SPT3.8 Assembler Explorer (NXP SPT / Radar Signal Processing Toolbox)

Assemble SPT3.8 source code using a locally installed SPT3.8 toolchain, produce the ELF output, and disassemble it with objdump-spt. Everything -- syntax, mnemonics, operand order, .include directives -- must match the SPT3.8 Assembler Manual.

SPT is a radar signal processing accelerator on S32R. There is no C/C++ compiler. Do not use -mcpu=, -O*, or any ARM flags.

When to use

Use this skill when:

• User asks "assemble this SPT snippet"
• User asks "how does the SPT assembler encode this instruction?"
• User asks "which absolute address does OR_2_5_3 map to?"
• User wants an example of an SPT instruction

Do not use this skill for:

• C/C++ compilation for LAX or ARM
• Section/symbol size analysis -> use spt-binary-analysis

Available Capabilities

Type	Name	Invocation
This skill uses the standardized search_actions + execute_action MCP tool surface.

Action name	Purpose
compiler.list_spt_tools	Discover toolchain and inc/ folder; call first
compiler.spt_execute	Run as-spt, objdump-spt, and other SPT binutils

Quickstart

1. Discover toolchain

Tool:   list_spt_compiler_tools
Output: toolchain_bin_dir, path to inc/ folder (wr.inc, spr.inc, tram.inc, oram.inc)

2. Assemble

Tool:    spt_execute, binary="as-spt"
Input:   args="-I<path_to_inc>", input_code="<source with .include>", input_language="spt"
Output:  a.out (ELF)

3. Disassemble

Tool:    spt_execute, binary="objdump-spt", args="-Dr a.out"
Output:  128-bit instruction listing with 4x32-bit encoding words

Configuration

Include-file mapping (always add the matching .include for symbols used):

Symbol prefix	Include file
WR_0..WR_63	wr.inc
SPR_*, HW_SPR_*, EVT_SPR_*, CHRP_SPR_*	spr.inc
TR_<bank>_<col>_<slice>	tram.inc
OR_<bank>_<col>_<slice>	oram.inc

Assembler key facts:

• Source files must use the .spt extension
• Immediates use # prefix on add, cmp, loop, set, sub
• Operand order is fixed per the manual; do not rearrange
• Output is ARM EABI compatible ELF (32-bit default, -a64 for 64-bit)

Guardrails

Scope

• Only calls list_spt_compiler_tools and spt_execute. No user files modified.

Destructive actions

• All output goes to the tool's isolated scratch directory.

Refuse-and-escalate

• If no SPT3.8 toolchain found, stop and tell the user.
• Do not invent mnemonics, operand values, or instruction forms not in the manual.
• Do not feed C/C++ source to as-spt -- it is assembly-only.
• Do not use stock GNU objdump on SPT ELFs -- use objdump-spt.

Resource limits

• Limit each assembly session to a single snippet or small file.

Secrets

• Do not log source content that may contain sensitive material.

Workflow

Step 1 -- Discover toolchain

Call list_spt_compiler_tools(). Identify toolchain_bin_dir and the inc/ folder.

Step 2 -- Draft the source

1. Identify every symbol prefix used (WR_*, SPR_*, TR_*, OR_*).
2. Add matching .include "<file.inc>" at the top.
3. Use #<value> for immediates on add, cmp, loop, set, sub.
4. Keep operand order exactly as in the manual.
5. Name the file .spt (set input_language: "spt").

Step 3 -- Assemble

{
  "toolchain_bin_dir": "<bin dir>",
  "binary": "as-spt",
  "args": "-I<path_to_inc>",
  "input_code": "<source with .include directives>",
  "input_language": "spt"
}

Step 4 -- Disassemble

{
  "toolchain_bin_dir": "<bin dir>",
  "binary": "objdump-spt",
  "args": "-Dr <artifact_path>"
}

Each 128-bit SPT instruction prints on one line with 4 x 32-bit encoding words. Omitted operands appear explicitly with their implicit encoded value.

Step 5 -- Explain the result

Reprint the disassembly, cite field slicing from the manual, note which operands were omitted and their implicit values, and explain which .include was needed and why.

Validation loop

1. list_spt_compiler_tools() returns a non-empty toolchain list.
2. Every predefined symbol in the source has a matching .include at the top.
3. as-spt exits 0.
4. objdump-spt -Dr output is non-empty and encoding is explained.

Out of scope

• C/C++ compilation (SPT3.8 has no C compiler)
• Section-level size analysis (use spt-binary-analysis)

See Also

• spt-binary-analysis -- section and symbol size analysis