How to drive 7 segment using multiple ports?

[guess79]

Dear All, How can I drive 7 segment display with 16F84 using multiple ports (portA.0~3 together with PortB.4~7)?

e.g
' A0 : segment a
' A1 : segment b
' A2 : segment c
' A3 : segment d
' B4 : segment e
' B5 : segment f
' B6 : segment g
' B7 : segment decimal dot

Can any one help me with the following code, please

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digit var Byte
mask var Byte
i var Byte
TRISB = %00000000
TRISA = %00000

loop:

For i = 0 To 9
LookUp, digit (0x3f, 0x06, 0x5b, 0x4f, 0x66, 0x6d, 0x7d, 0x07, 0x7f, 0x6f), mask
"PORTA(A0~A3) + PortB(B4~7) " = mask <--------------- send mask munber to both portA+ portB; this is where i have problem!!!!!!
pause 500
Next i
Goto loop
end