Chiptune Streaming Protocol:

Host Side

SID Streaming

1. Using SIDDump or SIDDumpR get a dump of SID registers used for each frame.
   HVSC song length files are used to know the playtime. If no song length file is found the default is 3 minutes.

2. The dump is interpreted and a list of values to transmit is generated for each frame. Along with a corresponding bitmap defining which registers are used each frame.
   If SIDDumpHR is used, additional information about hardrestart for each voice is transmitted. This is backwards compatible and only interpreted by terminals supporting it.

3. Each frame register list is built as a data packet taking this form:

Position	Length (bytes)	Description
1	1	Length of this data packet, not counting this byte (max 29)
2	4	Bitmap of SID registers sent. 1 bit = 1 register (Big endian) bits 26-28 indicate ADSR hardrestart for each voice bits 29-31 indicate Gate Hardrestart for each voice
6 onwards	0 to 25	Values of each register, in incremental order by default

PSG Streaming

1. PSG music files are already a register dump, parsing the file will also usually provide metadata, including playtime.
2. The register dump is interpreted and a list of values to transmit is generated for each frame. Along with a corresponding bitmap defining which registers are used each frame.
3. Each frame register list is built as a data packet taking this form:

Position	Length (bytes)	Description
1	1	Length of this data packet, not counting this byte (max 16)
2	2	Bitmap of PSG registers sent. 1 bit = 1 register (Big endian)
4 onwards	0 to 14	Values of each register, in incremental order by default

4. Send the packets according to this flowchart:

%%{ init: { 'flowchart': { 'curve': 'linear' } } }%%
flowchart TD
 id1([Start])
 id2{{Send Chiptune streaming command}}
 id3[Set count to 100]
 id4[/Send Packet/]
 id5{Last Packet?}
 id6[Decrement count]
 id7{Count == 0?}
 id8[/Receive client sync/]
 id9{Sync == $FF?}
 id10[/Send \$00/]
 id11[Flush receive buffer]
 id12([End])
 id13[/Send $FF sync byte/]
 id1-->id2-->id3-->id4-->id13-->id5
 id5-- No -->id6-->id7
 id7-- No -->id4
 id7-- Yes -->id8-->id9
 id9-- No -->id3
 id5 & id9-- Yes -->id10-->id11-->id12

---

Client side flowchart:

%%{ init: { 'flowchart': { 'curve': 'linear' } } }%%
flowchart TD
    id1([Receive streaming command])
    id2{{Set count to 50}}
    id3[/Read data packet/]
    id4[Write registers]
    id5[Decrement count]
    id6{count == 0?}
    id7{user cancel?}
    id8[/Send \$00 sync/]
    id9[Set count to 100]
    id10{Packet size == 0?}
    id11([End streaming])
    id12[/Send $FF sync/]
    id1 ---> id2 --> id3 --> id10 
    id10 -- No --> id4 --> id5 --> id6
    id10 -- Yes --------> id11
    id6 -- Yes --> id7
    id6 -- No --> id3
    id7 -- No --> id8
    id7 -- Yes --> id12
    id8 & id12 --> id9
    id9 --> id3