From 0194f9c3bbb460647ce5a22e4e8e7859398d8da0 Mon Sep 17 00:00:00 2001 From: "Juan J. Martinez" Date: Mon, 8 May 2023 22:52:26 +0100 Subject: Support read from the screen --- README.md | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) (limited to 'README.md') diff --git a/README.md b/README.md index 4f70bf0..f8eb7e5 100644 --- a/README.md +++ b/README.md @@ -77,8 +77,10 @@ On a successful port call, the read value equals to the port number, so the call To draw with the blitter the following steps are required: 1. put the blitter in settings mode using control port `0xb0` -2. provide the source address, and destination coordinates (x, y, width and height) using settings port `0xb1` -3. set the blitter in one of the write modes using the control port `0xb0` +2. provide an address, and screen coordinates (x, y, width and height) using settings port `0xb1` +3. set the blitter in one of the draw modes using the control port `0xb0` + +The address will be the source data in write mode, and the destination in read mode. Step 3 can be repeated as many times as needed, the blitter will keep the settings until the control port is set in settings mode. @@ -87,9 +89,10 @@ The settings byte is as follow: | Bits | Effect | --- | --- | | `x0000000` | Set blitter in settings mode | -| `0000000x` | Write | +| `0000000x` | Write to video RAM | | `000000x0` | The source includes a transparent bit | -| `0xxxxx00` | Unused | +| `00000x00` | Read from video RAM | +| `0xxxx000` | Unused | Example: -- cgit v1.2.3