Next step up would be a SPI device (three pins required) like a Maxim M5450. You could also cascade four 74HC595's to the same effect for less money.
Next after that would be a multiplexed display (11-12 pins required) where 7-8 inputs/outputs are serially connected to the displays and the display anode/cathodes are individually controlled one at a time with transistors.
The maximum would be 28-32 pins where each display is connected to a seperate port. The ports are then switched on and off individually (or multiplexed) in software. That is the way GCBasic handles it with the 7 segment commands. GCBasic online help/7 segment command shows how the pins are hooked up. Get your display data sheet to figure out the segment pinout.
Try the GCBasic way first. If the displays are not bright enough for your taste, then I would go with the 74HC595 route.
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what is the minimum pic needed and how are the displays hooked up to it/communicate?
The minimum would be a 6 pin 10FXXX bit banging I2C (two pins required) commands to a 4 digit controller like:
http://www.semiconductors.com/acrobat/datasheets/SAA1064_CNV_2.pdf
Next step up would be a SPI device (three pins required) like a Maxim M5450. You could also cascade four 74HC595's to the same effect for less money.
Next after that would be a multiplexed display (11-12 pins required) where 7-8 inputs/outputs are serially connected to the displays and the display anode/cathodes are individually controlled one at a time with transistors.
The maximum would be 28-32 pins where each display is connected to a seperate port. The ports are then switched on and off individually (or multiplexed) in software. That is the way GCBasic handles it with the 7 segment commands. GCBasic online help/7 segment command shows how the pins are hooked up. Get your display data sheet to figure out the segment pinout.
Try the GCBasic way first. If the displays are not bright enough for your taste, then I would go with the 74HC595 route.