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Do the framework and hopefully a lot of the maths of the Victor 9K encoder.

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This commit is contained in:
David Given
2021-11-27 23:38:57 +01:00
parent 6247d3c5e6
commit b412d54998
4 changed files with 197 additions and 13 deletions
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8
arch/victor9k/encoder.cc
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@@ -47,8 +47,9 @@ public:
Victor9kEncoderProto::TrackdataProto trackdata;
getTrackFormat(trackdata, physicalTrack, physicalSide);
for (int sectorId : trackdata.sectors().sector())
for (int i = 0; i < trackdata.sector_range().sector_count(); i++)
{
int sectorId = trackdata.sector_range().start_sector() + i;
const auto& sector = image.get(physicalTrack, physicalSide, sectorId);
if (sector)
sectors.push_back(sector);
@@ -63,8 +64,9 @@ public:
Victor9kEncoderProto::TrackdataProto trackdata;
getTrackFormat(trackdata, physicalTrack, physicalSide);
std::vector<bool> bits(trackdata.bits_per_revolution());
unsigned clockRateUs = 166666.0 / trackdata.bits_per_revolution();
unsigned bitsPerRevolution = trackdata.original_data_rate_khz() * trackdata.original_period_ms();
std::vector<bool> bits(bitsPerRevolution);
double clockRateUs = 166666.0 / bitsPerRevolution;
unsigned cursor = 0;
fillBitmapTo(bits, cursor, trackdata.post_index_gap_us() / clockRateUs, { true, false });

12
arch/victor9k/victor9k.proto
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@@ -6,18 +6,20 @@ message Victor9kDecoderProto {}
message Victor9kEncoderProto {
message TrackdataProto {
message SectorsProto {
repeated int32 sector = 1 [(help) = "write these sectors (in order) on each track"];
message SectorRangeProto {
optional int32 start_sector = 1 [(help) = "first sector ID on track"];
optional int32 sector_count = 2 [(help) = "number of sectors on track"];
}
optional int32 min_cylinder = 1 [(help) = "minimum cylinder this format applies to"];
optional int32 max_cylinder = 2 [(help) = "maximum cylinder this format applies to"];
optional int32 head = 3 [(help) = "which head this format applies to"];
optional int32 bits_per_revolution = 4 [(help) = "number of bits on this cylinder"];
optional double post_index_gap_us = 5 [(help) = "size of post-index gap"];
optional double original_period_ms = 4 [(help) = "original rotational period of this cylinder"];
optional double original_data_rate_khz = 5 [(help) = "original data rate of this cylinder"];
optional double post_index_gap_us = 6 [(help) = "size of post-index gap"];
optional SectorsProto sectors = 6 [(help) = "write these sectors (in order) on each track"];
optional SectorRangeProto sector_range = 7 [(help) = "write these sectors on each track"];
}
repeated TrackdataProto trackdata = 1;

20
doc/disk-victor9k.md
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@@ -6,7 +6,25 @@ which used a disk format very reminiscent of the Commodore format; not a
coincidence, as Chuck Peddle designed them both. They're 80-track, 512-byte
sector GCR disks, with a variable-speed drive and a varying number of sectors
per track --- from 19 to 12. Disks can be double-sided, meaning that they can
store 1224kB per disk, which was almost unheard of back then.
store 1224kB per disk, which was almost unheard of back then. Because the way
that the tracks on head 1 are offset from head 0 (this happens with all disks),
the speed zone allocation on head 1 differ from head 0...
| Zone | Head 0 tracks | Head 1 tracks | Sectors | Original period (ms) |
|:----:|:-------------:|:-------------:|:-------:|:--------------------:|
| 0 | 0-3 | | 19 | 237.9 |
| 1 | 4-15 | 0-7 | 18 | 224.5 |
| 2 | 16-26 | 8-18 | 17 | 212.2 |
| 3 | 27-37 | 19-29 | 16 | 199.9 |
| 4 | 38-48 | 30-40 | 15 | 187.6 |
| 5 | 49-59 | 41-51 | 14 | 175.3 |
| 6 | 60-70 | 52-62 | 13 | 163.0 |
| 7 | 71-79 | 63-74 | 12 | 149.6 |
| 8 | | 75-79 | 11 | 144.0 |
(The Original Period column is the original rotation rate. When used in
FluxEngine, the disk always spins at 360 rpm, which corresponds to a rotational
period of 166 ms.)
FluxEngine reads these.

164
src/formats/victor9k.textpb
View File

@@ -1,5 +1,80 @@
comment: 'Victor 9000 / Sirius One 1224kB SSHD GCR variable sector (ro)'
image_reader {
filename: "victor9k.img"
img {
tracks: 80
sides: 1
trackdata {
sector_size: 512
}
trackdata {
track: 0
up_to_track: 3
sector_range {
start_sector: 1
sector_count: 19
}
}
trackdata {
track: 4
up_to_track: 15
sector_range {
start_sector: 1
sector_count: 18
}
}
trackdata {
track: 16
up_to_track: 26
sector_range {
start_sector: 1
sector_count: 17
}
}
trackdata {
track: 27
up_to_track: 37
sector_range {
start_sector: 1
sector_count: 16
}
}
trackdata {
track: 38
up_to_track: 47
sector_range {
start_sector: 1
sector_count: 15
}
}
trackdata {
track: 48
up_to_track: 59
sector_range {
start_sector: 1
sector_count: 14
}
}
trackdata {
track: 60
up_to_track: 70
sector_range {
start_sector: 1
sector_count: 13
}
}
trackdata {
track: 71
up_to_track: 79
sector_range {
start_sector: 1
sector_count: 12
}
}
}
}
image_writer {
filename: "victor9k.img"
img {
@@ -75,9 +150,96 @@ image_writer {
}
}
decoder {
encoder {
victor9k {
trackdata {
original_data_rate_khz: 500
}
trackdata {
head: 0
min_cylinder: 0
max_cylinder: 3
original_period_ms: 237.9
sector_range {
start_sector: 1
sector_count: 19
}
}
trackdata {
head: 0
min_cylinder: 4
max_cylinder: 15
original_period_ms: 224.5
sector_range {
start_sector: 1
sector_count: 18
}
}
trackdata {
head: 0
min_cylinder: 16
max_cylinder: 26
original_period_ms: 212.2
sector_range {
start_sector: 1
sector_count: 17
}
}
trackdata {
head: 0
min_cylinder: 27
max_cylinder: 37
original_period_ms: 199.9
sector_range {
start_sector: 1
sector_count: 16
}
}
trackdata {
head: 0
min_cylinder: 38
max_cylinder: 48
original_period_ms: 187.6
sector_range {
start_sector: 1
sector_count: 15
}
}
trackdata {
head: 0
min_cylinder: 49
max_cylinder: 59
original_period_ms: 175.3
sector_range {
start_sector: 1
sector_count: 14
}
}
trackdata {
head: 0
min_cylinder: 60
max_cylinder: 70
original_period_ms: 163.0
sector_range {
start_sector: 1
sector_count: 13
}
}
trackdata {
head: 0
min_cylinder: 71
max_cylinder: 79
original_period_ms: 149.6
sector_range {
start_sector: 1
sector_count: 12
}
}
}
}
decoder {
victor9k {}
}
cylinders {