RAK2245 96 Board with pi zero

pacmenDE · July 24, 2019, 5:24am

Hi hobo,
i used the user manual for 96 board.
https://downloads.rakwireless.com/en/LoRa/RAK2245-96Boards/Hardware-Specification/RAK2245-96Boards_User_Manual_V1.2.pdf to connect the raspi zero.

what i´ve checked and modified is:
:/opt/ttn-gateway/packet_forwarder/lora_pkt_fwd set_eui.sh
GATEWAY_EUI_NIC=“wlan0”
So i get the right GWEUI in local_conf.json

The SX1301 reset pin is on GPIO17 (phys. raspi PIN No 11)
SPI is enabled:
pi@rak-gateway:/opt/ttn-gateway/packet_forwarder/lora_pkt_fwd $ ls -l /dev/spi*
crw-rw---- 1 root spi 153, 0 Jul 24 05:36 /dev/spidev0.0
crw-rw---- 1 root spi 153, 1 Jul 24 05:36 /dev/spidev0.1

and i tested with spitest
pi@rak-gateway:~ $ ./spidev_test -D /dev/spidev0.1
spi mode: 0x0
bits per word: 8
max speed: 500000 Hz (500 KHz)
pi@rak-gateway:~ $ ./spidev_test -D /dev/spidev0.0
spi mode: 0x0
bits per word: 8
max speed: 500000 Hz (500 KHz)

But the packet forwarder will not start…

to start i used the start script under /opt/ttn-gateway/packet_forwarder/lora_pkt_fwd $ sudo ./start.sh

INFO: Little endian host
INFO: found global configuration file global_conf.json, parsing it
INFO: global_conf.json does contain a JSON object named SX1301_conf, parsing SX1301 parameters
INFO: lorawan_public 1, clksrc 1
INFO: no configuration for LBT
INFO: antenna_gain 0 dBi
INFO: Configuring TX LUT with 16 indexes
INFO: radio 0 enabled (type SX1257), center frequency 867500000, RSSI offset -166.000000, tx enabled 1, tx_notch_freq 0
INFO: radio 1 enabled (type SX1257), center frequency 868500000, RSSI offset -166.000000, tx enabled 0, tx_notch_freq 0
INFO: Lora multi-SF channel 0> radio 1, IF -400000 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora multi-SF channel 1> radio 1, IF -200000 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora multi-SF channel 2> radio 1, IF 0 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora multi-SF channel 3> radio 0, IF -400000 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora multi-SF channel 4> radio 0, IF -200000 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora multi-SF channel 5> radio 0, IF 0 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora multi-SF channel 6> radio 0, IF 200000 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora multi-SF channel 7> radio 0, IF 400000 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora std channel> radio 1, IF -200000 Hz, 250000 Hz bw, SF 7
INFO: FSK channel> radio 1, IF 300000 Hz, 125000 Hz bw, 50000 bps datarate
INFO: global_conf.json does contain a JSON object named gateway_conf, parsing gateway parameters
INFO: gateway MAC address is configured to XXXXXXXXXXXXXXXXXX
INFO: server hostname or IP address is configured to “router.eu.thethings.network”
INFO: upstream port is configured to “1700”
INFO: downstream port is configured to “1700”
INFO: downstream keep-alive interval is configured to 10 seconds
INFO: statistics display interval is configured to 30 seconds
INFO: upstream PUSH_DATA time-out is configured to 100 ms
INFO: packets received with a valid CRC will be forwarded
INFO: packets received with a CRC error will NOT be forwarded
INFO: packets received with no CRC will NOT be forwarded
INFO: GPS serial port path is configured to “/dev/ttyAMA0”
INFO: Reference latitude is configured to 10.000000 deg
INFO: Reference longitude is configured to 20.000000 deg
INFO: Reference altitude is configured to -1 meters
INFO: fake GPS is disabled
INFO: Auto-quit after 6 non-acknowledged PULL_DATA
INFO: found local configuration file local_conf.json, parsing it
INFO: redefined parameters will overwrite global parameters
INFO: local_conf.json does not contain a JSON object named SX1301_conf
INFO: local_conf.json does contain a JSON object named gateway_conf, parsing gateway parameters
INFO: gateway MAC address is configured to XXXXXXXXXXXXXX
INFO: packets received with a valid CRC will be forwarded
INFO: packets received with a CRC error will NOT be forwarded
INFO: packets received with no CRC will NOT be forwarded
INFO: [main] TTY port /dev/ttyAMA0 open for GPS synchronization
ERROR: [main] failed to start the concentrator

What else can be the reason?
Regards,
Patrik

Tony_Smith · July 24, 2019, 2:19pm

Some things to check
Have you connected the Radio Reset which is normally connected to GPIO 17 (header pin 11) on the Pi. You can check for the required GPIO pin by inspecting the code in start.sh
This should connect to Pin6 on the 96 connector

Have you connected Pin 35 on the 96 connector to 3.3Volt? This pin sets the inputs of the RAK2245 to work correctly in either a 1.8volt system or a 3.3volt system.

You also need to reduce the SPI clock speed to 2MHz to work with the RAK2245. This should have been taken care of in the code from RAK provided you use the RAK2245 code and not try and use some older code for the 831.

pacmenDE · July 25, 2019, 6:14am

Hi Tony,
thanks for your ideas,
Point 1 Reset PIN is mapped with GPIO 17 and i changed the code in start.sh.

I have connected 96 board pin 37 (5V) with the raspi.5 Volt pin. You mean, that the 96 board is produced to un with 3,3 or 1,8 Volt correctly?

Reduce the SPI spped: BCM2835 driver supports these speeds settings

Is the Raspi not capable with 96 board?
Which file i have to touch to change the spi speed?

Thanks in advance.
Patrik

Tony_Smith · July 25, 2019, 10:10am

First, I have a working gateway using a RAK2245 with a PiZero, So yes, it works with a PiZero or any other Pi for that matter.

I use the Stamp version of the RAK2245 and there is little difference with the 96 Board version. Simply the Stamp unit does not have the 96Board socket fitted. With the 96Board version, you have the option to connect via the 96Board connector OR via the Solder pads on the side of the PCB. Since I have no socket, I connect via the solder pads on the side of the PCB. If I wanted I could solder wires into the holes used by the 96 Board socket.

You need to connect the 96Board pin 37 to 3.3Volts, which is Header Pin 1 on the RasPi. I have no idea of the switching voltage when pin 37 is connected to 5 volts, it may or may not work correctly with a Pi. However I know it works with Pin37 connected to 3.3volt.

For your information
– the Raspi GPIO works on 3.3 volts, which requires Pin37 connected to 3.3 volts
– the 96Board system work on 1.8 volts which requires Pin37 connected to 1.8 volts.

When I changed the SPI speed I edited one of the source code programs and recompiled the Semtech packet forwarder code. This was early this year when the RAK2245 was first released but since then this has been provided by RAK and incorporated in the RAK2245 packet forwarder. My point was don’t try and use the standard Packet Forwarder provided by The Things Network or LoraServer.io as they normally set SPI speed at 8MHz.

Hope this is enough to get it working

pacmenDE · July 25, 2019, 11:41am

Yeah it´s working now …thanks Tony.

External 5 Volt power to PIN 37 and the IOREF pin from 96 board to 3.3 Raspi pin.

Thank you…!!!

Now i have one of the smallest lora gateway ever!!

Patrik

Tony_Smith · July 25, 2019, 11:46am

How small have you achieved?

pacmenDE · July 25, 2019, 11:53am

case would be 10 cm x 10 cm x 6 cm ip66 box…

Tony_Smith · July 25, 2019, 12:00pm

Nice. I’ve gone for a tube, 5cm OD x 50cm long, includes Gateway, antenna, POE power supply and ethernet circuits. Currently building 20 units.

pacmenDE · July 25, 2019, 12:10pm

Now i have to check LinkIt MT7688 as SoC it´s running with opwenwrt and SD Card is not requiered…

pacmenDE · July 25, 2019, 12:10pm

nice format!!
You sell the devices?

Tony_Smith · July 25, 2019, 12:20pm

Will sell in the near future.

BTW, I agree with other SoCs like the MT7688. I’ve tested a few, some have problems with the SPI port, others have limited supply. As a result, I still haven’t settled on a preferred SoC.

pacmenDE · July 25, 2019, 12:27pm

Yes i know. the SPI issue. but it seams there is a spi patch for thi issue. After patching the kernel SPI runs on half duplex mode and the problem is resolved.

Tony_Smith · July 25, 2019, 8:44pm

I’d be interested to hear how you get on with the MT7688 or any other SoC with the SPI in Half Duplex mode. I thought the Semtech SX1301 radio chip required full duplex but I’m keen to learn from your experience.

cstratton · September 22, 2019, 5:51pm

The RAK repos show a solution for this, for example the following patch:

github.com

RAKWireless/RAK831-LoRaGateway-OpenWRT-MT7628/blob/master/products/wisLora/package/utils/lora-gateway/patches/000-lora_gatewap-5.0.1-7688_20170731.patch

--- a/libloragw/src/loragw_spi.native.c	2017-07-31 14:44:45.000000000 +0800
+++ b/libloragw/src/loragw_spi.native.c	2017-07-31 15:02:11.310349162 +0800
@@ -54,8 +54,8 @@
 #define READ_ACCESS     0x00
 #define WRITE_ACCESS    0x80
 #define SPI_SPEED       8000000
-#define SPI_DEV_PATH    "/dev/spidev0.0"
-//#define SPI_DEV_PATH    "/dev/spidev32766.0"
+//#define SPI_DEV_PATH    "/dev/spidev0.0"
+#define SPI_DEV_PATH    "/dev/spidev32766.1"
 
 /* -------------------------------------------------------------------------- */
 /* --- PUBLIC FUNCTIONS DEFINITION ------------------------------------------ */
@@ -173,7 +173,7 @@
     if ((address & 0x80) != 0) {
         DEBUG_MSG("WARNING: SPI address > 127\n");
     }
-
+	//spi_mux_mode = LGW_SPI_MUX_MODE0;
     spi_device = *(int *)spi_target; /* must check that spi_target is not null beforehand */

This file has been truncated. show original

I believe what they are doing is actually splitting an SPI “transfer” operation used as a “read” into two distinct SPI operations without a change of the /CS pin in between:

First they do a “write” to send the command such as the register to be read, the result of this would be ignored.

Then they do a “read” to get the data

As far as the SX1301 is concerned this is a single bi-directional transaction (as the chip select does not change), but as far as the MT7628 is concerned, it is two distinct operations, a write followed by a read.

Clever!

Tony_Smith · September 22, 2019, 8:06pm

Thanks for the explanation, most appreciated.

billkas · November 21, 2019, 2:46pm

Good evening everyone I got a RAK2246 96 Board can someone give me a guide with all its links to raspberry.
We can find the board below and its connection?
Τhank you in advance.

ZhuQI · November 22, 2019, 2:56am

@billkas

If you are using rak’s firmware, you can find related tutorials here.

https://doc.rakwireless.com/rak7243c-pilot-gateway/configuring-the-gateway#connect-through-lte-only-for-the-cellular-version

Tony_Smith · December 1, 2019, 7:48am

Here are the connections you need between a RAK2245 Stamp Version (use the Edge Connections) or the RAK2245 96 Boards (use the 40 pin socket). You can use the edge connection on the 96 Board version if you like.

You can find the layout on the RAK web site -
96 Board
https://downloads.rakwireless.com/en/LoRa/RAK2245-96Boards/Hardware-Specification/RAK2245-96Boards_User_Manual_V1.2.pdf
Stamp Version

Raspi             RasPi Name	RAK2245 	RAK2245        RAK Description
Physical                        Edge            96 Board
Connection		        Connections     Connector

1	           3.3 Volt     A4	        35             IO Reference
2	           5 Volt       A3              37             5 volt
4                  5 Volt       A3              37             5 Volt
6                  Gnd          A1, A2,         1, 2, 39, 40   Gnd
                                B1, B2, C1, C2,
                                C3, C4, C5 ,C6	
11                 GPIO 17      A13             6              Radio Reset
19                 SPI 0 MOSI   A8              14             SPI0_DOUT
21                 SPI 0 MISO   A10             10             SPI0_DIN
23                 SPI 0 SCLK   A11             8              SPI0_SCLK
24                 SPI 0 CE0    A9              12             SPI0_CS

nograin · February 25, 2020, 12:22pm

curious if you got any further with this - just starting to research how to get things going with an Onion Omega Pro - inspired by @Tony_Smith’s tube-design i had seen on the TTN forum i’ve also gone looking for emmc-based options and ended up with the onion.

(gerne auch PM auf deutsch )

cstratton · April 30, 2020, 5:41pm

The Onion is an MT7688 so based on an SPI flash not an eMMC - in actuality that probably makes it a bit more robust than even an eMMC.

You can probably with some effort adapt the codebase for RAK’s MT7628 based kits. Beware there’s a kernel SPI patch needed, and then you need to make a corresponding SPI patch to the packet forwarder’s LoRa HAL.