Mrx Expansion Bus K3 - Sinclair MrX Manual

3.

MrX Expansion Bus K3

The MrX Interface is supplied with a built in expansion bus (K3) which allows direct access to the
signals provided by the YM2149 sound chip, should you wish to develop an add-on daughterboard.
Pinout K3:
1) IOB7
2) IOB6
3) IOB5
4) IOB4
5) IOB3
6) IOB2
7) IOB1
8) IOB0
9) IOA7
10) IOA6
11) IOA5
12) IOA4
13) IOA3
14) IOA2
15) IOA1
16) CHL
17) CHR
18) GND
19) /CLK
20) GND
21) ANALOG_CH_C
22) ANALOG_CH_B
23) ANALOG_CH_A
24) VCC
25) GAL1
26) GAL2
27) GAL3
28) GAL4
29) clock/2
30) IOA0
Version: v005
Port B from YM2149
Port B from YM2149
Port B from YM2149
Port B from YM2149
Port B from YM2149
Port B from YM2149
Port B from YM2149
Port B from YM2149
Port A from YM2149
Port A from YM2149
Port A from YM2149
Port A from YM2149
Port A from YM2149
Port A from YM2149
Port A from YM2149
Left channel of 3,5mm jack, behind capacitor
Right channel of 3,5mm jack, behind capacitor
Ground
ZX81 clock signal 3,25 MHz
Ground
Analog Channel C directly connected to YM2149
Analog Channel B directly connected to YM2149
Analog Channel A directly connected to YM2149
Supply current +5V
Pin 15 of GAL 16V8
Pin 14 of GAL 16V8
Pin 13 of GAL 16V8
Pin 12 of GAL 16V8
1,625 MHz
Port A from YM2149
6 Date: 22.05.2012