The Spock Option Byte (R7)

Spock's operation is defined by the Option Byte R7 which has 6 control bits:

Bit NameValue Meaning

5Trigger Type0Trigger operation is Level Sensitive.
1 Trigger operation is Edge Sensitive.
4Edge Direction0 Trigger asserted on FALSE -> TRUE
1 Trigger asserted on TRUE -> FALSE
3Page Selection0 Lower 16K RAM Page and Analog BNC Input.
1 Upper 16K RAM Page and Analog POD Input.
2/1Trig Bit 7 MUX0 DD7 : Digital Data Bus Bit 7.
1 Comparator : trigger match comparator signal.
2 Event 1 : (Pre-scaler output frequency halved).
3 Event 2 : (ADC input frequency halved).
0Trigger Source0 Digital trigger source.
1 Analog trigger source.

Bits 6 and 7 are reserved and should be programmed with zero for compatibility with future Spock revisions. All these bits must be programmed before each data capture trace.

The following pages describe these bits and other Spock registers in more detail.