[quote author="krex3c"]Hi, i am using / playing with a STM32VLDiscovery Board at the moment, but also bought a STM32F4 Discovery (but not tested yet, and the STM32F3 also looks cool). I just wanted to do some NFC experiments with my Nexus S.
How much work is it, to port the TI MSP430 sources to a STM32 µC?
Is Chibi-OS an advantage for this? I already looked at this OS earlier, and it seems really cool, especially for the STM32 Controller; but as having no experiences with a RTOS, in the moment i am working with simpler program structures like state machines, and the ST standard peripheral libraries.[/quote]
Porting TI MSP430 EVM code to ChibiOS takes me about 5 days of work (for a basic portage), it requires to use ChibiOS driver and rewrite the interrupt events and cleanup lot of stuff everywhere in the code as there is lot of code specific to MSP430. For a proper stuff I will advise to rewrite all from scratch because finally the ported code was like a full rewrite at end.
Anyway for such fast result you need a good knowledge of ChibiOS/driver and how the MSP430 code work (with very good knowledge of TRF7970A datasheet) as it is full of trap and bugs, but it is a very good starting point especially for a demo or to quickly check basic stuff like reading UID ...
So to do that from start without knowledge on TRF7970A, it can takes between 2 weeks and 1 month(it is more realistic) depending on your own experience on C/driver and how low level stuff work(including datasheet and testing with oscilloscope and logic analyzer). Anyway the most consuming task was to develop the NFC sniffer but it's an other part as it requires tons of tests and hacking because of usage of non documented part in TRF7970A and also because it requires DMA and custom drivers with hard real-time (to output decoded symbol in real-time during sniffing).
Of course the TRF7970A work in any mode PASSIVE or ACTIVE. In my own application I use Passive mode and special registers to sniff data received & sent by a TAG in order to debug transfer or learn new protocol.
About code available for PASSIVE Target like to emulate a TAG there is no code available (the code in TI EVM is not working and commented IIRC) and I have not implemented this mode but it is well described in datasheet, when I will have some spare time I will probably try to implement it. About using it with MSP430 I cannot reply as I use a bigger MCU the STM32F4 which is enough for all NFC mode and especially sniffing which requires lot of CPU power to sniff and decode frame in realtime at up to 848KHz.
For the last question how to modify TRF7970A register just look at TRF7970A EVM GUI it is Windows GUI software to do that and test lot of stuff. This PC software work with TRF7970A EVM firmware of the TRF7970A EVM board (MSP430), but I have ported the code to STM32F4 too.
If you want more details you can check my blog http://titanmkd.blogspot.com as I even explain how to read UID of NFC card with just a Bus Pirate.
In fact all is my own work (and developed only by me hw & sw side) and it was intended to be sell to a company and because this company declined the offer, because maybe they was thinking they could have all for free when the full source code and hw will be open source as it was planned, so I decided to do not publish it. So for those really interested you can contact me to obtain hw + sw for very good price (especially if it is for non commercial use).
[quote author="arupbsk"]Nice PCB 3dview, but isn't it missing a current sense resistor or pcb trace loop for current measurement?[/quote] No there's no any sense resistor as it is a tool to be used with a multimeter. In fact you just need to plug multimeter in current/amp mode in measure current pins. The best is to connect a uCurrent with burden voltage take into account to measure accurately device with very low power consumption.
Of course it is maybe not the best deal but shipping is just too expensive and for shipping without tracking (just express) it can be even lower price or why not a DIY package including the components. But anyway it is just an offer and I do not really win any money on that considering the time spent to package PCB and send them in low quantity.
For those interested in a cheap funny board to test USB current consumption/voltage or even check USB D+/D- and ID signal I have designed a new PCB board Current Voltage Tester v1.0 Rev1 (Size 50mm x 31mm). Current or Voltage can be measured using standard Banana Plug Connector (for voltmeter) or a standard header. The PCB include also easy access with Oscilloscope to D+, D- and USBID pin for checks.
See photo of the board hereafter: [attachment=0]
A very cheap case is also planned depending on feedback about that board.
Nota: For those interested I plan to buy 10 PCBs and I could sell some bare PCB for very good price (like 10 Euros including shipping for Europe for 2 PCB). If lot of people are interested by more PCB I could lower the price and buy a batch of 20 or 50 PCB and sell them for even less (like 20 euros for 5 PCB including shipping), for information all PCB will be 100% E-test. Contact me in the forum or by email titanmk@gmail.com
Yes now this ATX Breakout board is really useful I was waiting adjustable power !! If there's any spare PCB i'm ready to buy one (with a box ;) Best Regards Benjamin
I'm sorry but because of a problem with a company I will not release the design publicly If you are interested by the full design and depending on project contact me by email with your project Best regards Benjamin
To execute code in RAM instead of FLASH you need to modify (or copy and modify) the GCC linker script (LD) It is here in chibios F:SVNSTM32F4DISCOVERYchibiostrunkosportsGCCARMCMxSTM32F4xxldSTM32F405xG.ld for example And change the code (.text ...) to be in RAM instead of FLASH then you just load the code using JTAG/SWD and GDB and you run it. Warning before to run the code in RAM there's also modifications to do for vector table to relocate it in RAM instead of FLASH addr 0x08000000 by default. To do that you need to change SYSCFG_MEMRMP (it is physical remap) to the address in RAM 0x20000000 (should be done through debugger script) For more details on Physical Remap look the Reference Manual STM32F407x see "Table 5. Memory mapping vs. Boot mode/physical remap" Anyway with this solution you will be limited by SRAM1 (112KB) so it can work only if code is smaller than 112KB. For my own use/test I prefer to use always default Flash because timing differs (even if Flash is expected to be 0 wait state there's some case where it is not really 0 wait states, especially for hard realtime stuff).
Nota: On my latest design there's access to BOOT0 and BOOT1 pins so now you can do the remap using resistor(10K) on those pins to VCC or GND depending on the option you need (so you will do not need script to change SYSCFG_MEMRMP because it will be done by boot option).
[quote author="matseng"][quote author="TitanMKD"]I use TI BQ24230 as LiPo charger, when charging it also power ON the board (it includes Power Path management with boost)with priority to max current for the board (and not for the Lipo charging) and all is managed by the chipset, also the charging can be disabled.[/quote]
Ah, that seems to be a nice and capable chip, a little bit pricey though. 8 times as expensive as the ubiquitous MCP73811 if/when only a simple charging solution is needed. But I'll definitely keep it in mind for future projects. Thanks.[/quote]
Yes I know such TI components are a bit expensive (even if they are cheaper at Mouser compared to DigiKey) but I have computed the total BOM and the total price for LiPo version including PCB is about 30 euros / 36US$ for one unit (this price does not include soldering components and tests), the version without LiPo including PCB is about 22 euros / 28US$ so the price is not so expensive for the LiPo version.
Also see as example an adapter/Interface board for TRF7970A Breakout v1.1 to STM32F4 Debug v1.0, I plan to do the same for debugger board (DFU adding USB0 connector+Debug conf) and also for Arduino for less than 5US$.
[quote author="alanh"]I don't see a way for one to set the two boot pins. That's one of the most overlooked features of any STM32 board and in my opinion makes it worthless as a eval board.
DFU mode gives people a way they can download code to it without using a SWD probe.
RAM mode allows one to download code to memory and perform quick turn-around iterative testing without having to re-write the flash each code change. Very useful when combined with a probe and GDB - just 'load foo_ramlinked.elf' & 'run'![/quote]
I just updated the design and now BOOT0 is also available on Header J2 and BOOT1 is available on Header J1 so now it will be possible to change boot option but it will requires an other little board to plug on top (it is planned with all jumpers options as it also requires to set lot of pins to GND or 3V3 to select USB DFU or other stuff). USB0 will be also routed on this little board in order to access DFU and flash the program without using any debugger.
