diff --git a/README.md b/README.md index 22f7b27..ac2bfec 100644 --- a/README.md +++ b/README.md @@ -103,19 +103,32 @@ Memory contents can be viewed (and edited) one page at a time through the Memory ![Trace Log] (https://github.com/sethm/symon/raw/master/screenshots/trace_log.png) -The last 20,000 execution steps are disassembled and logged to the Trace Log Window. +The last 20,000 execution steps are disassembled and logged to the Trace Log +Window. -### 3.6 NEW - Experimental 6545 CRTC Video +### 3.6 Simulator Speeds + +![Speeds] (https://github.com/sethm/symon/raw/master/screenshots/simulator_menu.png) + +Simulated speeds may be set from 1MHz to 8MHz. + +### 3.7 Breakpoints + +![Breakpoints] (https://github.com/sethm/symon/raw/master/screenshots/breakpoints.png) + +Breakpoints can be set and removed through the Breakpoints window. + +### 3.8 Experimental 6545 CRTC Video ![Composite Video] (https://github.com/sethm/symon/raw/master/screenshots/video_window.png) -This feature is highly experimental. It's possible to open a video window from the "View" menu. -This window simulates the output of a MOS 6545 CRT Controller located at address `$9000` and -`$9001`. +This feature is highly experimental. It's possible to open a video window +from the "View" menu. This window simulates the output of a MOS 6545 CRT +Controller located at address `$9000` and `$9001`. -By default, the 40 x 25 character display uses video memory located at base address `$7000`. -This means that the memory from address `$7000` (28672 decimal) to `$73E8` (29672 decimal) -is directly mapped to video. +By default, the 40 x 25 character display uses video memory located at base +address `$7000`. This means that the memory from address `$7000` (28672 +decimal) to `$73E8` (29672 decimal) is directly mapped to video. - Address Register (at address `$9000`) - R1: Horizontal Displayed Columns @@ -128,18 +141,20 @@ is directly mapped to video. - R14: Cursor Position (High Byte) - R15: Cursor Position (Low Byte) -Although the simulation is pretty good, there are a few key differences between -the simulated 6545 and a real 6545: +Although the simulation is pretty good, there are a few key differences +between the simulated 6545 and a real 6545: - - The simulated 6545 supports only the straight binary addressing mode of the real 6545, - and not the Row/Column addressing mode. - - The simulated 6545 has full 16 bit addressing, where the real 6545 has only - a 14-bit address bus. - - The simulation is done at a whole-frame level, meaning that lots of - 6545 programming tricks that were achieved by updating the frame address - during vertical and horizontal sync times are not achievable. There is no way - (for example) to change the Display Start Address (R12 and R13) while a - frame is being drawn. + - The simulated 6545 supports only the straight binary addressing + mode of the real 6545, and not the Row/Column addressing mode. + + - The simulated 6545 has full 16 bit addressing, where the real 6545 + has only a 14-bit address bus. + + - The simulation is done at a whole-frame level, meaning that lots + of 6545 programming tricks that were achieved by updating the + frame address during vertical and horizontal sync times are not + achievable. There is no way (for example) to change the Display Start + Address (R12 and R13) while a frame is being drawn. For more information on the 6545 CRTC and its programming model, please see the following resources @@ -148,7 +163,7 @@ For more information on the 6545 CRTC and its programming model, please see the - [MOS 6545 Datasheet (PDF)] (http://www.6502.org/users/andre/hwinfo/crtc/crtc.html) -#### 3.6.1 Example BASIC Program to test Video +#### 3.8.1 Example BASIC Program to test Video This program will fill the video screen with all printable characters. diff --git a/screenshots/breakpoints.png b/screenshots/breakpoints.png new file mode 100644 index 0000000..811956e Binary files /dev/null and b/screenshots/breakpoints.png differ diff --git a/screenshots/full.jpg b/screenshots/full.jpg index 7592420..8b82c2f 100644 Binary files a/screenshots/full.jpg and b/screenshots/full.jpg differ diff --git a/screenshots/simulator_menu.png b/screenshots/simulator_menu.png new file mode 100644 index 0000000..4f0370e Binary files /dev/null and b/screenshots/simulator_menu.png differ