Panasonic JB-3300 Technical Manual page 462

(1)
(2)
BOOT ROM READ check
READ of the BOOT ROM cannot be made.
(a)
(b)
(Cc)
(d)
BOOT ROM 2764 (IC) is faulty.
Address comparator 74LS682 (3F) is faulty.
Bus control 74LS245 (1E) is faulty.
There is not JPI-0O.
Basic operation of the controller
Is the internal operation of the controller normal after its power
has been turned on or it has been reset?
(a)
(b)
(c)
(d)
(e)
Check if the RD signal is output from MPU Z-80 (6E) Pin 39.
If the RD signal is not output;
o Check if the BUSRO signal from MPU 2-80 (6E) Pin 43 is on
the LOW level.
o Check if the INT signal from MPU Z-80 (6E) Pin 34 is on the
LOW level.
If the BUSRO signal is on the LOW level;
Oo NDC 840 LSI is faulty (FPU DMA).
Oo NDC 841 LSI is faulty (HOST I/F).
o 74LS02 (3D) is faulty.
If the INT signal is on the LOW level;
o NDC 840 LSI is faulty (FPU DMA).
o 74LS04 (4D) is faulty.
If the MPU Z-80 does not operate;
Oo Check if the IF CLK is normal? (2.5 MHz)
VII - 74