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TI486 Microprocessor - Al Kossow's Bitsavers

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Overview<br />

Table 4-2. Terminal Functions (Continued)<br />

NAME<br />

PIN<br />

NO.<br />

1/0 DESCRIPTION<br />

SUSP A4 I Suspend Request (active low). This is an input that requests the <strong>TI486</strong>0LC/E enter<br />

suspend mode. After recognizing SUSP active, the processor completes execution of<br />

the current instruction, any pending decoded instructions and associated bus cycles. In<br />

addition, the <strong>TI486</strong>0LC/E waits for the coprocessor to indicate a not busy status<br />

(BUSY = 1) before entering suspend mode and asserting suspend acknowledge<br />

(SUSPA).<br />

SUSP is internally connected to a pullup resistor to prevent it from floating active when<br />

left unconnected.<br />

SUSPA B4 0 Suspend Acknowledge (active low). This output indicates that the <strong>TI486</strong>0LC/E has<br />

entered the suspend mode as a result of SUSP assertion or execution of a HALT<br />

instruction.<br />

VCC A1 I 5-V Power Supply. <strong>Al</strong>l pins must be connected and used.<br />

A5<br />

A7<br />

A10<br />

A14<br />

C5<br />

C12<br />

012<br />

G2<br />

G3<br />

G12<br />

G14<br />

L12<br />

M3<br />

M7<br />

M13<br />

N4<br />

N7<br />

P2<br />

P8<br />

VSS A2 I Ground Pins. <strong>Al</strong>l pins must be connected and used.<br />

A6<br />

A9<br />

B1<br />

B5<br />

B11<br />

B14<br />

C11<br />

F2<br />

F3<br />

F14<br />

J2<br />

J3<br />

J12<br />

J13<br />

M4<br />

M8<br />

M10<br />

N3<br />

P6<br />

P14<br />

W/R B10 O/Z Write/Read. W/R is low during read cycles (data is read from memory or I/O) and is high<br />

during write bus cycles (data is written to memory or I/O).<br />

4-11

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