Timer from where? What part(s) of the timer do you wish to display?
If it is an Allen Bradley PLC or PAC, the timer structure has sub-elements with the extension ".pre" (preset) and ".acc" (accumulated value). I generally like to put all my HMI stuff in tidy blocks of data, so I would recommend using a MOV instruction in the controller to copy that timer data into a register that is part of your other HMI data and then reference that in the HMI. It is also possible to reference the timer data elements directly if you so choose.