Bus Width Adapter

A 16-bit backbone bus connects to a stack of older 4- and 8-bit parts, and all the glue between them is pure wiring. You are building the adapter. It packs a header and payload into the backbone's word format, tiles a diagnostic pattern across a 16-LED strip, and fixes the byte order of incoming words.

Interface

Port	Direction	Type	Description
`hdr`	in	4-bit vector	Header nibble
`pay`	in	8-bit vector	Payload byte
`word`	out	16-bit vector	Packed backbone word
`pat`	in	4-bit vector	Diagnostic test pattern
`led`	out	16-bit vector	16-LED strip drive
`bus_in`	in	16-bit vector	Word arriving from the backbone
`swap`	out	16-bit vector	`bus_in` with its bytes swapped

Behavior

word follows the backbone's word layout exactly:

Bits Field
15–12 hdr
11–8 constant 0000 (reserved)
7–0 pay
led carries pat repeated four times: bits 15–12, 11–8, 7–4, and 3–0 each show the pattern
swap carries bus_in with its two bytes exchanged: bits 15–8 of swap are bits 7–0 of bus_in, and bits 7–0 of swap are bits 15–8 of bus_in

Bits	Field
15–12	`hdr`
11–8	constant `0000` (reserved)
7–0	`pay`

Constraints

OPERATORS

concatenation (and replication, where your language has it) only; no logic operators, no arithmetic.

STRUCTURE

one concurrent assignment per output; no processes or always blocks.

language-basics combinational

Loading editor...

Click Run to execute your code. Output will appear here.