A26 Cpu Assembly Description - Agilent Technologies PSA Series Service Manual

Troubleshooting the Processor, Power Supply, and Display

A26 CPU Assembly Description

A26 CPU Assembly Description
Purpose. The A26 CPU (processor) assembly consists of three boards:
the base CPU processor board, the A26A1 128M DRAM card, and the
A26A2 Flash memory board.
The operating system, the main firmware, measurement applications,
and the IP address and saved states, are stored in Flash memory. If the
original CPU board fails, all this information can be transferred to a
replacement CPU board by transferring the A26A2 Flash board.
The CPU board contains the instrument serial number.
There are several I/O connections on the rear panel of the instrument.
Many of these connectors are soldered directly into the CPU board or
plug into the CPU. These connections include the following:
• SCSI-2 connector. (Factory use only)
• Parallel interface connector. Used to connect the instrument to a
parallel printer.
• LAN connector. Used for instrument control and for downloading
firmware into the instrument.
• GPIB. Used for instrument control and automated testing and
remote control operation.
• Keyboard connector. Used for connecting an external PS-2 keyboard.
Keyboard functionality is limited to factory/field service.
• RS-232 connector. (Factory use only)
• VGA monitor output connector. Used to connect an external,
non-interlaced VGA compatible monitor with a signal that has
31.5 kHz horizontal/60 Hz vertical synchronization rate.
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