Table 4.8

Additional Interface Signals (Cont.)

 

 

 

 

Name

Pin No.

Type

Description

 

 

 

 

MAC/_

53

T/S

Memory Access Control. This pin can be programmed to indicate

TESTOUT

 

 

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.

 

 

 

 

SCSI Bus Interface Signals

4-11

Page 73
Image 73
LSI 53C810A technical manual Mac