WebSVN – Kolibri OS – Blame – /contrib/toolchain/avra/examples/throttle_pulse.asm

Rev	Author	Line No.	Line
6400	punk_joker	1	;throttle_pulse.asm
		2
		3	.NOLIST
		4	; ***************************************************************************************
		5	; * PWM MODEL RAILROAD THROTTLE *
		6	; * *
		7	; * WRITTEN BY: PHILIP DEVRIES *
		8	; * *
		9	; * Copyright (C) 2003 Philip DeVries *
		10	; * *
		11	; * This program is free software; you can redistribute it and/or modify *
		12	; * it under the terms of the GNU General Public License as published by *
		13	; * the Free Software Foundation; either version 2 of the License, or *
		14	; * (at your option) any later version. *
		15	; * *
		16	; * This program is distributed in the hope that it will be useful, *
		17	; * but WITHOUT ANY WARRANTY; without even the implied warranty of *
		18	; * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
		19	; * GNU General Public License for more details. *
		20	; * *
		21	; * You should have received a copy of the GNU General Public License *
		22	; * along with this program; if not, write to the Free Software *
		23	; * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA *
		24	; * *
		25	; ***************************************************************************************
		26	.LIST
		27
		28	.ifdef PULSE_ENABLED
		29	;********************************************************************************
		30	;* PULSE_GENERATE *
		31	;* Top level routine *
		32	;* *
		33	;* Inputs: throttle_set *
		34	;* Returns: none *
		35	;* Changed: B_Temp,ramp_target,ramp_target1 *
		36	;* Calls: SET_PWM_DUTY *
		37	;* COUNT_PWM_CYCLES *
		38	;* Goto: none *
		39	;********************************************************************************
		40
		41	HILOCAL1 ramp_target
		42	HILOCAL2 ramp_target1
		43
		44	;*****************************************************************
		45	;* If throttle_set is less than 128 (0x80)
		46	;* Ramp up from wherever the pwm is up to (255 - throttle)
		47	;* If throttle_set is greater than 127 0x7F)
		48	;* Ramp up to throttle_set
		49	;*****************************************************************
		50
		51	mov ramp_target1,throttle_set
		52	sbrs ramp_target1,7
		53
		54	.ifdef PULSE_AMPLITUDE_SCALE
		55	com ramp_target1 ; Ramp up to this value
		56	.else
		57	ldi ramp_target1,0x80
		58	.endif
		59
		60	mov ramp_target,ramp_target1
		61
		62	subi ramp_target,pulse_slope_up ; Ramp up value - pulse_slope
		63
		64	WAIT_FOR_PWM_1: ; Wait for PWM to reset to 0
		65	in B_Temp,TIFR
		66	sbrs B_Temp,OCF1A
		67	rjmp WAIT_FOR_PWM_1
		68
		69	ldi B_Temp,0b01000000
		70	out TIFR,B_Temp
		71
		72	inc Cycle_count
		73
		74	in B_Temp,OCR1A ; Find PWM value
		75	cp B_Temp,ramp_target ; Make sure won't go past max.
		76	brsh DONE_SLOPING_UP
		77
		78	subi B_Temp, 0x100-pulse_slope_up ; OCR1A + pulse_slope_up
		79
		80	rcall SET_PWM_DUTY
		81	rjmp WAIT_FOR_PWM_1
		82
		83	DONE_SLOPING_UP:
		84	mov B_Temp,ramp_target1
		85	rcall SET_PWM_DUTY
		86
		87	;*****************************************************************
		88	;* See if we need to slope down to the throttle setting
		89	;*****************************************************************
		90	in B_Temp,OCR1A ; Find PWM value
		91	cp B_Temp,throttle_set
		92	breq PULSE_GENERATE_RETURN ; Do nothing if already at final voltage
		93
		94	;*****************************************************************
		95	;* Hang about at the top of the pulse for a while...
		96	;*****************************************************************
		97
		98	.ifdef PULSE_WIDTH_SCALE
		99	mov ramp_target1,throttle_set
		100	.else
		101	clr ramp_target1
		102	.endif
		103
		104	add ramp_target1,Cycle_count
		105
		106	subi ramp_target1,0x100-pulse_width_min ; ramp_target1 + pulse_width_min
		107
		108	mov B_Temp1,ramp_target1
		109
		110	rcall COUNT_PWM_CYCLES
		111
		112	;*****************************************************************
		113	;* Slope down
		114	;*****************************************************************
		115
		116	mov ramp_target,throttle_set ; Ramp DOWN to this value
		117
		118	subi ramp_target,0x100-pulse_slope_down ;ramp_target + pulse_slope_down
		119
		120	WAIT_FOR_PWM_2: ; Wait for PWM to reset to 0
		121	in B_Temp,TIFR
		122	sbrs B_Temp,OCF1A
		123	rjmp WAIT_FOR_PWM_2
		124
		125	ldi B_Temp,0b01000000
		126	out TIFR,B_Temp
		127
		128	inc Cycle_count
		129
		130	in B_Temp,OCR1A ; Find PWM value
		131	cp ramp_target,B_Temp ; Make sure won't go past min
		132	brsh PULSE_GENERATE_RETURN
		133
		134	subi B_Temp,pulse_slope_down
		135
		136	rcall SET_PWM_DUTY
		137	rjmp WAIT_FOR_PWM_2
		138
		139	PULSE_GENERATE_RETURN:
		140	.endif ;PULSE_ENABLED

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(root)/contrib/toolchain/avra/examples/throttle_pulse.asm – Rev 6400