Environmental Monitoring and Control Device
Datasheet
Chapter 6 Hardware Monitoring
The following sub-sections describe the Hardware Monitoring Block.
6.1
Input Monitoring
The EMC6D100/EMC6D101 Device’s monitoring function is started by writing a ‘1’ to the START bit in the
Ready/Lock/Start Register (0x40). Measured values from the analog inputs and temperature sensors are
stored in Reading Registers. The values in the reading registers can be accessed via the SMBus interface.
These values are compared to the programmed limits in the Limit Register. The out-of-limit and diode fault
conditions are stored in the Interrupt Status Registers.
Note: All limit and parameter registers must be set before the START bit is set to ‘1’. Once the start bit is set, these
registers become read-only.
6.2
Resetting the Hardware Monitoring Block
6.2.1 POWER ON RESET
All the registers in the Hardware Monitor Block, except the reading registers, reset to a default value when
power is applied to the block. The default state of the register is shown in the table in the Register
Summary subsection. The default state of Reading Registers are not shown because these registers have
indeterminate power on values.
Note: Usually the first action after power up is to write limits into the Limit Registers.
6.2.2 SOFT RESET (INITIALIZATION)
Setting bit 7 of the CONF register performs a soft reset. This bit is self-clearing. Soft Reset performs reset
on all the registers except the Reading Registers.
6.3
Monitoring Modes
The Hardware Monitor Block supports two Monitoring modes: Continuous Mode and Cycle Mode. These
modes are selected using bit 1 of the Special Function Register (7Ch). The following subsections contain
a description of these monitoring modes.
For each mode, there are two options for the number of measurements that are performed on each
temperature and voltage reading. These options are selected using bit 5 of the special function register
(7Ch). These options are as follows:
1. 128 measurements are averaged for the remote diode temperature reading and 8 measurements are averaged
for all voltage and the internal temperature reading.
SMSC EMC6D100/EMC6D101
Page 21
Rev. 09-09-04
DATASHEET
SMSC [ SMSC CORPORATION ]
