;*** Frekvencmeter 1Hz - S53MV 30.04.2014 ***

;*** Konstante mikrokrmilnika LPC2138/01 ***
KVARC	EQU	14745600	;frekvenca kristala (Hz)
CLK	EQU	KVARC*4		;frekvenca jedra ARM (PLL)
PCLK	EQU	CLK		;frekvenca vhodno/izhodnih enot (APBDIV)
BAUD	EQU	PCLK/153600	;modulo deljenja UART za 9600bps*16
N1US	EQU	CLK/3000000	;konstanta cakanja T1US za HD44780

;*** Vhodno/izhodni prikljucki LPC2138/01 ***
;/RESET - vhod vezan na /ERROR.LP2951 in na /DTR.FT231XS
;P0.0/TXD0/PWM1 - izhod vezan na RXD.FT231XS 
;P0.1/RXD0/PWM3/EINT0 - vhod vezan na TXD.FT231XS
;P0.2.od/SCL0/CAP0.0 -
;P0.3.od/SDA0/MAT0.0/EINT1 -
;P0.4/SCK0/CAP0.1/AD0.6 -
;P0.5/MISO0/MAT0.1/AD0.7 -
;P0.6/MOSI0/CAP0.2/AD1.0 -
;P0.7/SSEL0/PWM2/EINT2 -
;P0.8/TXD1/PWM4/AD1.1 -
;P0.9/RXD1/PWM6/EINT3 -
;P0.10/RTS1/CAP1.0/AD1.2 -
;P0.11.od/CTS1/CAP1.1/SCL1 -
;P0.12/DSR1/MAT1.0/AD1.3 -
;P0.13/DTR1/MAT1.1/AD1.4 -
;P0.14.od/DCD1/EINT1/SDA1/BOOTLOADER(!) - vhod vezan na /RTS.FT231XS 
;P0.15/RI1/EINT2/AD1.5 -
;P0.16-23 - digitalni izhodi za LCD D0-7.HD44780
;P0.24 - ne obstaja ***
;P0.25/AD0.4/AOUT -
;P0.26/AD0.5 -
;P0.27/AD0.0/CAP0.1/MAT0.1 -
;P0.28/AD0.1/CAP0.2/MAT0.2 -
;P0.29/AD0.2/CAP0.3/MAT0.3 -
;P0.30/AD0.3/EINT3/CAP0.0 -
;P0.31(!) - nepovezan ***
;P1.0-15 - ne obstajajo ***
;P1.16-19 - vhodi z vgrajenim PULL-UP za tipke na maso
;P1.20(!) - nepovezan ***
;P1.21 - digitalni izhod za LCD RS.HD44780
;P1.22-25 - nepovezani ***
;P1.26(!) - nepovezan ***
;P1.27-29 - nepovezani ***
;P1.30 - digitalni izhod za LCD E.HD44780
;P1.31 - nepovezan ***

;*** Dodelitev pomnilnika RAM ***
SKLAD	EQU	0x40000100	;sklad raste navzdol -256byte

;*** Ukazi za delovanje zbirnika ARM ***
	AREA	RESET, CODE, READONLY, ALIGN=9
	ENTRY
	CODE32

;*** Tabela izjem na zacetnem naslovu 0 ***
IZJEME	B	ZACNI	;RESET
	B	IZJEME	;Undef
	B	IZJEME	;SWI
	B	IZJEME	;PAbt
	B	IZJEME	;DAbt
	NOP		;Reserved Vector
	B	IZJEME	;IRQ
	B	IZJEME	;FIQ

;*** Onemogoci zascito vsebine FLASH na naslovu 0x000001FC ***
	ALIGN	512

;*** Inicializiraj MAM *** (R0-1)
MAM	LDR	R0,=0xE01FC000	;MAMCR=0
	MOV	R1,#0
	STRB	R1,[R0]
	LDR	R0,=0xE01FC004	;MAMTIM=3
	MOV	R1,#3
	STRB	R1,[R0]
	LDR	R0,=0xE01FC000	;MAMCR=2
	MOV	R1,#2
	STRB	R1,[R0]
	MOV	PC,LR
	LTORG

;*** Nastavi PCONP in APBDIV *** (R0-1)
PWRCLK	LDR	R0,=0xE01FC0C4	;PCONP
	LDR	R1,=0x0000102A	;TIM0,UART0,PWM,AD0
	STR	R1,[R0]
	LDR	R0,=0xE01FC100	;APBDIV=1
	MOV	R1,#1
	STRB	R1,[R0]
	MOV	PC,LR
	LTORG

;*** Inicializiraj PLL *** (R0-2)
PLL	LDR	R0,=0xE01FC084	;PLLCFG=0x24 P=2,M-1=3
	MOV	R1,#0x23
	STRB	R1,[R0]
	LDR	R0,=0xE01FC080	;PLLCON=0x01 PLL-enable
	MOV	R1,#0x01
	STRB	R1,[R0]
	LDR	R0,=0xE01FC08C	;PLLFEED
	MOV	R1,#0xAA
	MOV	R2,#0x55
	STRB	R1,[R0]
	STRB	R2,[R0]
PLL1	LDR	R0,=0xE01FC088	;PLLSTAT cakanje uklenitve
	LDR	R1,[R0]
	ANDS	R1,R1,#0x400
	BEQ	PLL1
	LDR	R0,=0xE01FC080	;PLLCON=0x03 PLL-enable&connect
	MOV	R1,#0x03
	STRB	R1,[R0]
	LDR	R0,=0xE01FC08C	;PLLFEED
	MOV	R1,#0xAA
	MOV	R2,#0x55
	STRB	R1,[R0]
	STRB	R2,[R0]
	MOV	PC,LR
	LTORG

;*** Inicializiraj GPIO in DAC *** (R0-1)
GPIO	LDR	R0,=0xE002C000	;PINSEL0
	LDR	R1,=0x0000A005	;P0.0-1=UART0,P0.6=CAP0.2,P0.7=PWM2
	STR	R1,[R0]

	LDR	R0,=0xE002C004	;PINSEL1 P0.25=AOUT
	LDR	R1,=0x00080000
	STR	R1,[R0]
	LDR	R0,=0xE002C014	;PINSEL2 izklop JTAG&TRACE
	LDR	R1,[R0]
	BIC	R1,R1,#0x0C
	STR	R1,[R0]
	LDR	R0,=0xE01FC1A0	;SCS=0x03 high-speed GPIO 0&1
	MOV	R1,#0x03
	STR	R1,[R0]
	LDR	R0,=0x3FFFC014	;FIO0PIN vsi 1
	MOV	R1,#-1
	STR	R1,[R0]
	LDR	R0,=0x3FFFC034	;FIO1PIN vsi 0
	MOV	R1,#0
	STR	R1,[R0]
	LDR	R0,=0x3FFFC000	;FIO0DIR izhodi 0.13-31, vhodi 0.0-12
	LDR	R1,=0xFFFFE000
	STR	R1,[R0]
	LDR	R0,=0x3FFFC020	;FIO1DIR izhodi 1.20-1.31
	LDR	R1,=0xFFF00000
	STR	R1,[R0]
	LDR	R0,=0xE006C000	;DACR sredina skale, visok tok
	LDR	R1,=0x00008000
	STR	R1,[R0]
	MOV	PC,LR
	LTORG

;*** Inicializiraj UART0 *** (R0-1)
UART0	LDR	R0,=0xE000C00C	;U0LCR=0x83 DLAB=1,no-parity,1stop,8bit
	MOV	R1,#0x83
	STRB	R1,[R0]
	LDR	R0,=0xE000C000	;U0DLL 
	LDR	R1,=BAUD
	STRB	R1,[R0]
	LDR	R0,=0xE000C004	;U0DLM
	MOV	R1,R1,LSR#8
	STRB	R1,[R0]
	LDR	R0,=0xE000C008	;U0FCR=0xC1 RXtrig=14bit,FIFOenable
	MOV	R1,#0xC1
	STRB	R1,[R0]
	LDR	R0,=0xE000C00C	;U0LCR=0x03 DLAB=0,no-parity,1stop,8bit
	MOV	R1,#0x03
	STRB	R1,[R0]
	MOV	PC,LR
	LTORG

;*** Inicializiraj HD44780 5X7,2vrstici,CGRAM *** (R0-3)
INILCD	STR	LR,[SP,#-4]!	;resi link
	BL	T100MS		;zakasnitev 100ms
	MOV	R0,#0x38	;function set 
	BL	UKAZ
	BL	T4MS		;zakasnitev 4ms
	MOV	R0,#0x38	;function set
	BL	UKAZ
	MOV	R0,#0x38	;function set
	BL	UKAZ
	MOV	R0,#0x08	;display off
	BL	UKAZ
	MOV	R0,#0x01	;display clear
	BL	UKAZ
	BL	T4MS		;zakasnitev 4ms
	MOV	R0,#0x06	;entry mode set
	BL	UKAZ
	MOV	R0,#0x0C	;display on
	BL	UKAZ
	MOV	R0,#0x40	;set CGRAM address
	BL	UKAZ
	MOV	R2,#64		;prepisi 8 znake = 64 bajtov
	LDR	R3,=INILCD2
INILCD1	LDRB	R0,[R3],#1
	BL	ZNAK
	SUBS	R2,R2,#1
	BNE	INILCD1
	MOV	R0,#0x80	;set DDRAM address zacetek prve vrstice
	BL	UKAZ
	LDR	PC,[SP],#4	;povratek na link
	LTORG
INILCD2	DCB	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x04	;0=praznina
	DCB	0x10,0x10,0x10,0x10,0x10,0x10,0x00,0x04	;1=enacrtica
	DCB	0x14,0x14,0x14,0x14,0x14,0x14,0x00,0x04	;2=dvecrtici
	DCB	0x15,0x15,0x15,0x15,0x15,0x15,0x00,0x04	;3=tricrtice
	DCB	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x1F	;0=praznina podcrtana
	DCB	0x10,0x10,0x10,0x10,0x10,0x10,0x00,0x1F	;1=enacrtica podcrtana
	DCB	0x14,0x14,0x14,0x14,0x14,0x14,0x00,0x1F	;2=dvecrtici podcrtana
	DCB	0x15,0x15,0x15,0x15,0x15,0x15,0x00,0x1F	;3=tricrtice podcrtana
	ALIGN

;*** Podcrtan stolpec v desno v drugi vrstici iz R3 *** (R0-3)
STOLP	STR	LR,[SP,#-4]!	;resi link
	MOV	R0,#0xC0	;set DDRAM address druga vrstica
	BL	UKAZ
	MOV	R2,#0
STOLP1	MOV	R0,#0		;praznina za velike korake po 16
	CMP	R3,#16		;ena crtica?
	MOVCS	R0,#1
	CMP	R3,#32		;dve crtici?
	MOVCS	R0,#2
	CMP	R3,#48		;tri crtice?
	MOVCS	R0,#3
	AND	R1,R3,#15	;podcrtaj pripadajoci znak za male korake po 1
	CMP	R1,R2
	ADDEQ	R0,R0,#4
	BL	ZNAK		;izpisi crtice
	SUBS	R3,R3,#48	;odstej 3 crtice, negativno ustavi?
	ANDMI	R3,R3,#15
	ADD	R2,R2,#1	;zanka 16 znakov
	CMP	R2,#16
	BMI	STOLP1
	LDR	PC,[SP],#4	;povratek na link
	LTORG

;*** Znak iz R0 v HD44780 *** (R0-1)
ZNAK	STR	LR,[SP,#-4]!	;resi link
	LDR	R1,=0x3FFFC016	;FIO0PIN2 podatek
	STRB	R0,[R1]
	LDR	R1,=0x3FFFC03A	;FIO1SET2
	MOV	R0,#0x20	;RS=1
	STRB	R0,[R1]
	BL	T1US		;zakasnitev 1us
	LDR	R1,=0x3FFFC03B	;FIO1SET3
	MOV	R0,#0x40	;vklopi E
	STRB	R0,[R1]
	BL	T1US		;zakasnitev 1us
	LDR	R1,=0x3FFFC03F	;FIO1CLR3
	MOV	R0,#0x40	;izklopi E
	STRB	R0,[R1]
	BL	T100US		;zakasnitev 100us
	LDR	PC,[SP],#4	;povratek na link
	LTORG

;*** Ukaz iz R0 v HD44780 *** (R0-1)
UKAZ	STR	LR,[SP,#-4]!	;resi link
	LDR	R1,=0x3FFFC016	;FIO0PIN2 podatek
	STRB	R0,[R1]
	LDR	R1,=0x3FFFC03E	;FIO1CLR2
	MOV	R0,#0x20	;RS=0
	STRB	R0,[R1]
	BL	T1US		;zakasnitev 1us
	LDR	R1,=0x3FFFC03B	;FIO1SET3
	MOV	R0,#0x40	;vklopi E
	STRB	R0,[R1]
	BL	T1US		;zakasnitev 1us
	LDR	R1,=0x3FFFC03F	;FIO1CLR3
	MOV	R0,#0x40	;izklopi E
	STRB	R0,[R1]
	BL	T100US		;zakasnitev 100us
	LDR	PC,[SP],#4	;povratek na link

;*** Zakasnitev 1us *** (R0)
	ALIGN	16
T1US	MOV	R0,#N1US
T1US1	SUBS	R0,R0,#1
	BPL	T1US1
	MOV	PC,LR

;*** Zakasnitev 100us *** (R0-1)
T100US	STR	LR,[SP,#-4]!	;resi link
	MOV	R1,#100
T100US1	BL	T1US
	SUBS	R1,R1,#1
	BPL	T100US1
	LDR	PC,[SP],#4	;povratek na link

;*** Zakasnitev 4ms *** (R0-2)
T4MS	STR	LR,[SP,#-4]!	;resi link
	MOV	R2,#40
T4MS1	BL	T100US
	SUBS	R2,R2,#1
	BPL	T4MS1
	LDR	PC,[SP],#4	;povratek na link

;*** Zakasnitev 100ms *** (R0-3)
T100MS	STR	LR,[SP,#-4]!	;resi link
	MOV	R3,#25
T100MS1	BL	T4MS
	SUBS	R3,R3,#1
	BPL	T100MS1
	LDR	PC,[SP],#4	;povratek na link

;*** Zakasnitev 1s *** (R0-3)
T1S	STR	LR,[SP,#-4]!	;resi link
	MOV	R3,#250
T1S1	BL	T4MS
	SUBS	R3,R3,#1
	BPL	T1S1
	LDR	PC,[SP],#4	;povratek na link

;*** Zacetek programa po resetu ***
ZACNI	LDR	SP,=SKLAD	;inicializiraj SP
	BL	MAM	;inicializiraj MAM
	BL	PWRCLK	;nastavi PCONP in APBDIV
	BL	PLL	;inicializiraj PLL
	BL	GPIO	;inicializiraj GPIO in DAC
	BL	UART0	;inicializiraj UART0
	BL	INILCD	;inicializiraj HD44780 5X7,2vrstici,CGRAM

	BL	INITIM0
	BL	INIPWM	;inicializiraj PWM

	MOV	R0,#0x80	;prva vrstica besedila
	BL	UKAZ
	LDR	R2,=ZACNI5
ZACNI1	LDRB	R0,[R2],#1
	MOVS	R0,R0
	BEQ	ZACNI2
	BL	ZNAK
	B	ZACNI1
ZACNI2	MOV	R0,#0xC0	;druga vrstica besedila
	BL	UKAZ
	LDR	R2,=ZACNI6
ZACNI3	LDRB	R0,[R2],#1
	MOVS	R0,R0
	BEQ	ZACNI4
	BL	ZNAK
	B	ZACNI3
ZACNI4	BL	T1S		;zakasnitev 1s
	MOV	R8,#31		;zacetni stevec zanke
	MOV	R0,#0x01	;display clear
	BL	UKAZ
	BL	T4MS		;zakasnitev 4ms
	B	ZANKA	;glavna zanka programa
	LTORG
ZACNI5	DCB	"Frekv.meter  1Hz",0
ZACNI6	DCB	"S53MV 30.04.2014",0
	ALIGN	4

;*** Glavna zanka programa ***
ZANKA

ZANKA1	LDR	R0,=0x3FFFC014	;FIO0PIN0
	LDRB	R1,[R0]
	TST	R1,#0x20	;pocakaj konec stetja P0.5=1
	BEQ	ZANKA1

	BL	T100US		;pocajak 100us

	LDR	R0,=0xE0004008	;T0TC izpis razlike Timer Counter 0
	LDR	R3,[R0]
	MOV	R3,R3,LSL#5
	LDR	R0,=0x3FFFC015	;FIO0PIN1
	LDRB	R1,[R0]
	AND	R1,R1,#0x1F
	ORR	R3,R3,R1
	MOV	R1,R3
	SUB	R3,R3,R9
	MOV	R9,R1
	BL	DECIZP

	AND	R3,R8,#0xFF	;izpisi rastoci stolpec v drugo vrstico
	ADD	R3,R3,R3,LSL#1
	BL	STOLP

ZANKA2	LDR	R0,=0x3FFFC014	;FIO0PIN0
	LDRB	R1,[R0]
	TST	R1,#0x20	;pocakaj zacetek stetja P0.5=0
	BNE	ZANKA2

	B ZANKA

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

;;;	TST	R8,#0x04	;izmenicno miganje vseh izhodov
;;;	MOVEQ	R0,#0x55
;;;	MOVNE	R0,#0xAA
;;;	LDR	R1,=0x3FFFC014	;FIO0PIN0 P0.0-7
;;;	STRB	R0,[R1]
;;;	LDR	R1,=0x3FFFC015	;FIO0PIN1 P0.8-15
;;;	STRB	R0,[R1]
;;;	LDR	R1,=0x3FFFC017	;FIO0PIN3 P0.24-31
;;;	STRB	R0,[R1]
;;;	LDR	R0,=0xE000C000	;U0THR izpis stevca na UART0
;;;	STRB	R8,[R0]
;;;	LDR	R0,=0xE006C000	;DACR zaga iz stevca, visok tok
;;;	AND	R1,R8,#0xFF
;;;	MOV	R1,R1,LSL#8
;;;	STR	R1,[R0]

;;;;	BL	T100MS		;zakasnitev 100ms

	ADD	R8,R8,#1	;stevec zanke
	B	ZANKA
	LTORG

;*** Desetiski izpis R3 na LCD *** (R0-4)
DECIZP	STR	LR,[SP,#-4]!
	MOV	R4,#10
DECIZP1	ADD	R0,R4,#0x80	;nastavi polozaj
	BL	UKAZ
	BL	DELI10		;izpisi desetisko mesto
	ADD	R0,R0,#48
	BL	ZNAK
	SUBS	R4,R4,#1
	BPL	DECIZP1
	LDR	PC,[SP],#4

;*** Deli vsebino R3 z 10, ostanek v R0 in kvocient v R3 *** (R0-4)
DELI10	MOV	R0,R3		;deljenec v R0
	MOV	R1,#0xA0000000	;odstevam od deljenca 10*2^N
	MOV	R2,#0x10000000	;pristevam k kvocientu	1*2^N
	MOV	R3,#0		;kvocient v R3
DELI101	SUBS	R0,R0,R1	;odstejem R0-R1
	ADDCS	R3,R3,R2	;ni izposoje >>> pristejem kvocientu R3+R2
	ADDCC	R0,R0,R1	;je izposoja >>> pristejem prevec odsteto R0+R1
	MOV	R1,R1,LSR#1	;pomaknem R1 v desno
	MOVS	R2,R2,LSR#1	;pomaknem R2 v desno, preverim konec zanke!
	BNE	DELI101
	MOV	PC,R14

;*** Inicializacija TIMER0 *** (R0-1)
INITIM0	LDR	R0,=0xE0004070	;T0CTCR
	MOV	R1,#0x0B		;CAP0.2,BOTH
	STRB	R1,[R0]
	LDR	R0,=0xE0004004	;T0TCR
	MOV	R1,#0x01
	STRB	R1,[R0]
	MOV	PC,LR
	LTORG

;*** Inicializacija PWM *** (R0-1)
INIPWM	LDR	R0,=0xE0014014	;PWMMCR
	LDR	R1,=0x00000002	;PWMMR0R
	STR	R1,[R0]
	LDR	R0,=0xE001404C	;PWMPCR
	LDR	R1,=0x00000404	;PWMSEL2,PWMENA2
	STR	R1,[R0]
	LDR	R0,=0xE0014050	;PWMLER
	MOV	R1,#0x07	;Enable PWM latch 0,1,2
	STRB	R1,[R0]
	LDR	R0,=0xE0014018	;PWMMR0
	LDR	R1,=6898250
	STR	R1,[R0]
	LDR	R0,=0xE001401C	;PWMMR1
	LDR	R1,=5898250
	STR	R1,[R0]
	LDR	R0,=0xE0014020	;PWMMR2
	LDR	R1,=10
	STR	R1,[R0]

	LDR	R0,=0xE001400C	;PWMPR
	MOV	R1,#9		;9+1=10
	STR	R1,[R0]		

	LDR	R0,=0xE0014004	;PWMTCR
	MOV	R1,#0x09
	STRB	R1,[R0]
	MOV	PC,LR
	LTORG

;*** Konec delovanja zbirnika ARM ***
	END
