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Atari Technical Bulletin
Number: TT30-0004
Date: March 27, 1992
Page 1 of 3


Product(s) Affected:	TT030
Model:				All
Type of ATB:			As Needed
ECO #: 				1434

Reason for ATB:

To correct boot up problems on C301763-001 REV D FAB boards after ATB TT30-0002 or ECO 1425 was applied.


Notes:

After installing the fix described in ATB TT30-0002 or ECO 1425 several TT030 systems using the C301763-001 REV D FAB main board exhibited problems booting when a TT RAM board is installed. The following procedure will correct those problems. The problem only pertains to the C301763-001 REV D FAB.


Symptoms of Problem:

During boot-up the system will fail with X's when TT RAM test is performed or bomb on Boot-up if TT RAM is installed.


Solution:

1.	Remove the top cover.

2.	Remove the VME Card Guide.

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Atari Technical Bulletin
Number: TT30-0004
Date: March 27, 1992
Page 2 of 3


3.	If ECO 1425 or ATB TT30-0002 is not installed, skip to step 4. If the first oscillator modification is installed, ECO 1425 or ATB TT30-0002, remove the wire from the left side of R888 and R997. See Figure 1.

4.	Lift pins 3 and 17 of U210 so the pins are clear of the pads on the main PCB. See Figure 2.

5.	Connect a wire from the right side of R997 to U210 pin 17. See Figure 2.

6.	Connect a wire from U210 pin 3 to the left side of R888. See Figure 2.

7.	Insulate the connection at R888 with Heatshrink Tubing to guard against any possible shorts. See Figure 2.

8.	Re-assemble the unit.

Heatshrink Tubing

Wire From R997

Left Side of R888

U111

R997

R888

U110

U114

U112

C115

C599

C215

R899

R951

VME
Backplane

U206

U900

UA00

Figure 1

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Atari Technical Bulletin
Number: TT30-0004
Date: March 27, 1992
Page 3 of 3

C911

Wire From U210 Pin 17

Heatshrink Tubing

U210

U203

Wire From U210 Pin 3

U204

Left Side of R888

U111

R997

R888

U110

U114

U112

C115

C599

C215

R899

R951

VME
Backplane

U206

U900

UA00

Figure 2