Can't program Sparkfun Red Board with LTE CAT-M Shield Connected

Development Boards Arduino
1

Hi Support,

I recently purchased the Sparkfun Redboard, LTE CAT-m Shield, and Ethernet Sheild. I would like to connect all 3 boards together. However, I the Redboard and the LTE CAT-m Shield seems not to be compatible. When connected via the pin headers (Readboard to LTE Shield) I get the following arduino errors when uploading the sketch:

nary sketch size: 1,052 bytes (of a 32,256 byte maximum)

avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0x30

avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0x20

avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0x30

avrdude: stk500_getsync() attempt 4 of 10: not in sync: resp=0x20

avrdude: stk500_getsync() attempt 5 of 10: not in sync: resp=0x30

avrdude: stk500_getsync() attempt 6 of 10: not in sync: resp=0x20

avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0x30

avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0x20

avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0x30

avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0x20

I do not have these errors with just the Redboard connected, or with the Ethernet shield.

I have tested the pin header for shorts with a continuity meter and found no shorts.

Is the LTE Shield not compatible with the Redboard?

Best Regards,

Mike

2

Is the serial switch set to SOFT on the LTE CAT ?

3

Changing from Hard to soft did not correct this problem:

Binary sketch size: 1,052 bytes (of a 32,256 byte maximum)

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0x00

avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0x30

avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0x20

avrdude: stk500_getsync() attempt 4 of 10: not in sync: resp=0x30

avrdude: stk500_getsync() attempt 5 of 10: not in sync: resp=0x20

avrdude: stk500_getsync() attempt 6 of 10: not in sync: resp=0x30

avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0x20

avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0x30

avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0x20

avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0x30

4

Hello RoboMike5777_2,

Can you try programming the RedBoard without the shield, unplug from computer/power source, mount shields, then repower your unit? This will help to see if the RedBoard is solely having issues.

Also: common things to check would be the serial port, target board, programmer profile, and the USB cable itself. Sometimes the cable might not make a great connection for the data lines.

5

Did you read above??? Of course, I can program it without the shield. Read above everything I did. It’s the Sheild CATM doesn’t work with the redboard.

6

My apologies, I must have missed that line. I can confirm that during upload these boards aren’t having trouble on my end.

Are you uploading custom code or example sketches from our LTE library?

7

I am uploading the example called Blinky

8

Which library is this sketch from?

Are you referring to the basic Arduino Blink sketch? I’m only asking because there are other libraries and examples with the name Blinky.

9

yes it’s the basic Arduino Blink Sketch. As mentioned before, the programmer works fine without the CATM Shield. Then the programmer times out with the Shield. Hence, it is not a code issue, it’s some electrical interference caused by the CATM shield on the programmer. Have you connected the CATM shield to the Redboard to verify this issue?

10

I have connected them. I ran a blank sketch, blink, and example 00_Register_Operator from our LTE library. All three uploaded without errors. Can you provide pictures of your setup?

11

https://www.dropbox.com/s/3a1yg3sdx749g … 8.jpg?dl=0

Here is my image

12

I still think the issue is related to the UART sw

itch, loading the TX/RX on the Arduino. Can you try to switch it again back and forth and make sure it is well shifted to he SOFT side ?

13

I have tried this multiple times per your request and it doesn’t fix the problem.

14

Maybe… let’s try something different. remove the shield and try to insert it again, but bend TX and RX pins a little so they do not make contact when you re-insert.

15

This does resolve this issue.

16

The RX/TX pins go directly to the UART switch. Can you check the switch with an OHM meter. The TX and RX should measure high ( mega ohm or more) when measuring against GND when the switch in SOFT.

17

However, the TX and RX pins are needed to communicate to the Red Board from the Shield , so how do we this to work?

18

Not really. the communication CAN happen with the TX/TX pin 0 an 1 (HARD UART) or with softserial over pin 8 and 9 ( UART SOFT). This softserial approach is the easiest and default. BUT

  1. your switch must switch correctly (and I have still concerns there)

  2. I started working recently with the LTE CAT-M and in the first sketch it tries to communicate with the board on 9600. That did not work as my board worked on 115200. 115K is a very high speed for softserial to work stable. I connected the board to a Mega, serial1, and I am figuring out whether the speed can be set to 9600.

19

The TX/RX pins don’t allow me to program the Red Board, so as stated above by sparkfun tech support - they are disconnected.

20

I am confused, can please confirm:

  1. If you connect the TX/RX pins of the LTE shield to the board you can NOT upload ?

  2. if you do NOT connect the TX/RX pins of the LTE shield to the board you can upload ?

  3. if 2 is correct, where you able to check with an ohm meter the connection/resistance as indicated before ?

Actually you do not need TX /PX pin 0 and 1. SoftSerial can do it …