
FUJISTU LIMITED PRELIMINARY AN D CONFIDENTIAL
MB86295S<Coral-LP>
160
Specification Manual Rev1.1
Bit 6
IMODE (Interrupt Mode)
This b it controls how the external BURSTC/TRANSC signals operate. If set to “0b” they
are active high. Otherwise if set to “1b” they toggle at each change of state removing the
need for the host to read/write the status register to clear them down.
Note that when using the Burst Complete/Transfer Complete indications via the main
interrupt status register this field should always be “0b”.
Bit 7
XCOR (not Clear On Read)
If set to “0b” then the Burst Complete/Transfer Complete fields in the Burst Status register
are clear on read. Otherwise if set to “1b” they must be manually written.
BER (Burst Enable Register)
Register
address
HostBaseAddress + 8010H
Bit number
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5
4 3 2 1 0
Bit field name
Reserved
ABORT
*1
Reserved
EXTST
BEN
R/W
R0
W R0
RX
R0
R RW
Initial value
0
0 0
Don’t Care
0
0 0
*1 - Reserved
This register can be used to enable/pause/abort a transfer. It can also be used to monitor the state
of the external Burst Enable signal.
Bit 0
BEN (Burst ENable)
When set to “1b” a transfer is enabled. This bit will also become set if the STRT bit in the
BCR register is set. During a transfer this may be cleared to “0b” to pause/halt a transfer
at the next boundary between bursts. Setting it back to “1b” will re-enable the transfer
from the position it had reached.
Bit 1
EXTST (External Status)
Provided the state of the external Burst Enable signal.
Bit 16
ABORT
Under some circumstances clearing the BEN field may not halt a trans fer. This will
happen if the Burst Controller is waiting for an external PCI Master to take some action. In
this case writing “1b” to the ABORT field will cancel the transfer. The transfer will not be
able to be re-started.
BST (Burst STatus)
Register
address
HostBaseAddress + 8014H
Bit number
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5
4 3 2 1 0
Bit field name TC BC
Reserved
TCNT
R/W
R R
R0
R
Initial value
0 0
0
This register is used to monitor the state of the current transfer.
Bit 23 to 0
TCNT (Transfer CouNT)
Gives the current transfer count as a number of dwords remaining to be transferred.
Bit 30
BC (Burst Complete)
Indicates the state of a burst. Note that when in active high mode this field will remain
high following a burst unless it is cleared either by a clear on read or by writing 0 to it.