High Performance Two Port 10/100 Managed Ethernet Switch with
Datasheet
1.3Register Nomenclature
Table 1.2 describes the register bit attribute notation used throughout this document.
| Table 1.2 Register Bit Types |
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REGISTER BIT TYPE |
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NOTATION | REGISTER BIT DESCRIPTION |
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R | Read: A register or bit with this attribute can be read. |
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W | Read: A register or bit with this attribute can be written. |
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RO | Read only: Read only. Writes have no effect. |
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WO | Write only: If a register or bit is |
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WC | Write One to Clear: writing a one clears the value. Writing a zero has no effect |
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WAC | Write Anything to Clear: writing anything clears the value. |
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RC | Read to Clear: Contents is cleared after the read. Writes have no effect. |
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LL | Latch Low: Clear on read of register. |
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LH | Latch High: Clear on read of register. |
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SC | |
| effect. Contents can be read. |
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SS | |
| effect. Contents can be read. |
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RO/LH | Read Only, Latch High: Bits with this attribute will stay high until the bit is read. After |
| it is read, the bit will either remain high if the high condition remains, or will go low if |
| the high condition has been removed. If the bit has not been read, the bit will remain |
| high regardless of a change to the high condition. This mode is used in some Ethernet |
| PHY registers. |
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NASR | Not Affected by Software Reset. The state of NASR bits do not change on assertion |
| of a software reset. |
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RESERVED | Reserved Field: Reserved fields must be written with zeros to ensure future |
| compatibility. The value of reserved bits is not guaranteed on a read. |
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Many of these register bit notations can be combined. Some examples of this are shown below:
R/W: Can be written. Will return current setting on a read.
R/WAC: Will return current setting on a read. Writing anything clears the bit.
SMSC LAN9312 | 19 | Revision 1.4 |
| DATASHEET |
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