DS3134 datasheet(132/203 Pages) DALLAS

tên linh kiện	DS3134

Giải thích chi tiết về linh kiện	Chateau Channelized T1 And E1 And HDLC Controller

PDF	203 Pages

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nhà sản xuất	DALLAS [Dallas Semiconductor]

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DS3134

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The Transmit DMA will read from the Transmit Pending Queue Descriptor circular queue which data

buffers and their associated descriptors are ready for transmission. To keep track of the addresses of the

circular queue in the Transmit Pending Queue, there are a set of internal addresses within the device that

are accessed by both the Host and the DMA. On initialization, the Host will configure all of the registers

shown in Table 8.2.3A. After initialization, the DMA will only write to (i.e. change) the read pointers

and the Host will only write to the write pointers.

Empty Case

The Transmit Pending Queue is considered empty when the read and write pointers are identical.

Transmit Pending Queue Empty State

empty descriptor

read pointer >

empty descriptor

< write pointer

empty descriptor

Full Case

The Transmit Pending Queue is considered full when the read pointer is ahead of the write pointer by one

descriptor. Hence, one descriptor must always remain empty.

Transmit Pending Queue Full State

valid descriptor

empty descriptor

< write pointer

read pointer >

valid descriptor

DS3134 bảng dữ liệu(PDF) 132 Page - Dallas Semiconductor