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Comparing C64 to CPC

524 bytes added, 08:38, 10 April 2014
/* 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 an Amstrad GT65 green screen or CTM640/644 colour monitor.
* The C64 has a special seperate dedicated separate tape player. The CPC464 had has a dedicated tape player built in, or for CPC664 and CPC6128 any tape player could be used with a suitable lead.
* 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 CPUdesign). 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 and you can do this multiple times during a frame. 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 memory read/write operations. All access to the CPC's hardware is done using the Z80's special I/O instructions(IN/OUT). * The C64 has two resolutions: high and multi-colour. The pixel sizes are compareable to Amstrad's mode 1 and mode 0. The Amstrad has 3 display resolutions: low, medium and high. The high resolution on the CPC is higher than the C64's. * The C64 has character and bitmap based modes. The CPC modes are all bitmapped.
* 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 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 very 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 uses a NEC765 disc controller and loads uses byte-by-byte data transfer so is much quicker.
* The C64 can easily play music while loading from tape or disc and do other graphical effects at the same time. The CPC can play music during tape or disc loading but it's more processor intensive and is restricted to no other effects when this is done.
* The CPC can do overscan (rupture or 32K screen method)and any pixels can be shown here, the C64 can do it, but it's more processor intensive and only sprites can be displayed where in this area. (The C64 can open the lower and upper border waswith much less processor time, it takes much more time to open the side borders).
==Comparison of the SID and AY-3-8912==
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