Theory Of Operation; Processor Board - LeCroy Waverunner2 Series Service Manual

4.

Theory of Operation

4.1

Processor Board

MPC603e Processor
The PowerPC603e on the processor board is a 64-bit RISC processor having
2x32Kbyte cache and features high speed processing and quick memory access.
The processor is designed to operate with an internal clock which is 5 times the
external bus clock cycles and is used under the 32bit mode.
The board consists of two circuit-blocks:
•
The 32bit block, that contains the main PowerPC processor, synchronous
dynamic RAM module, VGA interface, Super-I/O and main board interface.
•
The 8bit block, which incorporates all peripherals and other interfaces for outer
connections.
These two circuit-blocks are connected through MC68150 (dynamic bus sizer).
Power Supply
The board requires two power sources (Vcc and +12V). +12V source is used for
OP-amps and small-peripheral operation.
The processor requires 3.3V and 2.5V, and some other logic devices are operated
by the +5V source. All of the signals are TTL compatible.
An OP-amp and MOSFET transistor comprise the 3.3V and 2.5V power source. The
reference voltage is taken through the voltage-resistor divider network across the
+5V power source.
32bit Peripherals
There are 5 devices on the processor's 32bit data bus:
•
VGA video controller
•
S-DRAM system
•
bus sizer, an interface to 8bit circuit-block
•
Super-I/O
•
MAIN board
Theory of Operation 4-1