Speaker Interface - DIGITAL-LOGIC MICROSPACE PC/104 Technical User's Manual

DIGITAL-LOGIC AG
Floppy Disk Interface Connector
FD34: FD26:
Pin Pin
2
4 ---
6 ---
8 2
10
12 4
14
16 10
18 12
20 14
22 16
24 18
26 20
28 22
30 24
32 26
34 6
1-33 25,23,21,19,17
1,3,5
4.3.6

Speaker interface

One of the board's CPU device provides the logic for a PC compatible speaker port. The speaker logic
signal is buffered by a transistor amplifier, and provides approximately 0,1 watt of audio power to an
external 8 ohm speaker. Connect the speaker between VCC and speakeroutput, to have no quiescient
current.
Signal Name
-RPM/-RWC
(Not used)
(Not used)
-IDX
-MO1
-DS2
-DS1
-M02
-DIRC
-STEP
-WD
-WE
-TRKO
-WP
-RDD
-HS
-DCHG
GND
VCC
22
MSM486V Manual V3.22
Function
Speed/Precomp (option)
Index Pulse
Motor On 1
Drive Select 2
Drive Select 1
Motor On 2
Direction Select
Step
Write Data
Write Enable
Track 0
Write Protect
Read Data
Head Select
Disk Change
Signal grounds
+5 Volt
in/out
out
in
out
out
out
out
out
out
out
out
in
in
in
out
in