Technical specifications
Processor:
Motorola 68000 16/32-bit processor running at 7.67 MHz
Co-processor (Sound Controller):
Zilog Z80 8-bit at 3.58 MHz
Memory:
64K work RAM (68000), 64K video RAM, 8K work RAM (Z80)
Later hardware had an internal 1Kx8 ROM for the license display screen.
Display Palette:
512 colors (3:3:3 RGB)
Onscreen colors:
64 (normal) or 183 (shadow/highlight mode)
Maximum onscreen sprites:
80 (320-pixel wide displays) or 64 (256-pixel wide displays)
Resolution:
256×224, 256×448, 320×224, 320×448, (PAL and NTSC)
256×240, 320×240, 256×480, 320×480 (PAL only),
256×192 (SMS games only)
Sound:
Yamaha YM2612 5 channel FM and 1 channel FM/PCM, Texas Instruments SN76489 4 channel PSG (Programmable Sound Generator)
(From Wikipedia)