System Module - Silicon Laboratories Si4010 Software Programming Manual

7.14. System Module

This module contains a grouping of functions which perform tasks that are too specific and individual to justify
creating an entire module for them. It is a collection of system support functions.
7.14.1. System Module Functions
vSys_Setup
Description: Responsible for setting any global configuration variables that the system
functions might need. Must be called at the beginning of the user application.
Inputs:
biFirstBatteryInsertWaitTime: (BYTE) Amount of time to wait before shutting
down on the first battery insertion. Each LSb of this value represents a wait time of
40ms. Application can set it to 0 if bandgap is never turned off in the user applica-
tion.
See more details in the description of the vSys_FirstPowerUp function.
Outputs:
None
vSys_BandGapLdo
Description: This function controls the bandgap reference and LDO settings. All applica-
tion control of these is to be done through this function. This is due to restrictions on when
the bandgap can be turned off.
The bandgap can not be turned off when the vSys_Setup() function is called with the
biFirstBatteryInsertWaitTime argument of 0. There are 3 states that the bandgap and LDO
can be in. The following table describes the details.
biBandGapLdoCtrl
0
1
2
Note that the LDO can not be set to be bandgap-referenced when the bandgap is off. The
function does not allow the LDO to be set to 1.24 V when the bandgap is off.
State
Bandgap Off, LDO self-referenced
Bandgap On, LDO self-referenced
Bandgap On, LDO bandgap-referenced MTP and NVM Access
Rev. 1.0
Operable Portions of Chip
MCU, LED and anything not listed
below.
Temperature Sensor, LC, DIV, PA,
Transmission.
AN370
85