Tektronix TG8000 Service Manual

Mainframe troubleshooting
Slot diagnosti
cs error codes. The following table lists the error codes that may
appear when running the slot diagnostics using a GPS7 module:
Table 2-3: Slot diagnostics e rror codes
Error
code Description Tro ub lesho oting actions
CS6/Data bus test
0x1
1
Read-back of both bytes fails on every
write/read
Indicates that there is an issue with the address bus, data bus, CS6_N,
WAIT_N, any
of the write/read control signals (RD_N, R_W_N, WEN0,
WEN1) or CKIO (54 MHz bus clock). The HW uses all available
control signals when decoding the CPU accesses in order to test
connectiv
ity/functionality.
Note that MWAIT* should pulse low during these tests. The HW waits 24
CPU clocks before sending the data on reads in order to test the WAIT_N
signal (C
PU accesses to GP S7 are normally wait-stated by the GPS7CPLD
to ~32 CPU clocks). If WAIT_N is not connected to the slot, the read cycles
will end after the default time of 1 2 clocks and the data will be received
as all zer
os.
Note that this test may fail if there is an address bus problem, so the
CS4/Address bus test below may help isolate the issue. But, the address
bus test
will fail if there is an i ssue with the data bus, so the results of both
tests must be carefully weighed. Probing the address and data signals
along with the control signals while the two tests run will show if there is a
stuck a
t 0 or stuck at 1 issue on a particular bit.
0x1A
1
Read-b
ack of address c800_001C failed
Indica
tes that one or more bus control signals are stuck low. Check the
console to determine the value read back to determine which signal has
an issue. Also, use the test points on the GPS7 module to verify that the
contr
ol signals toggle during the IO slot tests. (See Figure 2-3.)
0x2
1
Read-
back of upper byte is correct, but
lower byte fails on every w rite/read
Only t
he lower byte of the data bus is failing which means that there is
an issue with WEN0 or slot data [7:0]. The address bus and other control
signals are most likely OK. If some o f the write/read combinations work,
then
the issue is with slot data[7:0] (not WEN0).
0x3
1
Read
-back of lower byte is correct, but
upper byte fails on every write/read
Only
the upper byte of the data bus is failing which means that there is an
issue with WEN1 or slot data [15:8]. The address bus and other control
signals are most likely OK. If some o f the write/read combinations work,
the
n the issue is with slot data[15:8] (not WEN1).
0x4
1
Wa
lking zeros test failed
This indicates that there is a data bus short or open.
0x5
1
Wa
lking ones test failed
This indicates that there is a data bus short or open.
C
S4/Data bus test
0x6,
1
0
x7
1
0x6 indicates that the address walking
z
eros test failed
0x7 indicates that the address walking
ones address test failed
I
f error code 0x8 is also present, then the CS4* signal is likely open or
shorted. If error code 0x8 is not present, then there is a short or open on
one or more address lines. Note that the HW registers the address lines for
writes to CS4* space - 0xC800:0012 contains AD[16:1], and 0xC800:0014
contains AD[25:17].
0x8
1
The address walking zeros and ones
tests failed completely
This likely means that the CS4* signal is open or shorted. This could also
mean that chip select 6 (CS6x*) is stuck low.
TG8000 Multiformat Test Signal Generator Service Manual 2–13

Tektronix TG8000 Specifications

General

Brand	Tektronix
Model	TG8000
Category	Portable Generator
Language	English