Panasonic KX-HCM280, Service Manual

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FLASH MEMORY (IC102)
Operating Power Supply: +3.3V
Package: 48 pin TSOP
Capacity: 16Mbit, Access Time: 90ns
Stores programs and MAC Addresses, which are read in by the CPU for operation.
Stores user set values also.
An upgrade from 10/100 BASE-Tx is possible.
SDRAM (IC103)
Operating Power Supply: +3.3V
Package: 54 pin TSOP
Capacity: 64Mbit
Stores the memory for CPU work and temporary saved images.
DEFAULT SW (SW101)
Pressing the default SW can return the set point of the network camera to factory-settings.
14.1.2. LAN Block
LAN CONTROLLER (IC501)
Operating Power Supply: +3.3V
Package: 128 pin TQFP
Operating Clock: 25MHz (X501)
Automatic switching (auto negotiation) of 10BASE-T/100BASE-TX Built-in transmit-receive 8KB
FIFO
The LAN interface consists of IC501 and RJ-45 module with a built-in transformer (CN5).
LAN PACKET SIGNAL FLOW
When transmitted
1. While the Camera is sending data to the network, the CPU (IC101)
reads the data from the SDRAM (IC103).
2. The data is present on the data port of the LAN Controller (IC501).
3. The LAN Controller writes the data, which was written on the data
port, into the Transmission Buffer, using the built-in Remote DMA.
4. Repeat the steps above from 1 to 3 for one packet.
5. Receives a transmission command from the CPU, and transfers
the data from the Transmission Buffer to the FIFO, using Local
DMA.
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