Datasheet

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DP83849C
7.2.5 LED Direct Control Register (LEDCR)
This register provides the ability to directly control any or all LED outputs. It does not provide read access to LEDs. In
addition, it provides control for the Activity source and blinking LED frequency.
Table 37. LED Direct Control Register (LEDCR), address 18h
Bit Bit Name Default Description
15:9 RESERVED 0, RO RESERVED: Writes ignored, read as 0.
8 LEDACT_RX 0, RW 1 = Activity is only indicated for Receive traffic
0 = Activity is indicated for Transmit or Receive traffic
7:6 BLINK_FREQ 00, RW LED Blink Frequency
These bits control the blink frequency of the LED_LINK output
when blinking on activity is enabled.
0 = 6Hz
1 = 12Hz
2 = 24Hz
3 = 48Hz
5 DRV_SPDLED 0, RW 1 = Drive value of SPDLED bit onto LED_SPEED output
0 = Normal operation
4 DRV_LNKLED 0, RW 1 = Drive value of LNKLED bit onto LED_LINK output
0 = Normal operation
3 DRV_ACTLED 0, RW 1 = Drive value of ACTLED bit onto LED_ACT/LED_COL output
0 = Normal operation
2 SPDLED 0, RW Value to force on LED_SPEED output
1 LNKLED 0, RW Value to force on LED_LINK output
0 ACTLED 0, RW Value to force on LED_ACT/LED_COL output