LSI 53C810A User Manual
Page 73
SCSI Bus Interface Signals
4-11
MAC/_
TESTOUT
53
T/S
Memory Access Control. This pin can be programmed to indicate
local or system memory accesses (non-PCI applications). It is also
used to test the connectivity of the LSI53C810A signals using an “AND
tree” scheme. The MAC/_TESTOUT pin is only driven as the Test Out
function when the TESTIN/ pin is driven LOW.
IRQ/
47
O
Interrupt. This signal, when asserted LOW, indicates that an
interrupting condition has occurred and that service is required from the
host CPU. The output drive of this pin is programmed as either open
drain with an internal weak pull-up or, optionally, as a totem pole driver.
Refer to the description of
DMA Control (DCNTL)
register, bit 3, for
additional information.
Table 4.8
Additional Interface Signals (Cont.)
Name
Pin No. Type Description