Cirrus Logic AN83 - Manual (Page 50)

AN83
50 AN83REV3
PacketPage Memory Base
Bits 15-4 12 MSB of Memory Base Address - The twelve most significant bits of the 24-bit address
locating the base of the CS8900A’s PacketPage memory. The lower twelve bits are as-
sumed to be 0. Default is 0.
Bits 3-0 Reserved (set to 0)
Boot PROM Memory Base
Bits 15-4 12 MSB of Memory Base Address - The twelve most significant bits of the 24-bit address
locating the base of the CS8900A’s PacketPage memory. The lower twelve bits are as-
sumed to be 0. Default is 0.
Bits 3-0 Reserved (set to 0)
Boot PROM Mask
Bits 15-4 12 MSB of Boot PROM Addr. Mask - Twelve-bit Boot PROM address mask. The lower
twelve bits are assumed to be 0. Refer to the CS8900A Data Sheet for a discussion of the
Boot PROM mask. Default is 0.
Bits 3-0 Reserved (set to 0)
Transmission Control
Bit 15 Full Duplex Mode - Specifies full-duplex or half-duplex mode for transmission. Default is
0 (half-duplex operation).
Bits 14-7 Reserved (set to 0)
Bit 6 Ignore Missing Media (IMM) - Specifies device driver’s behavior if a cable or AUI is not
connected during driver initialization. The driver’s behavior can be summarized by the fol-
lowing four cases. Default is 0.
CASE 1 (IMM = 0, media autodetect selected, cable not connected)
Driver disables TX/RX and unloads if dynamic load/unload is supported by OS.
CASE 2 (IMM = 0, media type specified
[10B-T,AUI,10B-2], cable not connected)
Driver disables TX/RX and unloads if dynamic load/unload is supported by OS.
CASE 3 (IMM = 1, media autodetect selected, cable not connected)
Driver disables TX/RX and unloads if dynamic load/unload is supported by OS.
CASE 4 (IMM = 1, media type specified
[10B-T,AUI,10B-2], cable not connected)
Driver remains resident, reports "Media type
XXXXX not detected", and functions normal-
ly if/when the specified cable type is connected.
Bits 5-0 Reserved (set to 0)