Configuration Examples - Espressif Systems ESP8266 SDK Getting Started Manual

!
Option
bit 1
{bit 3，bit 2}
113 byte
6.3.3. Configuration Examples
The configuration of bytes 112 and 113 depends depends on users' specific needs. We
provide some examples below:
1. The module works at ambient temperature, and needs no correction of the
frequency offset.
Set byte 112 = 0, byte 113 = 0.
•
2. The module works at ambient temperature and needs no automatic tracking and
correction of the frequency offset; yet the frequency offset is large. In this case, a
manual correction of the frequency offset is recommended.
• If the frequency offset is +160 KHz (at ambient temperature), users can set byte 112
= 0x07, byte 113 = (256 - 160/8) = 236 = 0xEC.
If the frequency offset is -160 KHz (at ambient temperature), users can set byte 112 =
•
0x05, byte 113 = 160/8 = 20 = 0x14. This may effect the digital peripheral
performance, so we do not recommend it.
3. Applications, such as smart lights, work at a wide temperature range of -40 °C to
125 °C, and need to track and correct the frequency offset automatically. The
frequency offset at ambient temperature is small, so the initial offset correction
value is not needed.
Set byte 112 = 0x03, byte 113 = 0.
•
Espressif
The default value of byte 112 is 0.
When value = 0, it means that the bbpll is 168 M. Both positive and negative
frequency offsets can be corrected.
However, this may effect the digital peripheral performance and, therefore, it is not
recommended.
When value = 1, it means that the bbpll is 160 M. Only the positive frequency offset
can be corrected.
When value = 0, it means that the chip will track and correct the frequency offset
automatically. The initial correction value is 0. When value = 1, it means that the chip
is manually programmed to change the frequency offset to that of byte 113, so the
chip will not track and correct the frequency offset automatically. When value = 2, it
means that the chip will track and correct the frequency offset automatically. The
initial correction value is that of byte 113.
The default value of byte 113 is 0.
It is the value when the frequency offset is corrected manually or the initial correction
value in frequency tracking. The data type is sign int8, in multiples of 8 kHz.
28 33 ! /!
6. Downloading the Firmware
Description
2017.05