Service manual

Ultraview 1030/1050 Monitors — Service Manual
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EMI Reduction
The CPU PCBA includes several design features intended to reduce EMI effects. The power
supply connections throughout the PCBA are segmented and heavily filtered to prevent noise
propagation from one part of the PCBA to another. All high frequency signals are driven through
series resistors to limit the rise and fall times of these signals, reducing ringing and other EMI
effects. The construction of the multi-layer PCBA is such that noisy signals are shielded by power
and ground planes.
Boot Sequence Overview
When power is applied, the unit begins its boot up sequence. The following is a highly abbreviated
version of the sequence of events that occurs while the unit is booting.
1 Program execution starts at address 7F000100 in Flash.
2 Key internal and external devices and memories are mapped and enabled.
3 The boot-type value is read from super-cap-backed SRAM. This value is written to SRAM at
every power down or self-reboot. The value determines the kind of boot, warm or cold. Warm
booting skips diagnostics and other steps in order to boot as quickly as possible.
4 Key areas of DRAM are tested (cold boot only).
5 The boot code is copied from Flash to DRAM and program execution resumes in DRAM.
6 More internal and external devices are initialized.
7 Other key memory and CPU tests are performed (cold boot only).
8 The VxWorks kernel is started.
9 Drivers needed for diagnostics and the boot console are installed.
10 Diagnostics are run (cold boot only).
11 Boot logo and the 3-2-1 countdown are displayed (cold boot only).
12 The application code is copied from Flash to DRAM and executed in DRAM.
13 Much of the above initialization is repeated, less all testing, this time as part of the application
code.
14 Normal monitor operation begins.
Normal Operation Overview
This is a very high-level summary of what the software does as part of its normal operation.
Once the unit is booted it begins normal monitor operation. Normal operation can be viewed as
several high-level Ultraview Care Network software subsystem tasks running simultaneously.
These interface to other tasks, and all the tasks interface to hardware devices via software called
device drivers.