MICRF620 Micrel Inc, MICRF620 Datasheet - Page 8
![](/photos/40/78/407821/micrf62011_5x14_1mm_sml.jpg)
MICRF620
Manufacturer Part Number
MICRF620
Description
Manufacturer
Micrel Inc
Datasheet
1.MICRF620.pdf
(21 pages)
Specifications of MICRF620
Operating Temperature (min)
-20C
Operating Temperature Classification
Commercial
Modulation Type
FSK
Lead Free Status / Rohs Status
Not Compliant
Writing to the Control Registers in MICRF620
Writing: A number of octets are entered into MICRF620,
followed by a load-signal to activate the new setting.
Making these events is referred to as a “write sequence.” It
is possible to update all, 1, or n control registers in a write
sequence. The address to write to (or the first address to
write to) can be any valid address (0-21). The IO line is
always an input to the MICRF620 (output from user) when
writing.
What to write:
How to write:
Bring CS active to start a write sequence. The active state
of the CS line is “high.” Use the SCLK/IO serial interface to
clock “Address” and “R/W” bit and “Values” into the
MICRF620. MICRF620 will sample the IO line at negative
edges of SCLK. Make sure to change the state of the IO
line before the negative edge. Refer to figures below.
Bring CS inactive to make an internal load-signal and
complete the write-sequence.
The two different ways to “program the chip” are:
Writing to a Single Register
Writing to a control register with address “A6. A5, …A0” is
described here. During operation, writing to 1 register is
sufficient to change the way the transceiver works. Typical
example: Change from receive mode to power-down.
Micrel, Inc.
July 2006
Field
Address:
R/W bit:
Values:
•
•
•
•
•
The address of the control register to write to (or if
more than 1 control register should be written to,
the address of the 1
A bit to enable reading or writing of the control
registers. This bit is called the R/W bit.
The values to write into the control register(s).
Write to a number of control registers (0-22) when
the registers have incremental addresses (write to
1, all or n registers)
Write to a number of control registers when the
registers have non-incremental addresses.
Table 2. Writing to the Control Registers
Comments
A 7-bit field, ranging from 0 to 21. MSB is written first.
A 1-bit field, = “0” for writing
A number of octets (1-22 octets). MSB in every octet is written
first. The first octet is written to the control register with the
specified address (=”Address”). The next octet (if there is one) is
written to the control register with address = “Address + 1” and so
on.
st
control register to write to).
8
In addition, 1 octet with programming bits is entered. Totally, 2
octets are clocked into the MICRF620.
How to write:
In Figure 1, IO is changed at positive edges of SCLK. The
MICRF620 samples the IO line at negative edges. The
value of the R/W bits is always “0” for writing.
Writing to All Registers
After a power-on, all writable registers must be written.
This is described here.
Writing to all register can be done at any time. To get the
simplest firmware, always write to all registers. The price
to pay for the simplicity is increased write-time, which
leads to increased time for changing the way the
MICRF620 works.
What to write
In total, 23 octets are clocked into the MICRF620.
CS
SCLK
IO
Field
Address:
R/W bit:
Values:
Field
Address:
R/W bit:
Values:
Table 3. “Address” and “R/W bit” together make 1 octet.
Table 4. “Address” and “R/W bit” together make 1 octet.
•
•
•
Figure 1. How to write to a single Control Register
Bring CS high
Use SCLK and IO to clock in the 2 octets
Bring CS low
Comments
‘000000’ (address of the first register to write to, which is 0)
“0” for writing
1
values for ControlRegister1 and so on for all of the octets. So the
22
specific sections of this document for actual values.
A6
st
Address of register i
nd
Comments
7 bit = A6, A5, …A0 (A6 = msb. A0 = lsb)
“0” for writing
8 bits = D7, D6, …D0 (D7 = msb, D0 = lsb)
Octet: wanted values for ControlRegister0. 2
octet: wanted values for ControlRegister21. Refer to the
A5
A0
RW
RW
D7
MICRF620/MICRF620Z
Data to write into register i
Internal load pulse made here
D6
M9999-120205
D2
nd
Octet: wanted
D1
D0