vmem_write() doesn't work correctly in MSX1

[mori0091]

Describe the bug vmem_write() seems buggy in MSX1.

To Reproduce Run MSX1 application such as sample/hello on openmsx with C-BIOS_MSX1_JP. That shows that the VRAM contents is broken.

Expected behavior vmem_write() works correctly.

Development environment (please complete the following information):

• OS and version: Windows 11 / MSYS2 UCRT64
• Compiler and version: sdcc 4.2.0
• Emulator and version: openMSX 18.0
• BIOS and version: C-BIOS_MSX1_JP v0.29

Target Platform

• [x] MSX
• [ ] MSX2
• [ ] MSX2+
• [ ] MSXturboR

Additional context See also issue #50 and PRs related to it. The enhancement of that (i.e. vmem_write_chunk() ) causes this problem.

But this problem seems not occured on WebMSX. Maybe VRAM access timing issue?

[mori0091]

I found the reason. At least in case of MSX1 (i.e. TMS9918 VDP), it needs some wait for VRAM access. Oops. https://www.msx.org/wiki/VRAM_access_speed