bslathi19/super6502
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02ac7d5213a6563b5b0107e1748a53a6995a5fcc
Commit Graph

144 Commits

Author SHA1 Message Date
Byron Lathi
02ac7d5213 Add diagram, throw some code together 2023-09-07 23:41:17 -07:00
Byron Lathi
5fc71567f2 Add basic mapping 2023-09-06 20:18:36 -07:00
Byron Lathi
18140b32a0 Add null mapper 2023-09-06 19:48:51 -07:00
Byron Lathi
791bffb248 Add copy data back 2023-09-04 14:08:52 -07:00
Byron Lathi
15b7d50a30 Fix zerobss bug 
Well, not really fix but problem is avoided for now
 2023-09-01 21:49:36 -07:00
Byron Lathi
b2b3b84bc4 Kernel crashing 2023-08-26 23:15:36 +00:00
Byron Lathi
eba24c2990 Disable inits which fail 2023-08-26 13:42:06 -07:00
Byron Lathi
0247565f49 Get super simple kernel code running 2023-08-26 13:09:02 -07:00
Byron Lathi
d2700a64fb Read entire file into memory 2023-08-26 08:10:20 -07:00
Byron Lathi
a971e7a717 Start reading options 2023-08-25 20:03:03 -07:00
Byron Lathi
21b456067a Read text and data offset/length 2023-08-25 19:22:21 -07:00
Byron Lathi
8bccfed867 Change segment order to make o65 layout valid 
VECTORS was messing things up
 2023-08-22 20:49:07 -07:00
Byron Lathi
906516c4b5 Add comments and use less magic 2023-08-15 23:06:10 -07:00
Byron Lathi
68ff523b10 Use actual values from sd card 2023-08-15 19:30:11 -07:00
Byron Lathi
053b0d7e3e Find bootloader in FAT 2023-08-12 19:03:24 -07:00
Byron Lathi
fd9389268a Load root directory from sd card 2023-08-12 16:09:03 -07:00
Byron Lathi
6b0caea84c Link bootloader with bios to get access to symbols 
By doing this we don't need to call bios functions, we can just jsr
directly to the addresses. This does mean that everytime the bios
changes the bootloader has to change, but ideally all the bootloader
does is load the bios and then get remapped out of memory. Any important
drivers like file system can be loaded from the bootloader.

This also means that the runtime functions are located in the bios for
the bootloader, so the rom will have to stay mapped in until the kernel
is started, at which point it will have its own runtime and the rom and
bootloader are no longer needed.
 2023-08-08 22:16:42 -07:00
Byron Lathi
e73c4e1d08 Rewrite readblock in assembly 2023-08-08 19:28:10 -07:00
Byron Lathi
446f4e7539 Get bios calls starting to work 2023-08-06 21:41:15 -07:00
Byron Lathi
709c60cf36 SD_command assembly rewrite 2023-07-23 16:25:13 -07:00
Byron Lathi
5ca5fca29b Get SD card working in SPI 2023-07-23 14:55:14 -07:00
Byron Lathi
6a1a76db35 Implement basic SPI controller 2023-07-21 23:01:37 -07:00
Byron Lathi
85f12c75f1 Start spi controller and tb 2023-07-21 22:10:39 -07:00
Byron Lathi
6eeecda368 Add wait states during refresh 2023-07-19 21:06:54 -07:00
Byron Lathi
21e3a477c1 Update IP 2023-07-19 21:06:20 -07:00
Byron Lathi
2f11808f11 Change to simpler rom 2023-01-13 13:07:13 -06:00
Byron Lathi
7682dffe3c Change test program to use correct args 
Seems to work, when you run the test program it resets the card and
sends the voltage and test pattern, and it does receive a response from
the card.
 2023-01-12 21:45:13 -06:00
Byron Lathi
98c07b59b4 Add files from previous version 2023-01-12 17:06:25 -06:00
Byron Lathi
3ff6205e93 Add weak pull up (NEED STRONGER PULLUP) 
weak pullup is enabled, but these are only about 40k when 10k is needed.
I added two 10k resistors to the board.
 2023-01-12 17:05:06 -06:00
Byron Lathi
519cd19739 Add uart2 test program 
Reads input from uart and then writes it back out again immediately.
 2023-01-12 14:05:13 -06:00
Byron Lathi
d5bccd46e3 Add write flag and reset logic for read flag 2023-01-12 14:04:44 -06:00
Byron Lathi
ab46236816 First throw at UART. 2023-01-12 13:34:46 -06:00
Byron Lathi
7e97784992 Create UART and uart_wrapper 2023-01-11 21:16:16 -05:00
Byron Lathi
2f37965464 Add labels for sd mode 2023-01-10 16:58:08 -06:00
Byron Lathi
b5fc0587ac Add labels on fpga side 2023-01-10 16:55:14 -06:00
Byron Lathi
2eaf1d948c Add text labels to arduino pins 
I finally found the schematics for the 385 board so now there can be
labels for what the pins actually do.
 2023-01-10 16:42:44 -06:00
Byron Lathi
4f8e63f463 Update sdram controller with new Efinity version 
For some reason the old one did not want to open in the new version.
Even though the version of the IP is the same, something about it being
made with the old Efinity version made it mad.

I just deleted it and made it again with the same settings and now it
lets me open and configure it.
 2023-01-06 10:28:08 -05:00
Byron Lathi
8181a3a583 Change divider to pipelined version 
The pipelining allows the cpu to run at a faster clock speed but results
in latency. At the current 2 MHz, there is 1 cycle of latency which is
negligible because the 6502 cannot do sequential data memory accesses.

In the future, there will have to be some sort of status flag or
interrupt showing that the divider is ready.
 2023-01-05 19:21:00 -05:00
Byron Lathi
5f6657a227 Add divider 
Adds a 16x16 divider to go with the multiplier.

The divider is a single stage with no pipelining, which works at the
slow 2MHz frequency. Doing this lowers the maximum clock frequency to 5.

This is acceptable for now but means that the cpu can't be run at 14,
which is the maximum frequency.
 2023-01-05 18:35:42 -05:00
Byron Lathi
42ad901ba4 Add multiplier 
Add 16x16 multiplier.

Pretty simple. Address 0-1 is multipled by address 2-3 and the result is
in address 4-7, all little endian of course.
 2023-01-04 16:15:02 -05:00
Byron Lathi
32a78a4aff Add interrupt based timer and test code 2023-01-03 18:20:34 -05:00
Byron Lathi
1ac3bdf614 update timer 
change how timer works, now counter and timer are not separate.
 2023-01-03 15:49:56 -05:00
Byron Lathi
9a2f0a4bb4 Create interrupt controller 2023-01-03 14:50:45 -05:00
Byron Lathi
7bb30abaab Remove unused files 2023-01-03 13:35:10 -05:00
Byron Lathi
d9da0d2bf5 Create 385 IO shield adapter 2023-01-03 13:29:51 -05:00
Byron Lathi
ee8cf1fc37 Make adapter for 385 board 2022-12-30 17:42:11 -05:00
Byron Lathi
ca099a5ef2 Finish routing sd card slot, update gitignore 2022-12-30 15:37:14 -05:00
Byron Lathi
8c4102612f Add timer and test program 2022-12-29 11:51:38 -05:00
Byron Lathi
642dfcbeb1 change to asynchronous read 2022-12-29 11:51:07 -05:00
Byron Lathi
34afd3875c Add timer and testbench 2022-12-29 11:14:32 -05:00