---
layout: page
title: "EKBAD0: 11/70 MEMORY MANAGEMENT DIAGNOSTIC (PART 1)"
permalink: /disks/dec/rl02k/xxdp/ekbad0/
---

EKBAD0: 11/70 CPU DIAGNOSTIC (PART 1)
-------------------------------------

From the
[PDP-11 Diagnostic Handbook (1988)](http://archive.pcjs.org/pubs/dec/pdp11/diags/PDP11_DiagnosticHandbook_1988.pdf),
p. 1-6:

	11/70 CPU DIAGNOSTIC PART 1
	
	ABSTRACT:
	
	    This diagnostic is the first part of the 11/70 CPU, it designed to detect and
	    report logic faults in the CPU. Any fault detected in this program causes the
	    program to "HALT". After this, run the second part of the CPU test, EKBBF0.
	
	OPERATING PROCEDURES:
	        Set the switch register by <CONTROL P> (RD console)
	    CON = xxxxxxWZ
	        (W = deposit xxxxxx into console switch register)
	        (R = read and type console switch settings)
	        (Z = switch console terminal back to program)
	
	    .R EKBAD0
	
	SWITCH SETTINGS
	    SW15 = 1 halt on error
	    SW14 = 1 loop on test
	    SW13 = 1 inhibit error typeouts
	    SW12 = 1 inhibit T-bit trapping
	    SW11 = 1 inhibit iterations
	    SW10 = 1 ring bell on error
	    SW09 = 1 loop on error
	    SW08 = 1 loop on test in SWR <07:00>
	    SW07 = 1 not used
	    SW06 = 1 skip bus request 6 test
	    SW05 = 1 skip bus request 5 test
	    SW04 = 1 skip bus request 4 test
	    SW00 = 1 skip operator intervention testing

The closest we have to a source code listing of the EKBAD0 diagnostic comes from some
[scanned microfiche](http://archive.pcjs.org/pubs/dec/pdp11/diags/AH-7963D-MC_CEKBAD0_1170_CPU_1_May80.pdf)
on [bitsavers.org](http://bitsavers.trailing-edge.com/pdf/dec/pdp11/microfiche/ftp.j-hoppe.de/bw/gh/) for:

	PRODUCT CODE: AC-7962D-MC
	PRODUCT NAME: CEKBAD0 11/70 CPU #1
	DATE CREATED: MAY, 1980
	MAINTAINER:   DIAGNOSTIC ENGINEERING