MICRF507 datasheet(10/47 Pages) MICREL

10 / 47 page

Micrel, Inc.

MICRF507

October 2, 2013

Revision 2.2

Functional Description

Control (3-wire) Interface

General

The MICRF507 operation is controlled through a set of 8-

bit registers. The chip has a total of 23 readable registers

(addresses 0-22) of which 22 (addresses 0-21) are

writeable. Through this register set, the user can set the

MICRF507 in transmit or receive mode, program the

carrier frequency, and select a bit rate, among other

options.

Table 1 identifies all register bits. Table 26 gives more

detail and Table 27 shows the register fields grouped by

category, with don’t-care and mandatory bits omitted.

Some bits shown as ‘0’ or ‘1’ are mandatory bits and must

always be written with the values given. Other bits marked

as “-“ are “don’t care” bits.

Registers are accessed serially through the control

interface consisting of the CS, IO, and SCLK pins.

Positive-going pulses at SCLK serve to clock bits in and

out of IO at a rate determined by the user. When IO is an

input, falling edges of SCLK strobe each bit in; when IO is

an output, each bit appears at IO after the rising edge of

SCLK.

The IO is an input for entry of starting addresses, the R/W

bit, and bytes being written to registers, and an output for

bytes read from registers.

CS enables transactions at the control interface, active

high. Transitions at the other two pins are ignored when

CS is low. This allows the MICRF507 to share SCLK and

IO with other devices as long as they have separate CS

lines.

To start a transaction (with SCLK and CS initially low),

bring CS high. To end a transaction (with SCLK low), bring

CS low.

To write a bit into IO (when IO is an input); first bring SCLK

high and drive IO with the bit level to be input (in either

order, or simultaneously). Then bring SCLK low.

To read a bit out of IO (when IO is an output); first bring

SCLK high and read the level on IO. Then bring SCLK low

(in either order, or simultaneously).

The first byte to be clocked in during a transaction is made

of seven bits (MSB first) of register address followed by

the R/W bit, 0 for write, 1 for read. Then, one or more

bytes to be written to or read from registers are clocked in

or out respectively, always MSB first.

MICRF507 Datasheet(PDF) 10 Page - Micrel Semiconductor

MICRF507 Datasheet(HTML) 10 Page - Micrel Semiconductor

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

Datasheet Download

Link URL