Philips SAA1099 PSG in Verilog for Tiny Tapeout
- Wiki: https://en.wikipedia.org/wiki/Philips_SAA1099 and https://www.wikiwand.com/en/Philips_SAA1099
- Wiki: https://www.vgmpf.com/Wiki/index.php?title=SAA1099
- Manuals: https://www.vgmpf.com/Wiki/images/1/19/SAA1099_-_Manual_-_1984.pdf
- Manuals from SGI: http://www.sgistuff.net/mirrors/4dfaq/#appendixB
- Manuals from Sam Coupe: https://velesoft.speccy.cz/saa1099-cz.htm
- Manuals from Sam Coupe: https://velesoft.speccy.cz/samcoupe/saa1099/saa-1099_pinouts.txt
- Manuals from Sam Coupe: https://velesoft.speccy.cz/samcoupe/saa1099/saa1099-doc5-en.png
- Manuals from Sam Coupe: https://www.worldofsam.org/products/saa1099
Chip technical capabilities
- 6 frequency generators, 8 octaves, 256 tones per octave, frequency range ffrom 31 Hz to 7.81 kHz
- 2 noise generators, range from 61 to 15.6 kHz
- 2 envelope generators
- common clock frequency 8 MHz, the SAA1099s on the GameBlaster are clocked at 7.15909 MHz ( highest frequency the tone generators can reach is about 6.99 kHz)
Historical use of the Philips SAA1099
- Silicon Graphics IRIS Professional 4D and IRIS Power 4D machines
- Creative Sound Blaster 1.0 card
- Sam Coupe home computer
- System 5 arcade game system
Pinout
SAA1099 (Philips)
------------------------
func pin pin func
/WR 1 18 Vcc
/CS 2 17 D7
A0 3 16 D6
OutR 4 15 D5
OutL 5 14 D4
Iref 6 13 D3
/DTACK 7 12 D2
CLK 8 11 D1
GND 9 10 D0
Tests
- envelope test: https://www.youtube.com/watch?v=-ELEH-RX0JE
Recordings from the real chip
- PDM tables by stripwax https://www.vogons.org/viewtopic.php?f=9&t=51695&start=60
- by Jepael http://www.vogons.org/viewtopic.php?f=9&t=51695
- by van Heusden https://vanheusden.com/electronics/SAA1099-clock/
- http://www.etheroneph.com/machinery/529-zvukogenerator-saa1099.html
PDM
AMPLITUDE PDM SEQUENCES
0: 0000000000000000000000000000000000000000000000000000000000000000 = 0
1: 0000000011110000000000000000000000000000000000000000000000000000 = 4/64
2: 0000000000001111111100000000000000000000000000000000000000000000 = 8/64
3: 0000000011111111111100000000000000000000000000000000000000000000 = 12/64
4: 0000000000000000000000000000000000001111111111111111000000000000 = 16/64
5: 0000000011110000000000000000000000001111111111111111000000000000 = 20/64
6: 0000000000001111111100000000000000001111111111111111000000000000 = 24/64
7: 0000000011111111111100000000000000001111111111111111000000000000 = 28/64
8: 1111000000000000000011111111111111110000000000000000111111111111 = 32/64
9: 1111000011110000000011111111111111110000000000000000111111111111 = 36/64
10: 1111000000001111111111111111111111110000000000000000111111111111 = 40/64
11: 1111000011111111111111111111111111110000000000000000111111111111 = 44/64
12: 1111000000000000000011111111111111111111111111111111111111111111 = 48/64
13: 1111000011110000000011111111111111111111111111111111111111111111 = 52/64
14: 1111000000001111111111111111111111111111111111111111111111111111 = 56/64
15: 1111000011111111111111111111111111111111111111111111111111111111 = 60/64
ENVELOPE PDM SEQUENCES
0: 0000000000000000000000000000000000000000000000000000000000000000 = 0/64
1: 0000000000001000000000000000100000000000000010000000000000001000 = 4/64
2: 0000010000000100000001000000010000000100000001000000010000000100 = 8/64
3: 0000010000001100000001000000110000000100000011000000010000001100 = 12/64
4: 0011000000110000001100000011000000110000001100000011000000110000 = 16/64
5: 0011000000111000001100000011100000110000001110000011000000111000 = 20/64
6: 0011010000110100001101000011010000110100001101000011010000110100 = 24/64
7: 0011010000111100001101000011110000110100001111000011010000111100 = 28/64
8: 1100001111000011110000111100001111000011110000111100001111000011 = 32/64
9: 1100001111001011110000111100101111000011110010111100001111001011 = 36/64
10: 1100011111000111110001111100011111000111110001111100011111000111 = 40/64
11: 1100011111001111110001111100111111000111110011111100011111001111 = 44/64
12: 1111001111110011111100111111001111110011111100111111001111110011 = 48/64
13: 1111001111111011111100111111101111110011111110111111001111111011 = 52/64
14: 1111011111110111111101111111011111110111111101111111011111110111 = 56/64
15: 1111011111111111111101111111111111110111111111111111011111111111 = 60/64
Noise
SAA1099P noise generator as documented by Jepael
seed unknown, must be non-zero
18-bit Galois LFSR
Feedback polynomial = x^18 + x^11 + x^1
Period = 2^18-1 = 262143 bits
Verified to match recorded noise from my SAA1099P
Octaves
Apparently that makes the noisegen to be clocked by the undivided octave clock, so lowest octave 0 is same as rate X. And each octave higher doubles the noise frequency.
Notes
B 5
C 33
C# 60
D 85
D# 109
E 132
F 153
F# 173
G 192
G# 210
A 227
A# 243
Implementations
- MAME https://github.com/mamedev/mame/blob/master/src/devices/sound/saa1099.cpp
- Unreal emu, seems to be identical to MAME https://github.com/tslabs/zx-evo/blob/master/pentevo/unreal/Unreal/saa1099.cpp
- System Verilog for MIST Board https://github.com/sorgelig/SAMCoupe_MIST/blob/master/saa1099.sv
- C https://github.com/stripwax/SAASound
- Play MIDI on Arduino with SAA1099: https://github.com/Bobcatmodder/SAATunes
- https://github.com/SudoMaker/RetroWave
What is Tiny Tapeout?
TinyTapeout is an educational project that aims to make it easier and cheaper than ever to get your digital designs manufactured on a real chip.
To learn more and get started, visit https://tinytapeout.com.
Verilog Projects
Edit the info.yaml and uncomment the source_files and top_module properties, and change the value of language to "Verilog". Add your Verilog files to the src folder, and list them in the source_files property.
The GitHub action will automatically build the ASIC files using OpenLane.
How to enable the GitHub actions to build the ASIC files
Please see the instructions for:
Resources
What next?
- Submit your design to the next shuttle on the website. The closing date is November 4th.
- Edit this README and explain your design, how it works, and how to test it.
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