
QM8 board for the Amiga computer
|
|
These instructions are for those Pangolin users with the older QM8 board, used with the Commodore Amiga 3000 computer.
Description
The QM8 performs the same function as the Amiga custom chip
called "Paula".
Disk operations and the
standard left and right audio outputs function normally with a QM8
installed -- there is no difference over Paula operation.
The QM8 adds four RCA
jacks which provide the four separate audio channels (before being
mixed into two stereo channels). The signal at these jacks is
bipolar DC, -5 to +5 volts. This is intended for use with laser
scanner amplifiers, but can be used for other DC control voltage
applications.
Installation
-
Open the Amiga 3000. Locate expansion slot #1, the bottommost
slot on the four-slot vertical daughterboard. Locate the Paula
48-pin chip, in the middle of the left side, marked
"8364" on the chip.
-
Install the QM8 in expansion slot #1. This slot is used so the
cable does not have to snake around other boards. Note that the
QM8 does not plug into the slot on the daughterboard, but
instead mounts directly to the metal plate which covers the slot
rear opening.
-
Note index mark on short side of Paula
chip, closer to the
rear of the A3000. The cable will match this orientation (pins 1
and 48 are at the end with the index mark).
-
Carefully remove the
Paula chip, taking care not to bend pins or damage the board
underneath the chip. Set Paula aside for use if the QM8 is later
removed.
-
Install the cable into the Paula socket with the
correct orientation.
-
Locate R404 and R405 on the board, in the group of seven
resistors (see photo below, where the seven resistors are marked
by seven blue lines). The resistors will probably be
covering the R404 and R405 labels, so you should identify these
resistors by location only. They will have a
brown-black-black-gold color code.
-
Attach the CAEC clip lead to the right side of R404, the third
resistor in the group (the first one being towards the rear).
-
Attach the HIRAM clip lead to the right side of R405, the fourth
resistor in the group.
-
Check your work, then close the Amiga.
The RCA jacks on the QM8 are unlabelled. The outputs (X, Y, Z and
color) come out of different jacks depending on your QM8 and the
Pangolin program you are using. You should experiment to find the
correct signals for your QM and particular program. If you use
different programs, you may need to switch cables.
Location of CAEC, HIRAM and Paula
|