nRF52840 Hardware
PC10059 Dongle
I am in the process of writing and editing this as I learn the nRF52 system, both software and hardware. I have a bad memory so like to record in writing, as I learn, for my own sake. I offer this to any reader who is interested, bearing in mind that I am exploring as I go along and am not associated with Nordic or anyone else who knows much about the nRF52 for that matter.
The nRF52840 dongle (id PC10059) has white printing identifying connections. However, even with a USB microscope, my old eyes have difficulty reading it. Nordic kindly provide hardware drawings and other documentation but but my memory is so poor I prefer to annotate a photo of the actual module with all the details I need (plus eventually adding my own references for my circuits/software.
Although Nordic nRF52840 Dongle User Guide 28/11/2018 reads "The nRF52840 Dongle (PCA10059) is the preferred hardware to be used with the nRF Connect for Desktop software package to develop and test your nRF-based wireless solutions", a word of caution should be added. As far as I can detect the dongle is not really useful for debugging software without the addition of the hardware SDK and extra wires to permit that development kit to manage the processor on the dongle. Maybe, just maybe, you could equip the dongle to send serial data via the USB and use PRINT statements. IMHO that is not a good way of debugging. In addition (as far as I can tell), the SEGGER development software does not support direct loading to the dongle whilst plugged into a USB port. Really the only way is to get a full development kit (10056) and use that for developing software. The dongle is very useful for prototypes once the software is fully operational. If a reader knows better, then use the comments system below to explain how it is done, and I will correct the above.
Now, on to some detail:
For programming the dongle without using the USB I believe (but have not tried (maybe later)) that all that is needed is a one to one connection (i.e. pin 1 to pin 1 etc.) between P1 and the "debug out" connector on PCA10056. P1 is effectively the "debug in" of the PCA10059 AFAIK.
On the other hand, if you wish to use the TC2050 socket for the same purpose a brief warning regarding its use is in order. If it is decided to buy a cable from TAG-CONNECT to directly connect this dongle to the PCA10056 hardware development kit, then make sure that you take their advice and buy TC2050-IDC-NL-050 not the one with -ALL at the end. The reason is that the debug-out connector on the TCA10056 puts ground on pin 5 and the dongle provides VBUS (so perhaps KER-POUFF of whatever usb device you have plugged it into). Note also that TAG-CONNECT also recommend TC2050-IDC-NL over TC2050-IDC-NL-050 because the cable used is more robust. However, the TC2050-IDC-NL has a 0.1" pitch connector so you will need an adapter to plug it into the 0.05" pitch connector on the TCA10056.
I am also fuzzy as to why the TC2050 "socket" does not connect "reset" to pin 10 and what effect that will cause on its use.
(all to be checked - this is release one!).
Click above to download the SVG source if you wish to edit the file. Use Inkscape . The svg file consists of two images with vector graphics superimposed. I used The Gimp to edit the photograph but it is, to a first approximation, useless in annotating with arrows and text. Since the arrows and text remain objects, you can edit and/or delete them with Inkscape if you wish.
TC2050-IDC use
I annotated the TC2050-IDC gold plated connections on the nRF52840 dongle diagram. Those connections are not for soldering a socket (unlike P1 also documented) but for "in factory" programming of a blank board i.e. this can be done with no bootloader present on the dongle. The dongle is not set up to handle a retained plug (it has to be held in place by some external means). Also, you will need a development kit (at this moment I am not sure if the nRF52832 kit will suffice or whether you must have an nRF52840 HDK). There, you will find a 10 pin "debug output" plug which has to be connected to the TC2050 plug. Doing so disables the nRF52 chip on the HDK and enables the one on the dongle to be programmed (debugged I am not sure??).
The front side is easier to follow, but still a couple of items to note:
Click above to download the SVG source if you wish to edit the file. Use Inkscape . The svg file consists of a png image with vector graphics superimposed. I used The Gimp to edit the png photograph but Gimp is, to a first approximation, useless in annotating with arrows and text. Since the arrows and text remain objects, you can edit and/or delete them with Inkscape if you wish.
The Chengdu Ebyte nRF52840 module
This is a typical minature module with 1.27mm pin header separation. It has no USB circuitry so has to be programmed with a hardware development kit. There is no built-in 32.768KHz crystal either. I bought a couple direct from China mainly to see how hard they are to use for prototyping without the need for a PCB and oven soldering. There is a (to me) very confusing note in the module documentation saying that a "write protect" has been implemented given as a reason why someone could not program it. However, it is unclear whether this relates solely to programming using the bootloader or also programming using the serial protocol from the 10056 development kit. I hope to investigate. Not yet started this work. (Jan 2019)
Just a photo for the moment of CDEBYTE-E73-2G4M08S1C-nRF52840-BLE-5-0-Wireless-Transceiver-8dbm-120m-2-4GHz-Ceramic-Antenna
