Tektronix 2230 Service Manual

data at that address is F4, the following error message is
displayed on the crt:
ACQ_MEM : even @ 4008 FO < > F4
Maintenance—2230 Service
PRC. This test checks the Post Record Counter write
and the B-TRIG read circuitry. Twenty four unique
patterns are written into the Post Record Counter (U4115
U4116 and U4117) and read through the B Delay Timer
(U4123 U4124).
The B Delay Timer is clocked by a write to the Time
Base Divider register (U4114 pin 8 through U4107 pin 4),
the inactive B-GATE (U4121B pin 11), and the TRGD
(U4121B pin 13) signals.
Push the SELECT C1/C2 switch to stop pattern
changes. The test loops using the pattern for the first
error found. All patterns used are shown in Table 6-15.
NOTE
If rec-clk is active unpredictable results occur.
If an error is found, the value read back and the value
expected are displayed on the crt:
PRC : read-back <actual> < > <expected>
For example, if the value read back is 008 and the
value expected is OOF the following error message is
displayed on the crt:
PRC : read-back 008 < > OOf
If the oscilloscope is operating in extended diagnostics
mode, the error display is expanded to include all errors,
not just the first error. Also, in extended diagnostics mode
the RS-232-C Option can be used to send the error
reports to a terminal or computer. This enables analysis of
the data for pattern recognition. For example, if bit 5
(U4116 pin 15) is shorted to ground all patterns where bit
5 should be a one will have a zero in bit position 5 and
therefore fail.
HS_ACQ. This test checks the High Speed Acquisition
using a 260 byte acquisition at the fastest record speed
(record clock = convert clock =* 20 MHz = 50 ns per
byte) sampling the Diagnostic Code generators.
Table 6-15
PRC Test Patterns
Binary
A ll A0
Hexadecimal
A0
0000 0000 0001
001
0000 0000 0011
003
0000 0000 0111
007
0000 0000 1111
OOF
0000 0001 1111
01F
0000 0011 1111
03F
0000 0111 1111
07 F
0000 1111 1111
OFF
0001 1111 1111
IFF
0011 1111 1111
3FF
0111 1111 1111
7FF
1111 1111 1111
FFF
1111 1111 1110
FFE
1111 1111 1100
FFC
1111 1111 1000
FF8
1111 1111 0000
FF0
1111 1110 0000
FE0
1111 1100 0000
FC0
1111 1000 0000
F80
1111 0000 0000
F00
1110 0000 0000
E00
1100 0000 0000
COO
1000 0000 0000 800
0000 0000 0000 000
NOTE
This is the only test which absolutely origins the fill;
others only test the slope of the fill.
Synchronous to NMI the Acquisition Address Counter
(U3423, U3424, and U3425) is loaded with 0x1000 - 0x96
(Ox0F6A) and the Post Record Counter (U4115, U4116,
6-24

Tektronix 2230 Specifications

General

Brand	Tektronix
Model	2230
Category	Test Equipment
Language	English