Other Parts Discussed in Thread: DP83869
Hello Team,
we are using DP83869 in our design with following operating modes:
- (a) Media Conversion Between Copper and Fiber
- (b) PHY RGMII to BASE100-Fx Fiber Ethernet PMD connections (SFF)
The DP83869 is connected with a SFF. Frames are being correct received and transmitted in all below described configurations.
We have connected LEDs at LED_0 (Link, green) and LED_2 (activity, yellow) pin of DP83869 for indication purpose. The electrical connections of the LEDs are the same for configurations (a) and (b).
Both LEDs are active low mode and also configured automatically correctly in LEDS_CFG2.
The ports using media conversion 100BASE-T to 100BASE-Fx (a) the LEDs work according to data sheet.
The ports used as Fiber PHY (RGMII 100BASE-Fx PHY, (b)) the yellow LED (LED_2) acts funny:
- For LED_2_SEL = 0x01 only blinking of yellow LED_2 with RX not with TX. The same behavior has also been confirmed on LED_0 if reconfigured to 0x01.
- The data sheet in table 43, which indicates that 0x1 = RX/TX activity, can thus not be confirmed.
- Setting 0x2 = TX activity shows blinking only when sending frames out of the port as expected
- Setting 0x3 = Rx activity also only shows activity for frames being received at the port.
- With 0xB = link OK + blink on TX/RX activity, there is blinking for RX AND TX - good, but removing the cable (no link), the LED keeps blinking.
- In “Fiber mode” there is no “readback” from the PHY, if SFF has a link although fiber link LED works according to the datasheet?
We want to use LED_2 to indicate both RX and TX activity on the fiber ports (b), but not if there is no link. Is there any configuration that works for a fiber port for showing both RX/TX activity? Is there some kind of workaround?
Best regards,
Thilo
