fprime/Svc/FpySequencer/docs/sdd.md

Svc::FpySequencer

The FpySequencer is currently in development. Use at own risk

The FpySequencer loads, validates and runs up to one Fpy sequence at a time.

The FpySequencer is primarily composed of a state machine and a runtime environment. The state machine controls the loading, validation, starting and stopping of the sequence, and the actual execution takes place in a sectioned-off runtime.

The FpySequencer runs files compiled by fprime-fpyc (in the fprime-gds package). See the compiler documentation for the details of the Fpy language.

Commands

Name	Description
RUN	Loads, validates and runs a sequence
VALIDATE	Loads and validates a sequence. Mutually exclusive with RUN
RUN_VALIDATED	Must be called after VALIDATE. Runs the sequence that was validated.
CANCEL	Cancels a running or validated sequence. After running CANCEL, the sequencer should return to IDLE

Debugging Commands

The FpySequencer has a set of debugging commands which can be used to pause and step through sequences. They should not be necessary for nominal use cases.

Name	Description
SET_BREAKPOINT	Sets a breakpoint at the specified statement index. When reached, execution will pause before dispatching that statement.
BREAK	Immediately pauses execution before dispatching the next statement. Will break once, then continue normal execution.
CONTINUE	Continues automatic execution of the sequence after it has been paused. If a breakpoint is still set, execution may pause again.
CLEAR_BREAKPOINT	Clears any set breakpoint, but does not continue executing the sequence.
STEP	When paused, executes the next statement then returns to paused state. Not valid during automatic execution.

Directives

Opcode	Name	Description
1	WAIT_REL	Sleeps for a time duration relative to the current time
2	WAIT_ABS	Sleeps until an absolute time is reached
4	GOTO	Sets the index of the next statement to be executed
5	IF	Pops a byte off the stack. If 0, goto a specified statement index, otherwise proceed
6	NO_OP	Does nothing
7	STORE_TLM_VAL	Stores a telemetry buffer in the lvar array
8	STORE_PRM	Stores a parameter buffer in the lvar array
9	CONST_CMD	Dispatches a command with constant arguments
10	OR	Pops two bytes off the stack. If either one is != 0, pushes 1 to stack, otherwise 0
11	AND	Pops two bytes off the stack. If both are != 0, pushes 1 to stack, otherwise 0
12	IEQ	Pops two 8-byte integers off the stack. If they are bitwise equal, pushes 1 to stack, otherwise 0
13	INE	Pops two 8-byte integers off the stack. If they are not bitwise equal, pushes 1 to stack, otherwise 0
14	ULT	Pops two 8-byte unsigned integers off the stack. If the second < first, pushes 1 to stack, otherwise 0
15	ULE	Pops two 8-byte unsigned integers off the stack. If the second <= first, pushes 1 to stack, otherwise 0
16	UGT	Pops two 8-byte unsigned integers off the stack. If the second > first, pushes 1 to stack, otherwise 0
17	UGE	Pops two 8-byte unsigned integers off the stack. If the second >= first, pushes 1 to stack, otherwise 0
18	SLT	Pops two 8-byte signed integers off the stack. If the second < first, pushes 1 to stack, otherwise 0
19	SLE	Pops two 8-byte signed integers off the stack. If the second <= first, pushes 1 to stack, otherwise 0
20	SGT	Pops two 8-byte signed integers off the stack. If the second > first, pushes 1 to stack, otherwise 0
21	SGE	Pops two 8-byte signed integers off the stack. If the second >= first, pushes 1 to stack, otherwise 0
22	FEQ	Pops two 8-byte floats off the stack. If neither is NaN and they are otherwise equal, pushes 1 to stack, otherwise 0
23	FNE	Pops two 8-byte floats off the stack. If neither is NaN and they are otherwise not equal , pushes 1 to stack, otherwise 0
24	FLT	Pops two 8-byte floats off the stack. If neither is NaN and the second < first, pushes 1 to stack, otherwise 0
25	FLE	Pops two 8-byte floats off the stack. If neither is NaN and the second <= first, pushes 1 to stack, otherwise 0
26	FGT	Pops two 8-byte floats off the stack. If neither is NaN and the second > first, pushes 1 to stack, otherwise 0
27	FGE	Pops two 8-byte floats off the stack. If neither is NaN and the second >= first, pushes 1 to stack, otherwise 0
28	NOT	Pops a byte off the stack. If it is != 0, push 0 to stack, otherwise 1
29	FPTOSI	Pops an 8-byte float off the stack, cast it to a signed 8-byte integer and push to the stack
30	FPTOUI	Pops an 8-byte float off the stack, cast it to an unsigned 8-byte integer and push to the stack
31	SITOFP	Pops a signed 8-byte integer off the stack, cast it to an 8-byte float and push to the stack
32	UITOFP	Pops an unsigned 8-byte integer off the stack, cast it to an 8-byte float and push to the stack
33	IADD	Pops two 8-byte integers off the stack. Adds them and pushes the result to stack
34	ISUB	Pops two 8-byte integers off the stack. Subtracts them and pushes the result to stack
35	IMUL	Pops two 8-byte integers off the stack. Multiplies them and pushes the result to stack
36	UDIV	Pops two 8-byte unsigned integers off the stack. Divides them and pushes the result to stack
37	SDIV	Pops two 8-byte signed integers off the stack. Divides them and pushes the result to stack
38	UMOD	Pops two 8-byte unsigned integers off the stack. Computes modulo and pushes the result to stack
39	SMOD	Pops two 8-byte signed integers off the stack. Computes modulo and pushes the result to stack
40	FADD	Pops two 8-byte floats off the stack. Adds them and pushes the result to stack
41	FSUB	Pops two 8-byte floats off the stack. Subtracts them and pushes the result to stack
42	FMUL	Pops two 8-byte floats off the stack. Multiplies them and pushes the result to stack
43	FDIV	Pops two 8-byte floats off the stack. Divides them and pushes the result to stack
44	FLOAT_FLOOR_DIV	Pops two 8-byte floats off the stack. Performs floor division and pushes the result to stack
45	FPOW	Pops two 8-byte floats off the stack. Computes power and pushes the result to stack
46	FLOG	Pops two 8-byte floats off the stack. Computes logarithm and pushes the result to stack
47	FMOD	Pops two 8-byte floats off the stack. Computes modulo and pushes the result to stack
48	FPEXT	Pops a 4-byte float off the stack, cast it to an 8-byte float and push to the stack
49	FPTRUNC	Pops an 8-byte float off the stack, cast it to a 4-byte float and push to the stack
50	SIEXT_8_64	Sign extends an 8-bit integer to 64 bits
51	SIEXT_16_64	Sign extends a 16-bit integer to 64 bits
52	SIEXT_32_64	Sign extends a 32-bit integer to 64 bits
53	ZIEXT_8_64	Zero extends an 8-bit integer to 64 bits
54	ZIEXT_16_64	Zero extends a 16-bit integer to 64 bits
55	ZIEXT_32_64	Zero extends a 32-bit integer to 64 bits
56	ITRUNC_64_8	Truncates a 64-bit integer to 8 bits
57	ITRUNC_64_16	Truncates a 64-bit integer to 16 bits
58	ITRUNC_64_32	Truncates a 64-bit integer to 32 bits
59	EXIT	Pops a byte off the stack. If the byte != 0, end sequence as if it had finished nominally, otherwise end as if a command had failed
60	ALLOCATE	Pushes a hard-coded count of 0-bytes to the stack
61	STORE	Pops a hard-coded number of bytes off the stack, and writes them to the local variable array at a hard-coded offset
62	LOAD	Reads a hard-coded number of bytes from the local variable array at a specific offset, and pushes them to the stack
63	PUSH_VAL	Pushes a constant array of bytes to the stack
64	DISCARD	Discards bytes from the top of the stack
65	MEMCMP	Compares two memory regions on the stack
66	STACK_CMD	Dispatches a command with arguments from the stack
67	PUSH_TLM_VAL_AND_TIME	Gets a telemetry channel and pushes its value, and then its time, onto the stack
68	PUSH_TIME	Pushes the current time, from the timeCaller port, to the stack