Roland SPD-20 Owner's Manual page 36

Example 2: Full Set Kit
If you wish to connect a hi-hat control pedal (FD-7; sold separately) to the HH CTRL/TRIG 4 jack, set
the [HH CTRL/TRIG 4] select switch (p. 40) to HH CTRL. If you wish to connect an external pad, set the
switch to TRIG 4.
fig.39
Hi-Hat Control Pedal (FD-7)
HH CTRL/TRIG 4
36
Hi-Hat
Hi-Hat Control Pedal
Pad (PD-120)
Pad (PD-7)
TRIG 3 TRIG 2
TRIG 1
HH CTRL
TRIGGER INPUT (1–3)
/TRIG 4
Crash Splash Ride China
Tom1 Tom2 Tom3 Tom4
Snare
Roland
Kick
Kick Trigger Unit (KD-7)
+ Kick Pedal
Set to HH CTRL