GO Command

8)Gives the TX GO command by writing the address of the first available list to the CH_PARM register

9)Writes a 1 to the GO bit of the HOST_CMD register, with the transmit chan- nel selected

This assumes the transmit interrupt threshold has been initialized. If not, write to HOST_CMD with the Ld_Thr bit set and the threshold value in the Ack_Count field.

For frame transmission, the driver first allocates memory for the transmit lists and buffers and octet (byte) aligns the transmit lists. Next, the driver links the list by having the forward pointer point to next available list. The forward pointer must be 0 in the last list used. Next, the driver initialize the CSTAT fields in the lists.

After this system of linked lists is created, the driver writes the address of the first list to the CH_PARM register. This tells ThunderLAN where the first linked list is. After this, a Tx GO command is given. ThunderLAN initiates the DMA of data into its internal FIFO and then ThunderLAN transfers at least 64-bytes, or the value given in the Acommit register, into its internal FIFO before starting frame transmission.

When ThunderLAN finishes transferring data into its internal FIFO, it sets the Frm_Cmp bit in the CSTAT field. (ThunderLAN sets the bit when the frame is transmitted to the FIFO, not when network transmission is complete). The driv- er looks into the Frm_Cmp bit to verify frame transfer. Depending on the value loaded into the Ld_Thr bit in HOST_CMD, a Tx EOF interrupt is given to the host. The driver then needs to acknowledge the number of frames it has sent to ThunderLAN. This is important, as ThunderLAN and the driver have to agree on the number of frames sent. If there is a discrepancy, and the host ac- knowledges more frames than ThunderLAN has sent, ThunderLAN assumes that a serious hardware error has occurred and an adapter check 06h AckErr will follow.

When the driver determines the Frm_Cmp bit is set, it frees up the list and buff- er for the next transmit list. When the driver wishes to transmit a frame, it sets up the Tx list to point to the buffer that holds the frame. It writes a forward point- er of 0 to make this the last list in the chain. Finally, the previous list's forward pointer must be changed to write to the beginning of this list. ThunderLAN then transmits this frame as it goes down the linked lists. There are situations when ThunderLAN has completed transmitting the previous list and has seen the 0 forward pointer, in which case it closes the Tx channel and gives a Tx EOC interrupt. The driver then acknowledges the EOC and resumes transmitting by issuing another Tx GO command.

Transmitting and Receiving Frames

6-7

Page 101 Page 103
Page 102
Image 102
Texas Instruments TNETE211, TNETE110A, TNETE100A manual GO Command
Page 101 Page 103

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.
Top Page Image Contents