;**************************************************************************************************************** ;This code is for a 3 minute on delay timer that is used on a 3CX1500A7 Linear amp. This delays Plate voltage at ;power turn on. The 3CX1500A7 as well as the 3CX800A7 require a 3 minute warm up before applying plate voltage ;PortB RB0 is used for the output and the clock frequency is 4.0 Mhz. There is a LED tied to RB0 to indicate the ;on state. After the three minute delay the PIC16F84 causes a small dip relay to close which in turn controls ;the contactor in the high voltage power supply. Any time power is dropped to the PIC there is a 3 minute delay ;**************************************************************************************************************** ; ****************************************************************************************** ; * Designer is Pete Juliano. This is a modern day answer to the Amperite Time Delay Relay * ; ****************************************************************************************** List p=16f84 Include "p16f84.inc" __CONFIG 0x3FF9 RB EQU 0x06 LED EQU 0x00 COUNT1 EQU 0x18 COUNT2 EQU 0x19 COUNT3 EQU 0x1A ORG 0x00 GOTO START ;********************Delay Loop 20.02 Sec**************** SEC ;This counter sets up a 20 second delay MOVLW 0x85 MOVWF COUNT1 L1 MOVLW 0xFD MOVWF COUNT2 L2 MOVLW 0xC5 MOVWF COUNT3 L3 DECFSZ COUNT3,1 GOTO L3 DECFSZ COUNT2,1 GOTO L2 DECFSZ COUNT1,1 GOTO L1 MOVLW 0x01 MOVWF COUNT1 LP99 DECFSZ COUNT1,1 GOTO LP99 NOP RETURN ;******************************************************** SEC180 ;By using the call function a 9 X 20 Second delay is produced = 180 Seconds CALL SEC CALL SEC CALL SEC CALL SEC CALL SEC CALL SEC CALL SEC CALL SEC CALL SEC RETURN ;************************************************ START BSF 3,5 MOVLW 0x00 MOVWF RB BCF 3,5 BSF RB,LED CALL SEC180 BCF RB,LED LOOP1 CALL SEC180 ;THis keeps the RB0 high forever! GOTO LOOP1 L200 SLEEP END ;***Actual time is 180.195 Seconds ~ 3 Minutes ****************