why data can not be wrote into the registers of nRF52840

RE: why data can not be wrote into the registers of nRF52840

nicholasldf — Tue, 21 Mar 2017 03:36:07 GMT

thank you, butch, have fixed the problem of VDD, it can output 3.3V now.

RE: why data can not be wrote into the registers of nRF52840

nicholasldf — Tue, 21 Mar 2017 03:35:13 GMT

OK, I have fixed the problem that "how to set VDD output 3.3V", thanks to the "UICR Config Example."

need to add a file uicr_config.h to keil project, and add the following two line code to it, finally include it in the file main.c

const uint32_t UICR_ADDR_EXTSUPPLY attribute((at(0x10001300))) attribute((used)) = 0xFFFFFFFF;//Enabled

const uint32_t UICR_ADDR_REGOUT0 attribute((at(0x10001304))) attribute((used)) = 0xFFFFFFF5;//3.3V

for tx power, this is a good answer

devzone.nordicsemi.com/.../

The NRF_RADIO register is a restricted resource when you are running a SoftDevice (and I assume you do?). Hence, you can neither read from it nor write to it. The SD blocks the radio as well as some other hardware registers to prevent users to inadvertently change critical parameters during transmissions.

RE: why data can not be wrote into the registers of nRF52840

nicholasldf — Tue, 21 Mar 2017 02:30:31 GMT

thank you, butch.

(1) for UICR, page 22 of <S132_SoftDevice_Specification_v3.1.pdf> says:

Access to UICR is Restricted when SoftDevice enabled.

(2) for tx power:

devzone.nordicsemi.com/.../

There isn't any way to get the current TX power level from the stack, so if you need it you have to keep track of it in your application, based on your calls to sd_ble_gap_tx_power_set().

from this post , nordic's engineers says there is no way to read tx-power, because sd_ble_gap_tx_power_get() function is not exist.

devzone.nordicsemi.com/.../

The softdevice will not adjust TX power automatically while running. You can set the TX power level used by calling the function sd_ble_gap_tx_power_set(), or get the current level with the corresponding sd_ble_gap_tx_power_get() function. These functions can be called at any time as long as the softdevice is enabled.

from this post , nordic's engineers says softdevice will not adjust TX power automatically.

RE: why data can not be wrote into the registers of nRF52840

butch — Mon, 20 Mar 2017 14:27:40 GMT

I think you should read the Nordic documents about writing NV memory, and if you have problems, ask another question. Re tx power, my guess would be that the SoftDevice keeps its own memo about what tx power you have asked for, and sets the radio register TXPOWER dynamically, i.e. on the fly, and restores it to the default after every radio operation. Maybe there is a 'getter' function in the SD API that you can call to inquire what tx power is set. In other words, ask the SD instead of reading the radio register directly.

RE: why data can not be wrote into the registers of nRF52840

nicholasldf — Mon, 20 Mar 2017 02:29:41 GMT

butch and Turbo J , thank you.

if UICR are non-volatile, so how to modify its registers ? also, why sd_ble_gap_tx_power_set(8) don't take effect?

RE: why data can not be wrote into the registers of nRF52840

Turbo J — Sun, 19 Mar 2017 21:20:24 GMT

Yes, UICR is NVM and must be treated similar to flash.

RE: why data can not be wrote into the registers of nRF52840

butch — Fri, 17 Mar 2017 15:23:00 GMT

Are the UICR registers non-volatile, i.e. FLASH i.e. a simple assignment does not work?