int e l 3.6 DESCRIPTION OF EPROM FILE COMMANDS COMMANDS: PROG3(cr). PROG4(cr), FPROG3(cr), FPROG4(cr) (VERSION 1.1 ONLY) ACTION TAKEN: PROG3 The PROG3 COMMAND functions the same way as the PROG1 COMMAND previously described, except that PROG3 also saves the system control value, MTOP, when it is evoked. During a RESET or power-up sequence MCS BASIC-52 will only clear the external data memory up to the MTOP value that was saved when the PROG3 COMMAND was evoked. This permits the user to "protect" regions of memory from being cleared during a RESET or power-up condition.
In typical use, the PROG3 COMMAND assumes that the user is saving some critical information in some type of battery-backed- up or non-volatile memory and does not want this information to be destroyed during a RESET or power-up sequence. PROG4 The PROG4 COMMAND is a combination of the PROG2 and PROG3 COMMAND. PROG4 saves the same information as PROG3, but also executes the first program stored in the EPROM after a RESET or power-up condition. FPROG3 and FPROG4 The FPROG3 and FPROG4 commands save the same information as the PROG3 and PROG4 commands respectively, except that the INTELIigent(tm) algorithm is used to program the EPROM. VARIATIONS: None. - 26 -