Hola comunidad , tengo una duda con respecto de, conectar directamente 8 led's al portB de un MC9S08QG8, mi duda es basicamente, se es posible conectarlos sin driver de por medio , es decir MCU>resistencisa>led`s.
It's possible to connect 8 LEDs to port B, providing that all the pins on port B can be set as output and one doesn't exceed the maximum pin/port or package sink/source current. Obviously one would need current limiting resistors on each LED. I'd imagine about 5mA per LED is achievable. If say 20mA was required that one would need to use a transistor/mosfet driver etc.
Forgive me but I may not have fully understood your response. I understand that you and your friend are in the first steps of C programming and with Freescale devices. You have found that a ULN2803 device contains 8 darlington transistors and thus you could drive 8 LEDs from it. It's a very popular device but would be perhaps too slow if you are planning to use PWM with the LEDs.
The alternative method as your friend suggests is to simply use one NPN transistor with its respective base and current limiting resistor per LED.
You equally won't damage the micro should you directly connect the LEDs to it but you MUST ensure that you don't exceed the devices maximum current or the ports maximum current.
Hope this helps. Please ask if not! :-)