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Is the TMS9918 video display processor memory mapped?
The TMS9918 Video Display Processor has always fascinated me, ever since Steve Ciarcia wrote about it in Byte magazine in 1982. Fast forward many years, and now I have several of these devices to play with. The non-memory mapped VRAM is a particularly nice feature for small CPU’s with limited address space – aka Retrocomputing.
How does the Texas Instruments TMS9918A work?
As a byte is written, the TMS9918 increments its internal address register, so that the CPU can quickly write a block of data. Writes to a different port can set various internal registers. There are 4 different screen modes available in the TMS9918A (as mentioned before, the TMS9918 lacks mode Graphic II):
Can a TMS9929A be connected to a TV?
Well, the TMS9929A cannot be connected directly to a TV-in because it doesn’t generate an YPbPr signal but a Y/R-Y/B-Y: the signal is made by luminance (Y) with red (R-Y) and blu e (B-Y) color differences.
What was the challenge of TMS9918 mode 2?
The challenge of using TMS9918 mode 2 was that every 8×1 pixel area could have only two colors, foreground and background. They could be freely picked out of the 16 color palette, but for each 8×1 area, only two colors could exist.
Can you use SRAM for Texas Instruments TMS9918?
This project details how common SRAM can replace the DRAM that is normally required by the Texas Instruments TMS99x8 and TMS9118 Video Display Processor chips. The TMS9918 Video Display Processor has always fascinated me, ever since Steve Ciarcia wrote about it in Byte magazine in 1982.
Can a TMS9918A be connected to a TV?
Insted, the TMS9918A can be connected directly to a TV without the need of any interface: the “magic” is done thanks to the fact the almost every modern TV supports both NTSC and PAL standards. After this introduction to the VDP, I would like to talk about the troubles I encountered while trying to get a decent picture from my computer.