A stop board is typically a large rectangular white sign with a prominent filled red circle on it, usually with the word "Stop" in black underneath, and usually with more wording underneath. Wording is typically along the lines of one of these:
In each case the driver must treat the stop board as a red signal and stop at it, following the instructions, and then proceeding if authorised. Authorisation might be from the signaller, or by the driver's own actions (such as opening crossing gates).
As of V4.5.8.9 SimSig simulates stop boards in one of two ways: ones that require the signaller's permission (i.e. your permission) to pass, and ones which require a non-signaller's authority to pass (e.g. a shunter or the driver him/herself). For the former, the driver will phone you almost immediately for permission to pass the stop board. For the latter, trains will pause briefly at the stop board before continuing without requiring any action from yourself.
Last edited by GeoffM on 15/09/2016 at 03:01