TD1208/TD1508
TD1508 is the FCC version of the TD1208, they are pin to pin compatible and based on the same SDK so converting an object working on a TD1208 sounds easy. Practically speaking there are some preparing steps because of some tiny bugs to solve.
Let see how to port a Telecom Design existing firmware for TD1208 to TD1508 (from ETSI to FCC).
Measuring a pulse duration in a pulse train was my last week headache with the TD1208 and the not so well documented EFM32. Basically, my objective was to activate a timer on a pulse train to measure the duration of the pulse. This duration was measured about 100uS and occurred at 1 Hz.
My choice was to rise an interrupt on each signal front (raising and falling) and measure the duration between the two first interrupt call. Some reset function ensure we are measuring the low state duration (100uS) not the high state duration (1s). This part will not be described here. The purpose of this post is to describe the main hole I fallen in.
For flashing a TD1204 / TD1208 over J-link you need to use the following commands:
JLinkExe -device EFM32G210F128 -if swd -speed 1000 J-Link> loadbin xxxxx.bin,0 ... J-Link> r # reset J-Link> g # go
Total programming time is about 5 seconds. The circuit between the segger connector and the TD is the following one. (do not forget to connect VDD circuit to Segger VTref.
td1204 / j-link cable
Telecom Design TD1204 have really limited number of GPIOs available even if it have many pins 🙁 … So you quickly have to use the DB2-DB3 pin that are usually used by SWD port.
If you try to reconfigure directly the Pin, this will not work until you inactivate SWD. For this, you must call first the following functions :
GPIO_DbgSWDIOEnable(false); GPIO_DbgSWDClkEnable(false);
…
A good way to expand Telecom Design system is to use I2C to connect external devices. As an example I had to add an extra Analog to Digital converter. I’m using a MCP3021Ax device. This I2C chip just return a 10bits value each time you send a READ at the expected address. This post contains the TD1204 code to configure I2C and get the data back
TD1204 / Sigfox & GPS
Telecom Design provides 4 different chips to support SigFox communications. This post details the differences of each of them in term of functionnalities
All are modules are based on a EFM32 / Cortex M3 micro-controler with 128KB flash, 16KB RAM, ultra low power including a Silicon Labs transceiver. The chip is a EFM32G210F128
Read more for details
Sigfox on Raspberry Pi
Based on my sigfox multi-board shield, it is possible to hack sigfox with a raspberry pi. The standard telecom Design firmware allow to use it as a modem. The raspberry Pi just have to send the expected AT commands
I previously write this post on how to use a BeagleBoneBlack as a JTAG (SWD) programmer. It was fun but really slow. I port my code on RaspberryPI and now what was taken 5-8 hours is a couple of minutes.
To connect the SWD connector to the PI use the following schema
Connect SWD to RaspberryPi
I use this peace of code to reflash my TD1204 and TD1208 based both on EFM32 when bricked after unsuccessful update…
Here is the python file to interact with SWD : https://github.com/disk91/PySWD/blob/master/RpiGPIO.py
I hop it will be soon integrated in the main PySWD project as the previous one.
You should check or modify flashEFM32.py file
import array from PirateSWD import * from RpiGPIO import * from SWDCommon import * [...] def main(): busPirate = RpiSWD("", vreg = True) debugPort = DebugPort(busPirate) efm32 = EFM32(debugPort)
To run the Flash program, just launch
# ./flashEFM32.py ../myProgram.bin