CS8900A Datasheet, PDF(78/128 Page) Cirrus Logic – Crystal LAN ™ ISA Ethernet Controller

English

English German Russian Spanish Italian Polish Chinese Japanese Korean French Portuguese	Language :

CS8900A Datasheet, PDF (78/128 Pages) Cirrus Logic – Crystal LAN ™ ISA Ethernet Controller

◁

CS8900A

Crystal LANâ¢ ISA Ethernet Controller

host memory. Preceding the frame data are the

contents of the RxStatus register (PacketPage

base + 0400h) and the RxLength register (Pack-

etPage base + 0402h).

For a more detailed description of receive, see

Section 5.2 on page 79.

4.10.10 Accessing Internal Registers

To access any of the CS8900Aâs internal registers

in I/O Mode, the host must first setup the Pack-

etPage Pointer. It does this by writing the Pack-

etPage address of the target register to the

PacketPage Pointer Port (I/O base + 000Ah). The

contents of the target register is then mapped into

the PacketPage Data Port (I/O base + 000Ch).

If the host needs to access a sequential block of reg-

isters, the MSB of the PacketPage address of the

first word to be accessed should be set to "1". The

PacketPage Pointer will then move to the next word

location automatically, eliminating the need to set-

up the PacketPage Pointer between successive ac-

cesses (see Figure 18).

4.10.11 Polling the CS8900A in I/O Mode

If interrupts are not used, the host can poll the

CS8900A to check if receive frames are present

and if memory space is available for transmit.

CIRRUS LOGIC PRODUCT DATA SHEET

DS271PP3

▷