Ultimate CPC MIDI Card Demo - Line-Out Recording

video upload by Michael Wessel

"A Line Out-recording of the Ultimate CPC MIDI Card - Eye in the Sky.
The X2GS sounds super smooth and offers the best sound quality - you can get one from Serdashop: https://www.serdashop.com/X2GS
Please contact me if you'd like to purchase an Ultimate MIDI Card for the CPC.
https://github.com/lambdamikel/BluePi... The DSK file of this song can be found in the Github repo:
https://github.com/lambdamikel/BluePi... Enjoy!"

Some additional info via Michael:

here is another update from the Ultimate MIDI Card project for the Amstrad CPC!

By now, I have a Python .MID file converter so that I can create MIDI songs for the Ultimate MIDI card on the PC / Mac. Previously, I was recording the complete song .MID MIDI stream in realtime with the CPC. The MIDI message stream was created with a MID file player such as MIDIBAR running on the PC, and then simple fed into the CPC via a USB-2-DIN MIDI cable. For complex multi-track and highly polyphonic MIDI, this was a bit at the limit of what the CPC and BluePill microcontroller can handle, and thus sometimes resulted in dropped or hangind notes for complex MIDI. Hence, a more stable solution was required - the Python-based converter.

Here is a demo of complex converted .MID song played back from CPC memory. Most CPC-users have 512 KBs of extended RAM memory available - the DK'tronics 512 KB RAM expansion is a "standard" even for contemporary CPC RAM expansions. My CPC "converted .MID" player supports 512 KBs of RAM - this is large enough to fit this ~ 96 KBs large BIN song into memory; enjoy the smooth sound of the X2GS sound module plugged into the S2-compatible header at the back of the card."

Building a Drum Computer for the RetroChallenge 2021/11

video upload by Michael Wessel

This one is in via Michael Wessel.

"This is my entry for the RetroChallenge 2021/10.

My Hackaday project page explains some more details"

And via Hackaday:

"In this episode, I extend the pattern-based drum computer to full 16 steps / beats (4 bars x 4 beats), and tailor for real time drum pattern input (like a real drum computer).

This requires inputting data from the keypad using the KIN (Keyboard Input) op-code, whilst playing back the pattern, and hence isn't possible with the standard Microtronic KIN. Thus, I implemented a non-blocking KIN behavior. Utilizing 2 more vacuous op-codes, I can now toggle between the standard blocking KIN input behavior, and the new non-blocking behavior.

The op-codes for determining the KIN mode of operation are 3F0 (blocking KIN mode) and 3F1 (non-blocking KIN mode). By default, the Microtronic only uses blocking KIN. The vacuous op-codes 3F0 and 3F1 are idempotent immediate AND (ANDI) op-codes, i.e., the operand 0xF = 0b1111 = 15 is idempotent for 4bit registers, and hence, no (existing or new) program would ever use them. So it is safe to assign the mode toggling extra side-effect to them.

In general, the following vacuous op-codes are available for side effect extension:

MOV x,x: copy register x onto register x, 0xx
ADDI 0,x: add 0 to register x, 50x
SUBI 0,x: subtract 0 from register x, 70x
ANDI F,x: bitwise AND of register x with F, 3Fx"

Full details on Hackaday.

Amstrad CPC Speak&SID - First Demo of SID Player

Published on Nov 2, 2019 Michael Wessel

"First demo of Speak&SID with the DaDMaN's version of Simon Owen's SID Player. Thanks to DaDMaN from the CPC Wiki Forum for sharing his branch of this player with me, which he had already customized for the CPC! Indeed, it was very little effort to get it running with Speak&SID. I only needed to change the output port and a couple other bits. And worked out of the box, to my surprise! And now - enjoy RoboCup and Commando on the authentic SID 6581.

In case you should be wondering why the sound volume goes low and sounds tinny for a couple of seconds at some point in the video - Speak&SID also feeds into the CPC's internal audio speaker, so at that point I am turning off the amp and let the CPC speaker roar for a bit."

Some additional info in via Mechael Wessel:

"I am cooking up a SID soundcard for the Amstrad CPC

Maybe of some interest to SID / CPC lovers?

'CPC Speak&SID' is a SpeakJet-based speech synthesizer for the CPC, and a SID sound card! It works with the original SID chips, but SwinSID and ARMSID are also valid options. The video shows the original 6581 in action.

The sources for CPC Speak&SID will be made open source soon. The production costs for the card are in the 50 $ range (without the SID chip of course - builders have to source one themselves) Speak&SSID uses the SpeakChip chip for the speech synthesizer, an ATMega 8535 at 16 MHz as the microcontroller, and a Xilinx 9536 CPLD. The SID chip is connected directly to the CPC address and databus though; the CPLD generates the 1 MHz clock signal from the CPC's 4 MHz clock, as well as the other control signals such as R/~W etc.

Unlike the Commodore, the CPC uses IO ports instead of memory mapped registers for hardware interfacing. Hence, the 29 SID chip registers starting at address &d400 to &d41c in the C64 memory are mapped to the CPC's Z80 IO ports &fac0 - &fadc. C64 SID BASIC programs can be ported easily to Speak&SID, simply by replacing the POKE's (PEEK) with OUT (INP) commands, and by adjusting the SID base address.

For the SID Player shown in the video, I am using a version that was already customized by DaDMaN from the CPC Wiki Forum, and it is based on Simon Owen's SID Player for the Z80."

Next-Generation Speech Synthesizer for the Amstrad / Schneider CPC 464 - First PCB Version

Published on May 20, 2017 Michael Wessel

"This is the first PCB version of my Emic 2-based Next-Generation Speech Synthesizer for the Amstrad / Schneider CPC 464. If you would like to purchase one of these, please contact [Michael Wessel on YouTube here]."