Rainbow Electronics AT75C220 - Manual (Page 36)

AT75C220
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hash matched frames. So all multicast frames can be
received by setting all bits in the hash register.
The CRC algorithm reduces the destination address to a 6-
bit index into a 64-bit hash register. If the equivalent bit in
the register is set, the frame will be matched depending on
whether the frame is multicast or unicast and the appropri-
ate match signals will be sent to the DMA block
If the copy all frames bit is set in the network configuration
register, the store frame pulse will always be sent to the
DMA block as soon as any destination address is received.
Register Map
Base Address MAC A: 0xFF034000
Base Address MAC B: 0xFF038000
Table 15. Ethernet MAC Register Map
Offset Register Name Description Access Reset Value
0x00 ETH_CTL Network Control Register Read/write 0x0
0x04 ETH_CFG Network Configuration Register Read/write 0x800
0x08 ETH_SR Network Status Register Read-only 0x4
0x0C ETH_TAR Transmit Address Register Read/write 0x0
0x10 ETH_TCR Transmit Control Register Read/write 0x0
0x14 ETH_TSR Transmit Status Register Read/write 0x18
0x18 ETH_RBQP Receive buffer queue pointer Read/write 0x0
0x1C – Reserved Read-only 0x0
0x20 ETH_RSR Receive Status Register Read/write 0x0
0x24 ETH_ISR Interrupt Status Register Read/write 0x0
0x28 ETH_IER Interrupt Enable Register Write-only –
0x2C ETH_IDR Interrupt Disable Register Write-only –
0x30 ETH_IMR Interrupt Mask Register Read-only 0xFFFF
0x34 ETH_MAN PHY Maintenance Register Read/write 0x0
Statistics Registers
0x40 ETH_FRA Frames transmitted OK Read/write 0x0
0x44 ETH_SCOL Single collision frames Read/write 0x0
0x48 ETH_MCOL Multiple collision frames Read/write 0x0
0x4C ETH_OK Frames received OK Read/write 0x0
0x50 ETH_SEQE Frame check sequence errors Read/write 0x0
0x54 ETH_ALE Alignment errors Read/write 0x0
0x58 ETH_DTE Deferred transmission frames Read/write 0x0
0x5C ETH_LCOL Late collisions Read/write 0x0
0x60 ETH_ECOL Excessive collisions Read/write 0x0
0x64 ETH_CSE Carrier sense errors Read/write 0x0
0x68 ETH_TUE Transmit underrun errors Read/write 0x0
0x6C ETH_CDE Code errors Read/write 0x0
0x70 ETH_ELR Excessive length errors Read/write 0x0