hello: i am working whith a 74c923 keypad decoder conected to port 1 in a 8031 mc, when i read the port, i only can read the entire port and not only p10 trought p14 then when i can use the others 3 bits of the port the port value change and mi code crash, iam using a switch statement in c reading knows values for the 20 diferents keys of the keypad, ie( 0x0,0x1,0x2 to 0x13) anyone knows how can i read the value for only 5 bits occupied for the keypad?
i will appreciated your help...

Best regards