“Jazz” – Audio synthesizer

CPU overclocked from (1x) 150Mhz (1.1v) to (2x) 300Mhz (1.2v), possibly to (3x) 460Mhz (1.5v) – other have driven the RP2350B to over 600Mhz (2v).

Jazz has no flash, it's code is loaded into RAM from DeMon. The flash interface is used for PSRAM (bank 0) access. FRAM is access via GPIO-0, a spare PSRAM bank is accessed via GPIO-8. This allows it to be in one of two modes, (A) two simultaneous banks of PS-RAM or (B) one bank of PS-RAM and FRAM access.

This will both generate sound and play back sampled sound from Audio memory. It will operate like the Commodore SID chip.

Audio in/out will also go from/to the SG2002 “Main processing unit” AND the Razz "pixel controller" (for HDMI output)? If not busy generating audio, this component could also generate video data that could be sent to the “Razz” and mixed with the normal video output. Various audio system emulators will be “built-in” to the firmware.

The Jazz is actually a RP2350B chip combined with a WM8958 (final)/ WM8960 (prototype) chip for audio input/output. In the prototype, the headphone output of the WM8960 also goes to the input of a PCM1808 connected to the Razz chip. This way the Jazz does not need to process/re-encode any audio digitally for it to be mixed in with the video data.

The Jazz has 8MB (optional Interface to 16MB) PSRAM and shared access to 4MB+ FRAM.

The USB port can be used to add a Midi keyboard, Mouse, or to unbrick when used in conjunction with the unbrick button and connected to a PC.

8 10k potentiometers go to dials to simulate various analog instruments such as the TB-303. The colours match the same order as the colours in the Ant64 logo.

64Kbytes of the Jazz RAM could hold a 256x256 256 colour screen that could be sent over the HS TX lines to Razz, this would make a simple overlay that could be applied to whatever screen is being displayed. The slave SPI ports could be used to manipulate this screen from teh SG2002, DeMon or even Razz itself.

FRAM16 map (000000-FFFFFF)

Start address End address Size Description
0000003FFFFF4000004MB SRAM
0400007FFFFF400000Reserved

WM8958 final

Input Source Output Destination
L1 (in1)LSAM (Sampler left) LHP (normally 2nd DAC)Headphone L 5.3mW
R1 (in1)RSAM (Sampler right) RHP (normally 2nd DAC)Headphone R
L2 (in1)Headphone microphone (mono) LSPK (normally 1st DAC)L internal speaker 2W
R2 (in1)From SG2002 audio out (mono) RSPK (normally 1st DACR internal speaker
L3 (in2)Cart L L line out 1
R3 (in2)Cart R R line out 1
L4 (in2) L line out 2
R4 (in2) R line out 2
AIF1 is connected to Jazz, AIF2 is connected to Razz. AIF1 can sample AIF2 initial output. AIF2 can sample the secondary DAC.

WM8960 prototype

Input Source Output Destination
L1LSAM (sampler socket left) LHPFed to Razz PCM1808 (prototype) input & headphone socket L
R1RSAM (sampler socket right) RHPFed to Razz PCM1808 input & headphone socket R
L2Headphone microphone (mono) LSPKLeft internal speaker
R2From SG2002 audio out (mono)RSPKRight internal speaker
L3Cart L
R3Cart R

The SG2002 has a microphone input (connected to the internal Mic), as the SG2002 has a Tensor unit, this could be used for voice recognition. The SG2002 mono audio output can then be fed into R2 for mixing.

GPIO Function GPIO Function
0FRAM 29SPI1 CSn – DeMon slave
1RX0 - From SG2002 30SPI1 SCK – DeMon slave
2TX0 – To DeMon 31HSync interrupt
3PIO/SPI0 TX/MOSI? – SG2002 slave 32PIO/SPI0 RX/MISO? – Razz slave
4PIO/SPI0 RX/MISO? – SG2002 slave 33PIO/SPI0 CSn – Razz slave
5PIO/SPI0 CSn – SG2002 slave 34PIO/SPI0 SCK – Razz slave
6PIO/SPI0 SCK – SG2002 slave 35PIO/SPI0 TX/MOSI? – Razz slave
7VSync interrupt 36Cart 0
8PSRAM CSn (8MB bank 1?) 37Cart 1
9RX1 - From SticKey 38Cart 2
10I2C1 SDA – Controller 3 - Audio settings on address 0x1A/0x34 39Cart 3
11I2C1 SCL – Controller 3 40Analog 0 – green - tuning
12HS TX 0 - to SG2002 41Analog 1 – yellow - cut off
13HS TX 1 - to SG2002 42Analog 2 – orange - resonance
14HS TX 2 - to Razz HS0a - Blue 43Analog 3 – red - envelope
15HS TX 3 - to Razz HS0b 44Analog 4 – purple - decay
16HS TX 4 - to Razz HS1a - Green 45Analog 5 – blue -accent
17HS TX 5 - to Razz HS1b 46Analog 6 – brown - overdrive
18HS TX 6 - to Razz HS2a - Red 47Analog 7 – grey - tone
19HS TX 7 - to Razz HS2a SWDIOConnected to DeMon to
20I2C0 SDA – CART SDA, HDMI 5v SDA SWDCLKallow debug/programming
21I2C0 SCL – ADCREF
22DOUT – to DDAT (DAC input) DACDAT1 3V3
23DIN – to ADAT (ADC output) ADCDAT1 BOOTSEL
24BCLK1 USB D-Mouse / Midi USB HOST port
25LRCK – to DACLRC LRCLK1 USB D+
26ADCLRCLK1 RUNConnected to DeMon
27SPI1 TX/MOSI? – DeMon slave 3V3 EN
28SPI1 RX/MISO? – DeMon slave VBUS

Links

  • youtube.com/watch?v=IYpu-xY-JNk
  • github.com/DatanoiseTV/PicoADK-Hardware
  • youtube.com/watch?v=Of5W7NF73aU (watch 9 min in)
  • youtube.com/watch?v=ianoJ4pmsFE
  • github.com/marcel-licence/ml_synth_organ_example
  • github.com/jonbro/Audcalc
  • Important: The Ant32 and Ant64 are both still at early design and prototype stage, everything you see here is subject to change.