For examples:
ATZ

(38500 bps and up), the PC may not be fast enough and data may become lost. In this case, a UART with data buffer is need such as NS16550A.

NVRAM

NVRAM(Non-Volatile RAM) is a device to store the DCE configuration. Upon powering-up, the modem defaults to the configuration specified in the NVRAM or to the factory default (if the NVRAM was not installed). DCE configuration can be changed and stored by DTE in the NVRAM by first setting up the current configuration and then sending an AT command &Wn. The active profile will be lost if reset commands were issued or the modem is not powered.

Resets and then configures the modem to NVRAM user profile 0.

AT&F S0=1 &W1 &Y1 &F configures the modem to factory default &S0=1 configure the modem to answer after one ring

&W1 saves the active configuration to profile 1 &Y1 Configure the modem to use NVRAM user profile 1 as the power-up defaults.

AT COMMAND SET AND S-REGISTER

The modem (DCE) operates in one of two states: command or on-line. In each state, data and commands (including DCE response) are both transfer through the UART. In command state, the host (DTE) communicates to the modem through AT (stands for attention) commands and S-registers. AT command set is the industry standard used to control the modem in command state. S-registers are internal modem registers that DTE can access. AT command set extended by each modem manufacture for the control of more modem functions and capabilities. For more information, please refer to the Chapter 5 AT Commands.

INITIALIZATION STRINGS

An Initialization string is a series of specific commands that prepares a modem to operate with communications software. Consult with your

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Jaton V.90 user manual Nvram

V.90 specifications

The Jaton V.90 modem is a classic example of 56K technology that revolutionized dial-up internet connections in the late 1990s. As one of the early models supporting the V.90 standard, this modem enabled users to experience faster internet speeds compared to its predecessors. The V.90 protocol allowed for a maximum download speed of 56 Kbps, offering significant improvements over the previous V.34 modem, which capped out at 33.6 Kbps.

One of the standout features of the Jaton V.90 is its ability to adapt to different line conditions, ensuring optimal performance regardless of the quality of the telephone line. The V.90 standard provided a retransmission mechanism that allowed data to be resent if errors occurred during transmission, improving reliability and reducing the likelihood of dropped connections.

The modem incorporates technologies such as error correction and data compression. With built-in error correction protocols like V.42 and MNP, the Jaton V.90 can detect and correct common transmission errors, which is vital in maintaining a stable connection. The data compression technology, which uses MNP Class 5, enhances throughput by compressing data before transmission. As a result, users could effectively increase their upload speeds and minimize latency, creating a more seamless browsing experience.

The hardware features of the Jaton V.90 modem typically include a standard RJ-11 telephone connector, which makes it easy to connect to existing phone lines. The modem may come with both internal and external configurations, allowing flexibility depending on user preferences and system requirements. The external version often features indicator LEDs that provide real-time feedback on connection status, data transfer activity, and power status.

Compatibility is another crucial aspect of the Jaton V.90 modem. Operating with a variety of systems, it was designed to work with Windows, Mac OS, and other operating environments, making it accessible for a wide range of users. Additionally, the modem generally supports various software applications for easy configuration and management.

Ultimately, the Jaton V.90 modem played a pivotal role in facilitating internet access during a transformative period, laying the groundwork for future high-speed connections. While modern broadband solutions have since eclipsed dial-up speeds, the legacy of the Jaton V.90 as a reliable and innovative piece of technology remains significant in the history of internet connectivity.