Yay, partial success!

[Paul Williams]

gordonjcp at gjcp.net wrote:
> 
> SLU in, D3 is on.  SLU out, D3 *and* D4 is on.  But
> according to the manual (and the dead tree copy I now have is the same) D3
> is the SLU, D4 is the memory.  A site I now can't find had a description
> of the status LEDs that said that D3 was memory, and D4 was the SLU, but
> since *everything else* said it was the other way round I didn't believe
> it.

A later version of the manual has corrected this section.

EK-KDJ1A-UG-002, "KDJ11-A CPU Module User's Guide"

2.3 DIAGNOSTIC LEDS
The module has four LEDs that monitor the status of the module. The LEDs 
are designated as D1 through D4 and are located on the edge of the 
module, as shown in Figure 2-1. The D1 LED is turned on only when the 
module is operating in the micro-ODT mode. LEDs D2-D4 are used during 
the power-up sequence. These LEDs are turned on at the beginning of the 
sequence and are turned off upon the successful pass of the diagnostic. 
Each LED monitors a primary function of the module operation, as 
described in Table 2-4. When troubleshooting the system, the LEDs 
indicate the most probable failure, as described in Table 2-5.

Table 2-4  LED Functions
-------------------------------------------------------------------
LED on  Test Conditions
-------------------------------------------------------------------
D1      Micro-ODT is entered.

D2      Module could not do a write and read transaction to the CPU
         error register. Indicates the microcode is not running.

D3      Module attempted to read location 0 and timed out or attempted
         to read location 17 777 700 and did not time out. Indicates the
         memory system is not responding.

D4      Module attempted to read location 17 777 560 and timed out.
         Indicates SLU is not responding.
-------------------------------------------------------------------

Table 2-5  Probable System Failure
--------------------------------------
LEDs
D1   D2   D3   D4   Probable Failure
--------------------------------------
X    On   On   On   CPU module
X    Off  On   On   LSI-11 bus
X    On   Off  On   CPU module
X    Off  Off  On   SLU module
X    On   On   Off  CPU module
X    Off  On   Off  Memory module
X    On   Off  Off  CPU module
X    Off  Off  Off  Console terminal
--------------------------------------

-- 
Paul
Manx, a catalogue of online computer manuals: <http://vt100.net/manx/>