VDP timing analysis tool for MSX

Pedro Gimeno 1e34257333 Remove stray line, minor changes		2 years ago
test_asc2cld	56fe72b2b9 Fix encoding of ELSE	2 years ago
.gitattributes	c8700db72c Add asc2cld.py (BASIC tokenizer) and test suite.	5 years ago
.gitignore	a26a8f425c Fix .gitignore	5 years ago
LICENSE.md	754265982a Rename LICENSE.txt to LICENSE.md, and add it to USAGE.txt	5 years ago
Makefile	946f72a380 In case of failure of loadertpl.py, remove the output file	4 years ago
README.md	3a557cfa52 Update README with more current information	4 years ago
RESULTS.txt	193e9ed01d Minor detail	4 years ago
USAGE.txt	61a29a9c97 Include asc2cld.py in the zip and in USAGE.txt	4 years ago
asc2cas.py	664995375a Couple minor fixes to two auxiliary programs	2 years ago
asc2cld.py	1e34257333 Remove stray line, minor changes	2 years ago
blank1.dsk.gz	274c18382c First commit, based on first public version	5 years ago
blank2.dsk.gz	274c18382c First commit, based on first public version	5 years ago
cld2cas.py	b497f9335a Fix CAS file padding	4 years ago
frametime.bss.asm	58b596792c Drop the Bit Array and change strategy	4 years ago
frametime.code.asm	d2899fc9ea Switch to autolocal labels	4 years ago
im2setup.code.asm	ef4d8794e7 Waste fewer bytes for im2 jump table	4 years ago
im2setup.equ.asm	f998f3f454 Change IM2 table back to low memory	5 years ago
loadertpl.py	c933878689 Move the Y of the sprites 8 pixels down, to let the text be seen	4 years ago
main.bss.asm	0fdef07ede Make AckTiming use next address as temporaries; extend ErrParams	5 years ago
main.code.asm	69639621b6 Clear key buffer on return to BASIC	4 years ago
raw2bin.py	274c18382c First commit, based on first public version	5 years ago
raw2cas.py	664995375a Couple minor fixes to two auxiliary programs	2 years ago
syncvint.code.asm	d2899fc9ea Switch to autolocal labels	4 years ago
sysdefs.equ.asm	69639621b6 Clear key buffer on return to BASIC	4 years ago
test-ack-timing.bss.asm	bc643ccf19 Clean up BASIC now that it's binary; use more meaningful labels	4 years ago
test-ack-timing.code.asm	d6a09ac584 Grammar fix	3 years ago
test-vram-timing.bss.asm	4e745657ac Add write loops for gaps of 19 to 24 cycles between writes	4 years ago
test-vram-timing.code.asm	0008b9d10e Optimize one of the loops, to remove 5 cycles	4 years ago
vdptest.asm	1ecde09b87 Reorganize loader, check if there's enough free memory	4 years ago

VDP Timing Test

This program is designed to test the intricacies and fine details of how the VDP interacts with the CPU, especially in areas of possible interest to emulator authors, and also to MSX/MSX2/MSX2+/TR coders that want to make the most out of the VDP to e.g. squeeze as many transfers as possible in the shortest time.

It's currently work in progress.

An important detail is that it's designed to run on MSX machines with synced CPU/VDP clocks, not separate. This makes things hard for a particular VDP, the Toshiba T6950, at least in PAL machines which need a 22.168 MHz crystal that is not compatible with the regular CPU timings, and therefore always includes separate crystals for CPU and VDP. That leaves several popular Sony machines basically untestable with any degree of reliability.

It's also designed to run on machines with Z80 at 3.579545 MHz and with one M1 wait state, i.e. normal models with no turbo and no R800 mode. It uses ports 98h/99h, it does not read the port number from the BIOS, therefore it will only work in machines that use these ports.

Requires at least 32K to run, and a BASIC ROM (no CBIOS).

See the Releases page for pre-built binaries. Read USAGE.txt for more information.

The license for this code is the Expat license. See the file LICENSE.md for details.

README.md

VDP Timing Test