Device Functional Modes - SG Micro SGM5200 Manual

SGM5200
DETAILED DESCRIPTION (continued)

Device Functional Modes

There are three modes for channel sequencing, namely
manual mode, auto-1 mode and auto-2 mode. Mode
selection is done by writing into the mode control register
(refer to Table 1, Table 2 and Table 5). A new multiplexer
channel is selected on the 2
shown in Figure 1) in all three modes.
Manual Mode
When configured to operate in manual mode, the next
channel to be selected is programmed in each frame and
the device selects the programmed channel in the next
frame. On power-up or after reset the default channel is
'channel 0' and the device is in manual mode.
Auto-1 Mode
In this mode, the device scans pre-programmed channels in
ascending order. A new multiplexer channel is selected
nd
every frame on the 2
separate program register for pre-programming the channel
sequence. Table 3 and Table 4 show auto-1 program
register settings.
Once programmed the device retains program register
settings until the device is powered down, reset or
reprogrammed. It is allowed to exit and re-enter the auto-1
mode any number of times without disturbing program
register settings.
The auto-1 program register is reset to "FFFF" hex for
SGM5200 upon device power-up or reset; implying the
device scans all channels in ascending order.
Auto-2 Mode
In this mode, the user can configure the program register to
select the last channel in the scan sequence. The device
scans all channels from channel 0 up to and including the
last channel in ascending order. The multiplexer channel is
selected every frame on the 2
is a separate program register for preprogramming of the
last channel in the sequence (multiplexer depth). Table 6
lists the auto-2 program register settings for selection of the
last channel in the sequence.
Once programmed the device retains program register
settings until the device is powered down, reset or
reprogrammed. It is allowed to exit and re-enter the auto-2
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Channel Sequencing Modes
nd
falling edge of SCLK (as
falling edge of SCLK. There is a
nd
falling edge of SCLK. There
12-Bit, 1MSPS, 16 Channels,
Single-Ended, Serial Interface ADC
mode any number of times without disturbing program
register settings.
On power-up or reset the bits DI[9:6] of the auto-2 program
register are reset to "F" hex for SGM5200; implying the
device scans all channels in ascending order.
Device Programming and Mode Control
The following section describes device programming and
mode control. The device features two types of registers to
configure and operate the device in different modes. These
registers are referred as configuration registers. There are
two types of configuration registers namely mode control
register and program registers.
Mode Control Register
A mode control register is configured to operate the device
in one of three channel sequencing modes, namely manual
mode, auto-1 mode and auto-2 mode. It is also used to
control user programmable features like range selection,
device power-down control. GPIO read control and writing
output data into the GPIO.
Program Registers
The program registers are used for device configuration
settings and are typically programmed once on power-up
or after device reset. There are different program registers
such as auto-1 mode programming for preprogramming the
channel sequence, auto-2 mode programming for selection
of the last channel in the sequence, alarm programming for
all 16 channels and GPIO for individual pin configuration as
GPI or GPO or a pre-assigned function.
The device power-up sequence is shown in Figure 5. By
default, the mode control register is configured for manual
mode and the default channel is channel 0. As explained
previously, the device
configure user programmable features like GPIOs, Alarms
and to preprogram the channel sequence for auto modes.
At 'power-up or on reset', these registers are set to the
default values listed in Table 1 to Table 9. On power-up or
after reset, it is required to program mode control register
and program registers to required mode of operation. Once
configured, the device is ready to use in any of the three
channel sequencing modes namely manual, auto-1 and
auto-2.
Device Power-Up Sequence
offers program registers to
SEPTEMBER 2021
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