6-12 User’s Manual6.4.7 Parallel Port Operation ModeThe parallel port supports four operation modes:• Standard and Bidirectional• Extended Capabilities Port(ECP)• Standard and Unidirectional• Enhanced Parallel Port(EPP)ECP or Extended Capabilities Port supports a 16-byte FIFO (first in, firstout) which can be accessed by host DMA cycles and PIO cycles. ECPboosts I/O bandwidth to meet the demands of high-performanceperipherals. EPP or Enhanced Parallel Port is a parallel port interface thatgreatly improves performance for bi-directional block-mode data transfers.EPP provides greater throughput by supporting faster transfer times and amechanism that allows the host to address peripheral device registersdirectly.The default setting is [Standard and Bidirectional].If you set EPP as the parallel port operation mode, do not use3BCh as the parallel port base address; otherwise, I/O conflictsmay occur.ECP DMA ChannelSet the ECP DMA Channel parameter if you set the Parallel Port OperationMode to [Enhanced Capabilities Port(ECP)]. The defaultvalue, with ECP selected, is [0].
