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Comparing C64 to CPC

3,987 bytes added, 12:41, 9 April 2014
Created page with "== Comparing CPC and C64 == * The C64 was released in 1982, the CPC released in 1984. * The C64 was designed to be connected to a television (PAL: 50Hz, NTSC: 60Hz). The CPC..."
== Comparing CPC and C64 ==

* The C64 was released in 1982, the CPC released in 1984.

* The C64 was designed to be connected to a television (PAL: 50Hz, NTSC: 60Hz). The CPC was designed to be connected to a green screen or colour monitor.

* The C64 has a palette of 16 colours. The Amstrad has a palette of 27 colours.

* The C64 has a 1.0MHz 6510 CPU (a 6502 based CPU). The CPC has a 4.0Mhz Z80 CPU.

* The C64 has a programmable raster interrupt. You can define the line at which the interrupt will be triggered. The CPC has 6 "raster" interrupts at fixed positions through the 50Hz frame.

* The C64 has 50Hz and 60Hz variants (for regions where PAL and NTSC are used), the clocks inside the C64 are based off this. The CPC is 50Hz only.

* The C64's color RAM, SID, VIC and other hardware can be made visible within
the 6510's memory space. Access to them is done using normal read/write operations. All access to the CPC's hardware is done using the Z80's special I/O instructions.

* The C64 has pixel-by-pixel hardware scrolling in both the horizontal and vertical. The CPC has hardware scrolling. Using R5 of the CRTC and Rupture demo technique pixel-by-pixel scrolling in the vertical direction can be achieved. Using R3 of the CRTC 1 byte at a time in the horizontal is possible (which equates to 2 pixels in mode 0, 4 in mode 1, and 8 in mode 2).

* The C64 has the SID sound chip. The CPC has the AY-3-8912 sound chip.

* The C64 has the VIC video chip. The CPC has the 6845 CRTC and Gate-Array.

* The C64 tape loading is done through interrupts so is not intensive on the cpc. The CPC tape loading is intensive on the CPU.

- The C64 communicates with the disc drive through a wired serial connection. This means loading from disc is slow unless a special loader is used.
The CPC's disc interface loads quick.

* The CPC can do overscan (rupture or 32K screen method), the C64 can do it, but only sprites can be displayed where the border was.

==Comparison of the SID and AY-3-8912==

AY sound chip has 3 tone channels, 1 noise channel and 1 hardware envelope.
A mixer can be used to enable/disable tone output for each channel, The volume of each tone channel can be independantly controlled,
OR be controlled by a hardware envelope.


== Comparing Amstrad Plus and C64 ==

* The C64 was released in 1982, the Plus released in 1990.

* The C64 has a palette of 16 colours. The Plus has a palette of 4096 colours.

* The C64 has a 1.0MHz 6510 CPU (a 6502 based CPU with I/O ports based at location &0000 and &0001). The Plus has a 4.0Mhz Z80 CPU.

* Both the C64 and Plus have pixel-by-pixel hardware scrolling both in the horizontal and vertical. (pixel by pixel scrolling requires Plus extra features)

* Both the C64 and Plus have programmable raster interrupts. e.g. you can set whichline of the display an interrupt can occur on.
(requires Plus extra features)

* The C64 has the VIC video chip. The Plus has the ASIC.


== Sprite Comparisons ==

C64:
* The C64 has 8 hardware sprites.
* Each sprites can be one of two resolutions: high resolution or multicolour.
* You can define 1 unique colour for each sprite.
* The priority of sprite-to-sprite is fixed. Sprite 0 has a higher priority than sprite 8.

The pixel size in high resolution is comparable to CPC's mode 1. Each pixel can be either transparent OR a colour unique for each sprite. The pixel size in multicolour is comparable to CPC's mode 0.

* The Plus has 16 hardware sprites. They share a seperate 16 colour palette. They can have a resolution the same as mode 2 or magnified to have a resolution like mode 1 or mode 0. Each sprite is 16x16 pixels.

The Plus sprites can have more colours and are higher resolution compared to the C64's sprites.

(Plus extra features must be activated using a special control sequence.
When this is done, the ASIC registers can be made visible in memory between &4000-&7fff. The Plus registers can then be accessed using normal memory read/write operations).
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