Panasonic DX-600 Service Manual page 235

LED
1. LINK LED (LED1)
The LINK LED normally illuminates when the LAN cable is connected and when a link pulse is
detected. Consequently, LED can be used to determine whether the 10Base-T/100Base-TX cable has
become disconnected (RX side).
2. Activity LED (LED2)
This LED illuminates when reception data is present on the LAN.
(The LED also illuminates when reception data for other devices is present.)
Signal Routing
1. LAN Transmission
a. Transfers the MMR coded data from Image Memory (FROM) to CPU (SC PCB) and converts the
MH coded data.
b. Transfer the MH coded data of CPU (SC PCB) to SDRAM.
c. Transfer the converted text data to buffer RAM on LAN controller (LANB PCB) sequentially.
d. The transmission packet is processed by FIFO transfer to buffer RAM and then converted for
Manchester code. Finally, they are converted for differential pair signal and transmitted to Internet.
2. LAN Reception
a. Processed received data for Manchester coded signal at LAN controller.
b. The decoded received packet goes to buffer RAM through the FIFO. The data stored in buffer RAM
is transferred to SDRAM (SC PCB) by requests from SC PCB.
c. Decodes the Base 64 for MH coded image data at SDRAM and transfers CPU (SC PCB).
d. Inputs MMR coded data from CPU transfers Image Memory (FROM).
Edition 1.0
235
DX-600/800
APR 2002