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4 busy_tx and rx_on states, 5 reset procedure – Rainbow Electronics AT86RF231 User Manual

Page 41

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41

8111A–AVR–05/08

AT86RF231

7.1.4.4

BUSY_TX and RX_ON States

The transition from PLL_ON to BUSY_TX state and subsequent to RX_ON state is shown in

Figure 7-6 on page 41

.

Figure 7-6.

PLL_ON to BUSY_TX to RX_ON Timing

Starting from PLL_ON state it is further assumed that the PLL is already locked. A transmission
is initiated either by a rising edge of pin 11 (SLP_TR) or by command TX_START. The PLL set-
tles to the transmit frequency and the PA is enabled.

t

TR10

= 16 µs after initiating the transmission the AT86RF231 changes into BUSY_TX state and

the internally generated SHR is transmitted. After that the PSDU data are transmitted from the
Frame Buffer.

After completing the frame transmission, indicated by IRQ_3 (TRX_END), the PLL settles back
to the receive frequency within t

TR11

= 32 µs in state PLL_ON.

If during TX_BUSY the radio transmitter is programmed to change to a receive state it automati-
cally proceeds the state change to RX_ON state after finishing the transmission.

7.1.4.5

Reset Procedure

The radio transceiver reset procedure is shown in

Figure 7-7 on page 41

.

Figure 7-7.

Reset Procedure

Note:

Timing figure t

TR13

refers to

Table 7-1 on page 42

, t

10

, t

11

refers to

Section 12.4 “Digital Interface

Timing Characteristics” on page 157

.

Time [µs]

0

x

16

x + 32

Time

t

TR11

t

TR10

Command

RX_ON

State

Block

PLL_ON

RX_ON

BUSY_TX

Pin

SLP_TR

PA

PLL

PA, TX

RX

PLL

or command TX_START

x

Event

State

Block

Time [µs]

Pin /RST

TRX_OFF

x + 40

[IRQ_4 (AWAKE_END)]

0

various

Time

>t10

t

TR13

>t11

XOSC, DVREG

XOSC, DVREG

x + 10

FTN