Tektronix TDS6404, Service Manual

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Troubleshooting
TDS6000 Series Service Manual
6- 69
Table 6- 10: Beep codes (Bali) (Cont.)
Beeps Description
8 Display memory R/W error
9 ROM checksum error (not used)
10 CMOS shutdown register test error
11 Invalid BIOS (for example, POST module not found, etc.)
BIOS Beep Codes (Radisys NLX)
When the NLX board powers-on a number of the BIOS checkpoints generate an
audible ’beep’ code on failure using the standard PC speaker (also routed
through the board audio system). The beep codes are made up of up to 4 groups
of short beeps and are listed in Table 6--11.
If your instrument does not contain a speaker, attach a speaker to the display-
adapter board square pins to hear the codes.
Table 6- 11: Beep codes (Radisys)
Check-
point code
Error message Beep code
16h BIOS ROM checksum 1-2-2-3
20h Test DRAM refresh 1-3-1-1
22h Test 8742 keyboard controller 1-3-1-3
2Ch Test 512 Kb base address lines 1-3-4-1
2Eh Test low byte of 512 Kb base memory 1-3-4-3
46h Check ROM copyright notice 2-1-2-3
58h Test for unexpected interrupts 2-2-3-1
98h Search for option ROMs (beep for bad checksum) 1-2
B4h One beep before boot 1
Dip Switch Controls
Dip switch is used to direct program flow during power on self test (POST). A
switch set to ON is closed and presents a low state (0 V) to the switch buffer.
This is the default switch position. A switch set to OFF is open and presents a
high state (3.3 V) to the switch buffer. This is the ’set’ position. Table 6--12
describes the switch functions.