopped micro USB cable that I use to test the USB connectivity (just chop the computer side connector and expose the wires).

I am getting more boards next week. Will be able to send you one for comparison if it will help.

Yes, It may be some problem with the USB connector. I would love the board to make more tests and projects!

I will do some more testing later, I let you know how it goes! Thanks for the help! 

I made a bunch of tests on the board, checked connections, short-circuits. Everything seems to be working fine.

The green LED is connected to PIN 02, which is the IO from the µC and apparently is not turning "HIGH", or "LOW". I guess it should be turning LOW because the cathode of the LED is connected.

The problem could be with the µC maybe?

I will later on destroy a USB cable and see if it could be a problem with the connector!

[zapta]

I would try this

1. (I presume that blinking mbed program is still running on your board). Reset the board and observe the voltage at the red led output pio0_7. If it has 50 hz square wave the program is running and the clock and the MCU are alive. (if you don't have an osciloscope, measure the dc voltage, it should be half of 3.3v).

2. Measure the voltage on the MCU PIO0_1 and see that the voltage changes between 0 and 3.3v when you press on the ISP button. This is required to enable the ISP mode.

3. Verify that PIO0_3 input of the MCU has 3.3V. This is required to enable the USB ISP mode.

4. Use a chopped USB cable to test the usb data path from the cable to the MCU (via the 33Ohm resistors). Make sure there are no shorts.

The connector on your board felt notchy when I inserted the cable. I assumed it got extra flux or solder paste, but it did work.

Let see if this will help.


If anybody is interested, schematic here.
https://github.com/zapta/arm/blob/master/pro-mini/eagle/arm-pro-mini-schematic.pdf?raw=true

[dansku]

1 - pio_07 -> TP3  = 1.6V => OK

2 - pio_01 -> TIP17 => 3.3V, doesn't change when pressed the ISP Button

3 - pio_03 -> TIP25 =~ 4.8V, that doesn't sound good!!

Somehow something got shorted and the µC ist kaput. But it's funny that the it's working and blinking. (why didn't I used such a fast speed)

[zapta]

2. Pressing the ISP button need to short this to ground so check connectivity. (Verify the pin number in the schema, maybe I gave you the wrong pin number.

3. Ideally it should have a voltage divider, currently it has a current limiting resistor. Will revisit it. Also will let you know my reading later at home.

#2 above seems to be the problem.

[dansku]

Perfect!! The problem was with that button!! I kinda broke it, but anyway, by shorting that button it entered in USB mode and now it's working. Just need to solder a new one!!

Perfect, thank you very much for the help!!

Working like a charm now!!


I know it's dirty and ugly, but works and will stay like this until I order new parts  O0

[zapta]

Awesome!

The board you sent me arrived with the two buttons dead, no tactile feel, probably from the post office sorting machine, so I replaced them. Maybe there is  also a damaged trace in that area.

Have fun.

[zapta]

[May I ask owners of this display, what is the real mA consumption. Does it depend on how many "tiny LEDs" is on?
Is it possible to take a picture in direct sun, to see how good visibility is of these displays in daylight.

I purchased Sharp MemoryLCD to play with, but they are "expensive"  and not sure yet if I want to go with this in my project.

Mine takes 23ma to 45ma depending on the number of pixels turned on.

It's very visible indoor, even with direct light, will try to test it this weekend outdoor in the sun (it's winter here though). For outdoor application a reflective display may be a better choice.

[Jaros]

[May I ask owners of this display, what is the real mA consumption. Does it depend on how many "tiny LEDs" is on?
Is it possible to take a picture in direct sun, to see how good visibility is of these displays in daylight.

I purchased Sharp MemoryLCD to play with, but they are "expensive"  and not sure yet if I want to go with this in my project.

Mine takes 23ma to 45ma depending on the number of pixels turned on.

It's very visible indoor, even with direct light, will try to test it this weekend outdoor in the sun (it's winter here though). For outdoor application a reflective display may be a better choice.

appreciate Your time on this. It is too much, for solar panel/battery supported design.

and about

no tactile feel, probably from the post office sorting machine

I purchased one time 1000pieces very cheap tactile switches form China seller. It said ROHS compliant, but first batch under reflow oven melted in half. Some of them still had a tactile switch look, but there was no tactile feel at all.
I had to buy again, twice more expensive.
Regards
Jarek

[zapta]

I purchased one time 1000pieces very cheap tactile switches form China seller. It said ROHS compliant, but first batch under reflow oven melted in half. Some of them still had a tactile switch look, but there was no tactile feel at all.
I had to buy again, twice more expensive.
Regards
Jarek

I am using these ones myself http://www.digikey.com/short/7mvrq9 . Probably can cut cost by replacing USB connector, switches, crystal, etc. Can also remove some components such as the diodes (running USB only), the USB protection diodes (it works without them, no problem so far), the LEDs, etc. Not sure how much the MCU cost itself can go down LPC11U35FHI33/501   

I am building in small quantities so didn't investment too much in cost reduction but there are a few low hanging fruits.

[dansku]

Just made a super short "Hello World" tutorial for the Arm Pro Mini...
Hope it helps anyone

[zapta]

Just made a super short "Hello World" tutorial for the Arm Pro Mini...
Hope it helps anyone

Great!   Looks very easy ;-)

[dansku]

Just received a PCB that I made based on the Arm Pro Mini, I called it Ares I.

I am still using the Reset/ISP switches. It is almost the same design. I removed the Led on Pin0_7, added all the pin numbers and kept the debugging, though I am planning on removing in on future releases.

It was a fun design, I learned a lot creating the board and understanding the ArmProMini design, thank you Zapta for all the tips and useful information!!

[zapta]

Looks very nice. I like the clear pin numbers marking.

[zapta]

The ARM PRO MINI now has a little friend, the ARM PRO TINY. It's a bare bone version of ARM PRO MINI that is still software compatible and has the virtual disk USB/ISP.

Diagram
https://github.com/zapta/arm/blob/master/pro-tiny/eagle/arm-pro-tiny-schematic.pdf?raw=true

[nctnico]

I looked at the schematics. I wish you put multiple processor pins on one PCB pin so you can use more peripherals.

[zapta]

I looked at the schematics. I wish you put multiple processor pins on one PCB pin so you can use more peripherals.

That's a very interesting idea.