ES1938

ESS Technology, Inc. DESCRIPTION The ES1938 PCI AudioDrive® solution implements a single-chip PCI audio solution, providing high-quality audio processing while maintaining full legacy DOS game compatibility. With a dynamic range over 80 dB, the ES1938 complies with the Microsoft® PC 98 / PC 99 specifications and meets WHQL audio requirements. The ES1938 forms a complete audio subsystem on a single chip for motherboard platforms. The ES1938 incorporates a microcontroller, ESFMTM music synthesizer, 16-bit stereo wave ADC and DAC, 16-bit stereo music DAC, MPU-401 UART mode serial port, dual game port, hardware master volume control, a serial port interface to external wavetable music synthesizer, DMA control logic with FIFO, and PCI bus interface logic. There are three stereo inputs (typically, line-in, CD audio, and auxiliary line) and a mono microphone input. The ES1938 provides a serial EEPROM interface for ease of programming the Subsystem ID and Subsystem Vendor ID. The ES1938 integrates the ESS Technology field-proven hardware design for DOS game compatibility with hardware FM synthesis (ESFM synthesis) and three methods for legacy audio control interface: PC/PCI, Distributed DMA, and Transparent DMA. Transparent DMA requires no sideband signals from PC core logic chipsets in addition to the standard PCI 2.2 bus. Transparent DMA (TDMA) is compatible with the Intel®Pentium®, Pentium II®, and Celeron™ chipsets, as well as standard PCI add-in cards. The ES1938 can record, com...