Spacelabs 91369, Руководство по обслуживанию

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Theory
91369 Service Manual 3-12
Remote Keypad (Optional)
The monitor supports the 90360 remote keypad. The communication from the keypad is through 940 nm
wavelength infrared, and processing is done in the Motorola MC68HC908 8-bit microcontroller.
Touchscreen Circuitry
An ELO Graphics Coach chip set is built into the CPU PCBA to handle all communication between the 5-wire
resistive matrix touchscreen and the MPC8270 CPU. In addition to the standard UART signals, additional
signals from the on-board touchscreen controller (touchscreen sense, wake up, and shutdown) are directly
routed to the MPC8270 GPIOs. The current drivers for the touchscreen are sourced from +3 VDC through fuse
F1.
Hardware Reset
Externally driven HRESET will cause the following:
• Initialize memory controller
• Initialize system protection logic
• Initialize interrupt controller
• Initialize parallel I/O pins
PCI Subsystem
The PCI subsystem interfaces directly to the PCI Bridge integrated into the MPC8270 processor ( Figure 3-4 ).
All accesses to the PCI devices are done through this bridge. The monitor supports up to five PCI devices, not
including the PCI module integrated into the MPC8270. Not all devices reside on the primary PCI bus. To keep
the design modular and simple, only the PCI/ISA bridge, PCI/PCI bridge, and video controller reside on the
primary PCI bus. The PCMCIA controller is placed on the secondary PCI bus through the PC/PCI bridge. The
USB keyboard and mouse are supported by a USB controller located within the Intel 82371, which is USB v1.1
compliant.