DIGITAL-LOGIC AG
PCCP5 Manual V2.3
25
Floppy Disk Interface Connector
FD34:
Pin
FD26:
Pin
Signal Name
Function
in/out
2
---
-RPM/-RWC
Speed/Precomp (option)
out
4
---
(Not used)
6
---
(Not used)
8
2
-IDX
Index Pulse
in
10
---
-MO1
Motor On 1
out
12
4
-DS2
Drive Select 2
out
14
---
-DS1
Drive Select 1
out
16
10
-M02
Motor On 2
out
18
12
-DIRC
Direction Select
out
20
14
-STEP
Step
out
22
16
-WD
Write Data
out
24
18
-WE
Write Enable
out
26
20
-TRKO
Track 0
in
28
22
-WP
Write Protect
in
30
24
-RDD
Read Data
in
32
26
-HS
Head Select
out
34
6
-DCHG
Disk Change
in
1-33
25,23,21,19,17
GND
Signal grounds
1,3,5
VCC
+5 Volt
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. The speaker must be connected to VCC (and not to Ground).
We propose to use a serial capacitor of 1µF with the speaker to eliminate any DC-current to protect the
speaker itself from overheating.