Casio PV-1000/Video

The PV-1000's video timing divides a frame into 288 pixels horizontally by 262 scanlines. The pixel clock is the crystal divided by 4, or roughly 4.47MHz. This corresponds to an exact pixel aspect ratio of 48:35, or approximately 4:3. This makes the horizontal sync rate the quite-slow 15536Hz and the vertical sync rate the almost-normal 59.299Hz

Of those 288 pixels, 224 contain actual video content. These 224 pixels are already significantly wider than the majority of contemporary or even modern TVs can display.

Of the 262 scanlines, 192 contain actual video content. This is significantly shorter than the majority of TVs display. The ASIC draws a solid color of the programmers' choice for 26 scanlines each above and below.

On the 192 active scanlines, the ASIC asserts /BUSREQ for 248 pixels so that the Z80 gets out of the way in time for the ASIC to drive the video, starting 32px before.



Rendering scanlines (n=244; 0-217 and 236-261):

Post-render blanking scanlines (n=3; 218-220):

Vertical sync scanlines (n=3; 221-223):

Pre-render blanking scanlines (n=12; 224-235):