NCT6627UD Nuvoton Technology Corporation of America, NCT6627UD Datasheet - Page 145

• Manufacturer Part Number: NCT6627UD
• Manufacturer: Nuvoton Technology Corporation of America

Specifications of NCT6627UD

• Lead Free Status / Rohs Status: Supplier Unconfirmed

DMA transfers are always to or from the ecpDFifo, tFifo, or Cfifo. DMA uses the standard PC DMA services. The
ECP requests DMA transfers from the host by activating the PDRQ pin. The DMA empties or fills the FIFO using
the appropriate direction and mode. When the terminal count in the DMA controller is reached, an interrupt is
generated, and serviceIntr is asserted, which will disable the DMA.
The ECP and parallel port FIFOs can also be operated using interrupt-driven, programmed I/O. Programmed I/O
transfers are
The host must set dmaEn and serviceIntr to 0 and also must set the direction and state accordingly in the
programmed I/O transfers.
The ECP requests programmed I/O transfers from the host by activating the IRQ pin. The programmed I/O
empties or fills the FIFO using the appropriate direction and mode.
11.3.13 DMA Transfers
11.3.14 Programmed I/O (NON-DMA) Mode
1. To the ecpDFifo at 400H and ecpAFifo at 000H
2. From the ecpDFifo located at 400H
3. To / from the tFifo at 400H.
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W83627UHG/NCT6627UD
Publication Release Date: October 26, 2010
Revision 1.7