GO Command

forward pointer point to the next available list. The last list should have a for- ward pointer of 0. You must then initialize the CSTAT fields in the lists.

Opening a receive channel works in much the same way as opening a transmit channel. You must first write the address of the beginning of the list chain to CH_PARM and then give the receive open channel (Rx GO) command. ThunderLAN DMAs the data from its internal FIFO to the receive buffer pointed to in the list structure.

ThunderLAN writes the data count field with the data size when the frame is complete. The Frm_Cmp bit in the receive CSTAT complete field is set when the receive data is completely DMAed into the receive buffer. ThunderLAN then gives the host an Rx EOF interrupt. The driver looks at the Frm_Cmp bit to determine when the receive frame is complete and acknowledges the inter- rupt. The driver frees up the buffer for a new frame.

The driver makes the old list's forward pointer equal to 0. The previous list's forward pointer can be set up to point to this list. If done quickly, ThunderLAN always has a receive buffer to place frames in and the receive channel remains open. If ThunderLAN encounters the 0 forward pointer (meaning that it has filled the last buffer available to it), it gives the host an Rx EOC interrupt and stops the receive channel.

Implementing continuous receive reduces the possibility of losing frames due to not having receive buffers. In continuous receive, the driver acknowledges Rx EOF interrupts as each frame is delivered to the host. The driver manages the receive lists and buffers so that ThunderLAN always has a free buffer to place data in.

In case of an Rx EOC interrupt, the driver frees up buffers for the receive pro- cess, creates a system of linked lists, and restarts the receive channel by issu- ing an Rx GO command.

The Rx GO command is used to pass a receive list structure to ThunderLAN. ThunderLAN uses the list structure to DMA the received data from the network. There are two steps involved in issuing an Rx GO command:

-In the CH_PARM register, write the physical address of the beginning of the list structure. ThunderLAN uses this physical address to DMA data to host memory.

-In the HOST_CMD register, write the appropriate bits to start the channel. The Rx GO command writes to the GO bit and selects the transmit channel by writing to the Ch_Sel field. Set R/T to 1, indicating a receive command.

Transmitting and Receiving Frames

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Texas Instruments TNETE110A, TNETE211, TNETE100A manual GO Command
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TNETE110A, TNETE211, TNETE100A specifications

Texas Instruments has been a leader in developing innovative semiconductor solutions, and their Ethernet PHY (Physical Layer Transceiver) family, specifically the TNETE100A, TNETE211, and TNETE110A, exemplifies this commitment to excellence. These devices are designed to address the needs of a variety of applications, ranging from industrial automation to consumer electronics.

The TNETE100A is a highly versatile Ethernet PHY capable of supporting 10/100 Mbps Ethernet connectivity. One of its main features is the low power consumption, which makes it an ideal choice for battery-operated devices. It incorporates advanced power management technologies, ensuring that the device operates efficiently while maintaining high performance. The TNETE100A also supports Auto-Negotiation, allowing for seamless communication between devices at different speeds, thereby enhancing flexibility in network configurations.

Moving to the TNETE211, this device supports 10/100/1000 Mbps Ethernet, making it suitable for high-speed networking applications. This PHY integrates features such as Energy Efficient Ethernet (EEE), which reduces power consumption during low-traffic periods, aligning with the contemporary demand for energy efficiency in networking equipment. The TNETE211 is engineered with robust EMI (Electromagnetic Interference) performance and provides multiple interface options, making it a versatile choice for embedded systems and networking applications.

The TNETE110A stands out in the lineup as a sophisticated device that supports both Fast Ethernet and Gigabit Ethernet. This PHY utilizes advanced signal processing techniques to ensure superior link robustness and performance in noisy environments. Its features include an integrated transformer driver, which simplifies PCB design and allows for compact device layouts. Additionally, the TNETE110A is designed to be fully compliant with Ethernet standards, ensuring reliable interoperability with other network components.

All three PHYs leverage Texas Instruments' expertise in integrated circuit design, resulting in low jitter and high signal integrity, essential for modern communication standards. They are optimized for a wide range of temperatures, making them suitable for harsh industrial applications. With built-in diagnostic capabilities, these devices also enable efficient fault detection and troubleshooting in network infrastructures.

In summary, the Texas Instruments TNETE100A, TNETE211, and TNETE110A are exemplary Ethernet PHY devices, each tailored to meet specific networking needs while adhering to stringent efficiency and performance criteria. Their advanced features, technologies, and reliability make them pivotal components in today's fast-paced digital landscape.
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