Merge pull request #751 from davidgiven/tartu

Add support for the Tartu Palivere.

README.md

@@ -136,6 +136,7 @@ choices because they can store multiple types of file system.
 | [`rolandd20`](doc/disk-rolandd20.md) | Roland D20: 3.5" electronic synthesiser disks | 🦄 | 🦖 | ROLAND  |
 | [`rx50`](doc/disk-rx50.md) | Digital RX50: 400kB 5.25" 80-track 10-sector SSDD | 🦖 | 🦖 |  |
 | [`smaky6`](doc/disk-smaky6.md) | Smaky 6: 308kB 5.25" 77-track 16-sector SSDD, hard sectored | 🦖 |  | SMAKY6  |
+| [`tartu`](doc/disk-tartu.md) | Tartu: The Palivere and variations | 🦄 |  | CPMFS  |
 | [`tids990`](doc/disk-tids990.md) | Texas Instruments DS990: 1126kB 8" DSSD | 🦖 | 🦖 |  |
 | [`tiki`](doc/disk-tiki.md) | Tiki 100: CP/M |  |  | CPMFS  |
 | [`victor9k`](doc/disk-victor9k.md) | Victor 9000 / Sirius One: 1224kB 5.25" DSDD GCR | 🦖 | 🦖 |  |

arch/build.py

@@ -19,6 +19,7 @@ proto(
         "./northstar/northstar.proto",
         "./rolandd20/rolandd20.proto",
         "./smaky6/smaky6.proto",
+        "./tartu/tartu.proto",
         "./tids990/tids990.proto",
         "./victor9k/victor9k.proto",
         "./zilogmcz/zilogmcz.proto",

arch/smaky6/smaky6.proto

@@ -1,6 +1,4 @@
 syntax = "proto2";
 
-import "lib/common.proto";
-
 message Smaky6DecoderProto {}
 

arch/tartu/decoder.cc

@@ -0,0 +1,84 @@
+#include "lib/globals.h"
+#include "lib/decoders/decoders.h"
+#include "arch/tartu/tartu.h"
+#include "lib/crc.h"
+#include "lib/fluxmap.h"
+#include "lib/decoders/fluxmapreader.h"
+#include "lib/sector.h"
+#include <string.h>
+
+constexpr uint64_t HEADER_BITS = 0xaaaaaaaa44895554LL;
+constexpr uint64_t DATA_BITS =   0xaaaaaaaa44895545LL;
+
+static const FluxPattern HEADER_PATTERN(64, HEADER_BITS);
+static const FluxPattern DATA_PATTERN(64, DATA_BITS);
+
+const FluxMatchers ANY_RECORD_PATTERN {
+    &HEADER_PATTERN,
+    &DATA_PATTERN
+};
+
+class TartuDecoder : public Decoder
+{
+public:
+    TartuDecoder(const DecoderProto& config):
+        Decoder(config),
+        _config(config.tartu())
+    {
+    }
+
+    void beginTrack() override
+    {
+    }
+
+    nanoseconds_t advanceToNextRecord() override
+    {
+        return seekToPattern(ANY_RECORD_PATTERN);
+    }
+
+    void decodeSectorRecord() override
+    {
+        if (readRaw64() != HEADER_BITS)
+            return;
+
+        auto bits = readRawBits(16 * 8);
+        auto bytes = decodeFmMfm(bits).slice(0, 8);
+        
+        ByteReader br(bytes);
+        uint8_t track = br.read_8();
+        _sector->logicalTrack = track >> 1;
+        _sector->logicalSide = track & 1;
+        br.skip(1); /* seems always to be 1 */
+        _sector->logicalSector = br.read_8();
+        uint8_t wantChecksum = br.read_8();
+        uint8_t gotChecksum = ~sumBytes(bytes.slice(0, 3));
+        
+        if (wantChecksum == gotChecksum)
+            _sector->status = Sector::DATA_MISSING;
+
+        _sector->status = Sector::DATA_MISSING;
+    }
+
+    void decodeDataRecord() override
+    {
+        if (readRaw64() != DATA_BITS)
+            return;
+    
+        const auto& bits = readRawBits(129 * 16);
+        const auto& bytes = decodeFmMfm(bits).slice(0, 129);
+        _sector->data = bytes.slice(0, 128);
+
+        uint8_t wantChecksum = bytes.reader().seek(128).read_8();
+        uint8_t gotChecksum = ~sumBytes(_sector->data);
+        _sector->status = (wantChecksum == gotChecksum) ? Sector::OK : Sector::BAD_CHECKSUM;
+    }
+
+private:
+    const TartuDecoderProto& _config;
+};
+
+std::unique_ptr<Decoder> createTartuDecoder(const DecoderProto& config)
+{
+    return std::unique_ptr<Decoder>(new TartuDecoder(config));
+}
+

arch/tartu/tartu.h

@@ -0,0 +1,7 @@
+#ifndef TARTU_H
+#define TARTU_H
+
+extern std::unique_ptr<Decoder> createTartuDecoder(const DecoderProto& config);
+
+#endif
+

arch/tartu/tartu.proto

@@ -0,0 +1,4 @@
+syntax = "proto2";
+
+message TartuDecoderProto {}
+

build.py

@@ -143,6 +143,7 @@ cxxlibrary(
         "./arch/northstar/encoder.cc",
         "./arch/rolandd20/decoder.cc",
         "./arch/smaky6/decoder.cc",
+        "./arch/tartu/decoder.cc",
         "./arch/tids990/decoder.cc",
         "./arch/tids990/encoder.cc",
         "./arch/victor9k/decoder.cc",
@@ -175,6 +176,7 @@ cxxlibrary(
         "arch/micropolis/micropolis.h": "./arch/micropolis/micropolis.h",
         "arch/c64/data_gcr.h": "./arch/c64/data_gcr.h",
         "arch/c64/c64.h": "./arch/c64/c64.h",
+        "arch/tartu/tartu.h": "./arch/tartu/tartu.h",
         "lib/a2r.h": "./lib/a2r.h",
         "lib/bitmap.h": "./lib/bitmap.h",
         "lib/bytes.h": "./lib/bytes.h",

doc/disk-tartu.md

@@ -0,0 +1,43 @@
+tartu
+====
+## The Palivere and variations
+<!-- This file is automatically generated. Do not edit. -->
+
+The Tartu Palivere is a 1988 Z80-based computer from Estonia. It is a CP/M
+machine with 64kB of RAM, running off a 2MHz ꃣ0e30
+clone; it operated off punched tape, cassette, external hard drive or floppy, and was notable as being the first ever computer with an Estonian keyboard.
+
+<div style="text-align: center">
+<img src="tartu.jpg" alt="The Tartu computer's developer Leo Humal working with one."/>
+</div>
+
+From a floppy disk perspective, it is interesting because the floppy drive
+interface is almost entirely handled in software --- necessary at the time as
+the usual floppy disk interface chip at the time, the ⎲fba5
+of the WD1793), was hard to find. Instead, the floppy controller board was
+implemented entirely using TTL logic. Despite this, the encoding is fairly high
+density, using MFM and with up to 780kB on a double-sided 80 track disk.
+
+<div style="text-align: center">
+<img src="tartu-fdc.jpg" alt="The Tartu FDC with Soviet TTL logic chips."/>
+</div>
+
+FluxEngine supports reading Tartu disks with CP/M filesystem access.
+
+## Options
+
+  - Format variants:
+      - `390`: 390kB 5.25" 40-track DSDD
+      - `780`: 780kB 5.25" 80-track DSDD
+
+## Examples
+
+To read:
+
+  - `fluxengine read tartu --390 -s drive:0 -o tartu.img`
+  - `fluxengine read tartu --780 -s drive:0 -o tartu.img`
+
+## References
+
+  - [The Estonia Museum of Electronics](https://www.elektroonikamuuseum.ee/tartu_arvuti_lugu.html)
+

lib/decoders/decoders.cc

@@ -18,6 +18,7 @@
 #include "arch/northstar/northstar.h"
 #include "arch/rolandd20/rolandd20.h"
 #include "arch/smaky6/smaky6.h"
+#include "arch/tartu/tartu.h"
 #include "arch/tids990/tids990.h"
 #include "arch/victor9k/victor9k.h"
 #include "arch/zilogmcz/zilogmcz.h"
@@ -51,6 +52,7 @@ std::unique_ptr<Decoder> Decoder::create(const DecoderProto& config)
             {DecoderProto::kNorthstar,  createNorthstarDecoder  },
             {DecoderProto::kRolandd20,  createRolandD20Decoder  },
             {DecoderProto::kSmaky6,     createSmaky6Decoder     },
+            {DecoderProto::kTartu,      createTartuDecoder      },
             {DecoderProto::kTids990,    createTids990Decoder    },
             {DecoderProto::kVictor9K,   createVictor9kDecoder   },
             {DecoderProto::kZilogmcz,   createZilogMczDecoder   },
@@ -89,7 +91,7 @@ std::shared_ptr<TrackDataFlux> Decoder::decodeToSectors(
         Fluxmap::Position recordStart = fmr.tell();
         _sector->clock = advanceToNextRecord();
         if (fmr.eof() || !_sector->clock)
-            return _trackdata;
+            break;
 
         /* Read the sector record. */
 
@@ -108,28 +110,26 @@ std::shared_ptr<TrackDataFlux> Decoder::decodeToSectors(
         {
             /* The data is in a separate record. */
 
-            for (;;)
+            _sector->headerStartTime = before.ns();
+            _sector->headerEndTime = after.ns();
+
+            _sector->clock = advanceToNextRecord();
+            if (fmr.eof() || !_sector->clock)
+                break;
+
+            before = fmr.tell();
+            decodeDataRecord();
+            after = fmr.tell();
+
+            if (_sector->status != Sector::DATA_MISSING)
+            {
+                _sector->position = before.bytes;
+                _sector->dataStartTime = before.ns();
+                _sector->dataEndTime = after.ns();
+                pushRecord(before, after);
+            }
+            else
             {
-                _sector->headerStartTime = before.ns();
-                _sector->headerEndTime = after.ns();
-
-                _sector->clock = advanceToNextRecord();
-                if (fmr.eof() || !_sector->clock)
-                    break;
-
-                before = fmr.tell();
-                decodeDataRecord();
-                after = fmr.tell();
-
-                if (_sector->status != Sector::DATA_MISSING)
-                {
-                    _sector->position = before.bytes;
-                    _sector->dataStartTime = before.ns();
-                    _sector->dataEndTime = after.ns();
-                    pushRecord(before, after);
-                    break;
-                }
-
                 fmr.skipToEvent(F_BIT_PULSE);
                 resetFluxDecoder();
             }
@@ -142,6 +142,8 @@ std::shared_ptr<TrackDataFlux> Decoder::decodeToSectors(
             _trackdata->sectors.push_back(_sector);
         }
     }
+
+    return _trackdata;
 }
 
 void Decoder::pushRecord(

lib/decoders/decoders.proto

@@ -15,13 +15,14 @@ import "arch/mx/mx.proto";
 import "arch/northstar/northstar.proto";
 import "arch/rolandd20/rolandd20.proto";
 import "arch/smaky6/smaky6.proto";
+import "arch/tartu/tartu.proto";
 import "arch/tids990/tids990.proto";
 import "arch/victor9k/victor9k.proto";
 import "arch/zilogmcz/zilogmcz.proto";
 import "lib/fluxsink/fluxsink.proto";
 import "lib/common.proto";
 
-//NEXT: 32
+//NEXT: 33
 message DecoderProto {
 	optional double pulse_debounce_threshold = 1 [default = 0.30,
 		(help) = "ignore pulses with intervals shorter than this, in fractions of a clock"];
@@ -50,6 +51,7 @@ message DecoderProto {
 		NorthstarDecoderProto northstar = 24;
 		RolandD20DecoderProto rolandd20 = 31;
 		Smaky6DecoderProto smaky6 = 30;
+		TartuDecoderProto tartu = 32;
 		Tids990DecoderProto tids990 = 16;
 		Victor9kDecoderProto victor9k = 17;
 		ZilogMczDecoderProto zilogmcz = 18;

src/formats/build.py

@@ -34,6 +34,7 @@ formats = [
     "rx50",
     "shugart_drive",
     "smaky6",
+    "tartu",
     "tids990",
     "tiki",
     "victor9k",

src/formats/tartu.textpb

@@ -0,0 +1,100 @@
+shortname: 'Tartu'
+comment: 'The Palivere and variations'
+read_support_status: UNICORN
+
+documentation:
+<<<
+The Tartu Palivere is a 1988 Z80-based computer from Estonia. It is a CP/M
+machine with 64kB of RAM, running off a 2MHz КP580ВМ80А, a Soviet Union 8080
+clone; it operated off punched tape, cassette, external hard drive or floppy, and was notable as being the first ever computer with an Estonian keyboard.
+
+<div style="text-align: center">
+<img src="tartu.jpg" alt="The Tartu computer's developer Leo Humal working with one."/>
+</div>
+
+From a floppy disk perspective, it is interesting because the floppy drive
+interface is almost entirely handled in software --- necessary at the time as
+the usual floppy disk interface chip at the time, the КR1818VG93 (a Soviet clone
+of the WD1793), was hard to find. Instead, the floppy controller board was
+implemented entirely using TTL logic. Despite this, the encoding is fairly high
+density, using MFM and with up to 780kB on a double-sided 80 track disk.
+
+<div style="text-align: center">
+<img src="tartu-fdc.jpg" alt="The Tartu FDC with Soviet TTL logic chips."/>
+</div>
+
+FluxEngine supports reading Tartu disks with CP/M filesystem access.
+>>>
+
+documentation:
+<<<
+## References
+
+  - [The Estonia Museum of Electronics](https://www.elektroonikamuuseum.ee/tartu_arvuti_lugu.html)
+>>>
+
+image_writer {
+	filename: "tartu.img"
+	type: IMAGETYPE_IMG
+}
+
+layout {
+	layoutdata {
+		sector_size: 128
+		physical {
+			start_sector: 1
+			count: 39
+		}
+
+		filesystem {
+			start_sector: 1
+			count: 39
+			skew: 3
+		}
+	}
+}
+
+decoder {
+	tartu {}
+}
+
+option_group {
+	comment: "$formats"
+
+	option {
+		name: "390"
+		comment: '390kB 5.25" 40-track DSDD'
+
+		config {
+			layout {
+				format_type: FORMATTYPE_40TRACK
+				tracks: 40
+				sides: 2
+			}
+		}
+	}
+
+	option {
+		name: "780"
+		comment: '780kB 5.25" 80-track DSDD'
+
+		config {
+			layout {
+				format_type: FORMATTYPE_80TRACK
+				tracks: 80
+				sides: 2
+			}
+		}
+	}
+}
+
+filesystem {
+	type: CPMFS
+	cpmfs {
+		filesystem_start {
+			track: 1
+		}
+		block_size: 2048
+		dir_entries: 128
+	}
+}