BLUENRG-1 datasheet(22/173 Pages) STMICROELECTRONICS

22 / 173 page

Functional details

BlueNRG-1

22/173

DocID028866 Rev 1

3.5.1.2

Watchdog reset

The BlueNRG-1 contains a watchdog timer, which may be used to recover from software

crashes. The watchdog contains a 32-bit down counter, which generates an interrupt, if the

interrupt is not serviced, the watchdog will generate a reset. The watchdog Reset will Reset

the Flash controller, the Cortex-M0 and all its peripherals but it will not Reset the debug

circuitry of the Cortex-M0.

3.5.1.3

System reset request

The system reset request is generated by the debug circuitry of the Cortex-M0. The

debugger writes to the SYSRESETREQ bit of the “Application Interrupt and Reset Control

embedded software. The system reset request does not affect the debugger, thus allowing

the debugger to remain connected during the reset sequence.

3.5.1.4

Lockup reset

The Cortex-M0 generates an output LOCKUP that indicates that the core is in the

architected lock-up state resulting from an unrecoverable exception. The LOCKUP signal is

used to generate reset in the BlueNRG-1. This reset will affect the Cortex-M0, the Flash

controller, and all the peripherals. The LOCKUP signal does not Reset the Cortex-M0

debug circuitry.

3.5.2

Reset and wakeup reason decoding

The BlueNRG-1 provides a set of registers to identify the reason behind a reset and

wakeup generation. Two registers are used: CKGEN_SOC->REASON_RST and

CKGEN_BLE->REASON_RST. The possible reasons are listed below:

If the register CKGEN_SOC->REASON_RST = 0, according to the CKGEN_BLE-

>REASON_RST the possible reasons are:

Wakeup from IO9, IO10, IO11, IO12, IO13.

Wakeup from internal timer: BLE timer 1 or BLE timer 2.

POR or BOR

If the register CKGEN_SOC->REASON_RST is not 0, according to its value the

possible reasons are:

System reset

Watchdog reset

Lockup reset.

3.5.3

Switching to external clock

When the system is in preactive state (run from internal RO 16 MHz), the software

sequence to switch to active should include switch to external XO.

When the system uses an external XO at 32 MHz instead of 16 MHz, the following steps

need to be done:

In preactive state, operate as follow routine:

uint8_t config[] = { 0x02, 0x3A, 0x44, 0x00};

BLUE_CTRL->RADIO_CONFIG = 0x10000 | (uint16_t) (

(uint32_t)config & 0x0000FFFF );

while((BLUE_CTRL->RADIO_CONFIG & 0x10000) !=

0);

Set the bitfield MHZ32_SEL of register SYSTEM_CTRL, for the digital part.

Wait the state machine is in active state by using the follow routine:

BLUENRG-1 bảng dữ liệu(PDF) 22 Page - STMicroelectronics

BLUENRG-1 bảng dữ liệu(HTML) 22 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

bảng dữ liệu tải về

Link URL