Softdev 132 questions

RE: Softdev 132 questions

scrungy_doolittle — Wed, 09 Jun 2021 19:55:55 GMT

I have the development kit and a board, but that doesn't help me with laying out a schematic.

"soft device" implies that it does more than just the bluetooth stack. Do you have to have custom code running in it just to use it as a dumb uart? or is there a uart characteristic, and if so, how is the buffering, cts/rts handled?

RE: Softdev 132 questions

awneil — Wed, 09 Jun 2021 16:06:14 GMT

[quote userid="13550" url="~/f/nordic-q-a/76160/softdev-132-questions/314531#314531"]The PCA10040 h file applies only to the dev board[/quote]

You would create your own version for custom hardware

[quote userid="13550" url="~/f/nordic-q-a/76160/softdev-132-questions/314531#314531"] I cannot find any information on what pins on the nRF52832 are tied up by the bluetooth stack.[/quote]

AFAIK, It doesn't use any - other than dedicated pins like antenna, crystal, etc.

Again, the way to prototype this & work this stuff out would be with a DK ...

RE: Softdev 132 questions

scrungy_doolittle — Wed, 09 Jun 2021 14:48:01 GMT

The PCA10040 h file applies only to the dev board.

The issue right now, is that I am not developing code, rather I am *working on a schematic*. I want to set the BT832 up in a similar way to the RN4020 initially, so that it functions as a simple bluetooth uart, at 115,200 baud, with hardware handshaking. Once we have it running, then I want to add code to the module, to capture all traffic in from the bluetooth, and manage what goes out to the bluetooth. The device that it is connected to, will periodically transmit status information to the BT832 over the serial port, using a hardware delimited protocol (The BT832 will have to monitor a line, and that should generate an interrupt). The BT832 will then repackage the information into a packet to send to the bluetooth link. In addition it will accept command packets from the bluetooth, manipulate them and repackage them to be sent to the uart to the device under control. I need a certain number of input and output linesI prefer to use the castellated pins so we don't have to try to deal with the LGA pins. Lines needed other than the TX/RX lines, are connect output, true when something connects, a reset line to reset the module, a CMD/DATA line, a line for a hardware delimited packet (i.e. the line goes high, the packet goes out the uart to the bluetooth, and then the line goes low. A second handshaking line for a status line to indicate the length of the packet. A line that tells me when the device is in sleep mode, and a line that can wake the device out of sleep mode. That is 6 I/O pins. Near field communication is nice, but not necessary. Our assembly house can build the LGA connections, but it would be nearly impossible to replace the module if we went that route.

I was not talking about modifying the bluetooth stack, but adding user application code later, such that it can capture all bluetooth traffic, enforce limits on who can connect, and control a secondary device. I don't understand the mechanics of doing that.

More importantly, I cannot find any information on what pins on the nRF52832 are tied up by the bluetooth stack. Does it use a pin for connection status?

Does it use rts/cts for it's uart?

What determines the pin usage on the module (which while it is not a nordic module, IS based on a nordic nRF.

RE: Softdev 132 questions

awneil — Wed, 09 Jun 2021 09:07:34 GMT

[quote userid="2133" url="~/f/nordic-q-a/76160/softdev-132-questions/314297#314297"]The SWD lines nor the ADC or reset pins can be moved. (and the obvious, crystals and power and ground pins and RF out (ANT) . [/quote]

There's also few other pins that have "restrictions" - eg, NFC pins, and pins near the antenna - this is all documented in the Product Specification

https://infocenter.nordicsemi.com/topic/struct_nrf52/struct/nrf52832_ps.html

RE: Softdev 132 questions

Jay Tyzzer — Tue, 08 Jun 2021 22:03:44 GMT

You can change the UART TX and RX location in the PCA10040.h file found in the BLE examples in the SDK. Note that it may say "Pin number" but it really means the GPIO number.. so TX = pin 8 is really GPIO PO.8.

The SWD lines nor the ADC or reset pins can be moved. (and the obvious, crystals and power and ground pins and RF out (ANT) .

You may wish to also erase the module first as some modules come with "middle ware".

As far as modifying the Softdevice... This is a precompiled binary and the source code is not distributed.

RE: Softdev 132 questions

awneil — Tue, 08 Jun 2021 20:42:19 GMT

[quote userid="13550" url="~/f/nordic-q-a/76160/softdev-132-questions"]

How can you add custom code to the soft device? Is there a tutorial somewhere?

[/quote]

The SoftDevice is the BLE stack - all of the SDK BLE examples use a SoftDevice:

https://infocenter.nordicsemi.com/topic/sdk_nrf5_v17.0.2/examples_ble.html

I would suggest that you spend some time with an nRF52-DK to gain familiarity with the product, tools, etc before moving on to a custom design

https://www.nordicsemi.com/Software-and-Tools/Development-Kits/nRF52-DK