CBS6000 - an 8-bit 6510 computer

u/Keoni29 December 25, 2014, 04:27:33 PM

I need raw uncompressed 8 bit mono PCM @8000Hz samplerate. Max filesize is 55k

u/Dream of Omnimaga December 26, 2014, 12:10:30 AM

Would this unsigned 8 bit PCM do?

u/Keoni29 December 26, 2014, 12:16:06 AM

This still has the WAV header in it. Could you provide me with a headerless file?

u/Dream of Omnimaga December 26, 2014, 03:58:07 AM

How would I do that?

u/Keoni29 December 26, 2014, 08:39:53 AM

There is an option to export headerless files in audacity. Save a file as uncompressed and go to options. Then select RAW(header-less)

u/Dream of Omnimaga December 26, 2014, 09:11:08 AM

What about this?

u/Keoni29 December 26, 2014, 02:50:07 PM

Quote from: DJ Omnimaga on December 26, 2014, 09:11:08 AM
What about this?

Thanks! I will test it on hardware in a bit.

I made a debug routine. It's an interrupt service routine that prints human readable info about the CPU state.
Sample output:

Code Select

A=03,X=08,Y=00,P=34,S=FB,PC=0240
It can be called using a brk instruction or by pulling the IRQ pin low. I want to change this to the NMI because I still want to be able to use interrupts.
I want to make it elaborate on the status flags. It will explain what every flag does like so:

Code Select

Negative number, BRK, INT disabled, Decimal mode enabled

https://raw.githubusercontent.com/keoni29/cbs6000/master/src/main/debug.asm

Edit: I finally fixed a bug in the debugger that prevented it from outputting characters occasionally. I was simply sending characters too fast.

Last Edit: December 26, 2014, 04:42:53 PM by keoni29

u/Dream of Omnimaga December 26, 2014, 05:53:50 PM

Ooh nifty

. By the way lda is kinda like ld in Z80, right? I also can't wait to hear how my sound sample sounds like on your hardware device. Do you think longer samples could be done?

u/Keoni29 December 26, 2014, 07:08:31 PM

It can be done, but it would require bankswitching and/or streaming from a storage device such as a flash chip or sd card.

Edit: Just tried a new kind of digital to analog converter: a bunch of resistors tied to the I/O port. The audio quality is about the same and it takes much less cycles compared to the serial DAC method.

Last Edit: December 26, 2014, 07:18:17 PM by keoni29

u/Dream of Omnimaga December 26, 2014, 10:26:01 PM

Aaah ok, I sometimes don't realize how limited memory is XD. Still, good job

u/Keoni29 December 29, 2014, 11:14:29 AM

I wrote a faster bootloader that uses the serial port of the CIA instead of a software-defined serial port. With the old bootloader it took about a minute to send 55kb to the computer. With the new one this takes less than 5 seconds.

u/Dream of Omnimaga December 29, 2014, 02:28:39 PM

Wow that's fast! By the way is it the time it takes to startup the computer as well or does it startup instantly like non-TI calculators?

u/Keoni29 December 29, 2014, 08:27:39 PM

It does not have an operating system, so loading depends on the size of the file you send to it. The bootloader is ready to receive data a few miliseconds after turning it on.

u/novenary December 29, 2014, 09:49:36 PM

Wow that's some crazy awesome stuff right there Keoni. o.o
ALL HAIL THE KEONI !

u/Keoni29 January 28, 2015, 12:40:25 PM

I am now populating the I/O board. The board connects via a system bus connector to the cpu. The first chip I put on there is a UART. This allows for bi-directional serial communication with a terminal/PC.

Edit: I just tested it and the transmitter seems to work fine. I just sent: Hello World

Edit2: Both sending and receiving characters works. The input is buffered in a 64 byte long buffer. It stops accepting bytes when the buffer is full.

Last Edit: January 28, 2015, 08:35:40 PM by Keoni29