Motorola MVME1X7P - Manual (Page 148)

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VMEchip2
2
SNP These bits control the snoop signal lines on the local bus
when the DMAC is local bus master and it is not accessing
the command table. The snooping functions differ
according to processor type, as shown:
INTE This bit is used only in command chaining mode. It is only
modified when the DMAC loads the control register from
the control word in the command packet. When this bit in
the command packet is set, an interrupt is sent to the local
bus interrupter when the command in the packet has been
executed. The local bus is interrupted if the DMAC
interrupt is enabled.
DMAC Control Register 2 (bits 0-7)
This portion of the control register is loaded by the processor or the DMAC
when it loads the command word from the command packet. Because this
byte is loaded from the command packet in command chaining mode, the
descriptions here also apply to the control word in the command packet.
VME AM These bits define the address modifier codes the DMAC
drives on the VMEbus when it is bus master. During
non-block transfer cycles, bits 0-5 define the VMEbus
address modifiers. During block transfers, bits 2-5 define
SNP Requested Snoop Operation
14 13 MC68040 MC68060
0 0 Snoop disabled Snoop enabled
0 1 Source dirty, sink byte/word/longword Snoop disabled
1 0 Source dirty, invalidate line Snoop enabled
1 1 Snoop disabled (Reserved) Snoop disabled
ADR/SIZ $FFF40034 (8 bits of 32)
BIT 7 6 5 4 3 2 1 0
NAME BLK VME AM
OPER R/W R/W
RESET 0 PS 0 PS