; ******************************************************************************
; Copyright © [12/09/1998] Scenix Semiconductor, Inc. All rights reserved.
;
; Scenix Semiconductor, Inc. assumes no responsibility or liability for
; the use of this [product, application, software, any of these products].
; Scenix Semiconductor conveys no license, implicitly or otherwise, under
; any intellectual property rights.
; Information contained in this publication regarding (e.g.: application,
; implementation) and the like is intended through suggestion only and may
; be superseded by updates. Scenix Semiconductor makes no representation
; or warranties with respect to the accuracy or use of these information,
; or infringement of patents arising from such use or otherwise.
;******************************************************************************
;
; Designed for use with Scenix Modem Rev 1.2
;
; Filename: simple_fsk_gen_1_03.src
;
; Authors: Chris Fogelklou
; Applications Engineer
; Scenix Semiconductor, Inc.
;
; Revision: 1.03
;
; Part: SX28AC datecode 9929AA/ SX52BD datecode AB9919AA
; Freq: 50Mhz
;
; Compiled using Parallax SX-Key software v1.07 and SASM 1.40
;
; Date Written: December 9, 1998
; Last Revised: November 22, 1999
;
; Program Description
; This program demonstrates a simple FSK modulation scheme. It contains
; no UART, so the baud rate of the FSK modulation is set by the external
; Terminal's UART. It simply converts high data to a low frequency
; and low data to a high frequency. The analog voltage is generated by
; a 1-pin PDM D/A, and the sine wave values are generated by an artificial
; sine wave generator. This program could be improved by adding a UART to
; the program, and sending the data out after it has been received. Using
; this method, the data can be manipulated.
;
; The FSK modulation constants for other FSK standards besides bell202 are
; also supported, but most require a baud rate generator and flow control.
;
; BELL202: Supported with other BELL202 Modems.
; V.23 Answer Mode: Supported using a 1200bps connection to the modem board,
; but won't be autodetected because it doesn't output 2100Hz
; answer tone for 3 seconds after picking up.
; V.23 Originate Mode: Can't be supported because requires a 75bps baud rate
; generator.
; BELL103 Originate Mode: Supported using a 300bps connection to the board.
; must use another device to dial out.
; BELL103 Answer Mode: Supported using a 300bps connection to the modem board,
; but can't be auto-detected for the same reasons as the
; V.23 Answer mode.
;
; Uncomment the desired modulation type:
;
BELL202
;V23_ORIGINATE_MODE
;V23_ANSWER_MODE
;BELL103_ORIGINATE_MODE
;BELL103_ANSWER_MODE
;
; Revision History:
; 1.01 & 1.02: Documentation Updates.
; 1.03: Updated for new SX template, and Modem Boards, Rev 1.2
;
; Pins Used:
; PDM_pin equ ra.0 ; D/A output pin, connect to filter circuitry
; rx_pin equ ra.1 ; RS-232 reception pin
; tx_pin equ ra.2 ; RS-232 transmission pin, received characters
; ; are echoed on this pin.
; led_pin equ rb.0 ; LED pin... Flashes when characters are received
; hook equ rb.4 ; drive hook low to go off-hook
; cts equ rb.7 ; indicates to the PC that the SX is ready to
; ; receive data
;
;******************************************************************************
;*****************************************************************************************
; Target SX
; Uncomment one of the following lines to choose the SX18AC, SX20AC, SX28AC, SX48BD/ES,
; SX48BD, SX52BD/ES or SX52BD. For SX48BD/ES and SX52BD/ES, uncomment both defines,
; SX48_52 and SX48_52_ES.
;*****************************************************************************************
;SX18_20
SX28
;SX48_52
;SX48_52_ES
;*****************************************************************************************
; Assembler Used
; Uncomment the following line if using the Parallax SX-Key assembler. SASM assembler
; enabled by default.
;*****************************************************************************************
;SX_Key
;*********************************************************************************
; Assembler directives:
; high speed external osc, turbo mode, 8-level stack, and extended option reg.
;
; SX18/20/28 - 4 pages of program memory and 8 banks of RAM enabled by default.
; SX48/52 - 8 pages of program memory and 16 banks of RAM enabled by default.
;
;*********************************************************************************
IFDEF SX_Key ;SX-Key Directives
IFDEF SX18_20 ;SX18AC or SX20AC device directives for SX-Key
device SX18L,oschs2,turbo,stackx_optionx
ENDIF
IFDEF SX28 ;SX28AC device directives for SX-Key
device SX28L,oschs2,turbo,stackx_optionx
ENDIF
IFDEF SX48_52_ES ;SX48BD/ES or SX52BD/ES device directives for SX-Key
device oschs,turbo,stackx,optionx
ELSE
IFDEF SX48_52 ;SX48/52/BD device directives for SX-Key
device oschs2
ENDIF
ENDIF
freq 50_000_000
ELSE ;SASM Directives
IFDEF SX18_20 ;SX18AC or SX20AC device directives for SASM
device SX18,oschs2,turbo,stackx,optionx
ENDIF
IFDEF SX28 ;SX28AC device directives for SASM
device SX28,oschs2,turbo,stackx,optionx
ENDIF
IFDEF SX48_52_ES ;SX48BD/ES or SX52BD/ES device directives for SASM
device SX52,oschs,turbo,stackx,optionx
ELSE
IFDEF SX48_52 ;SX48BD or SX52BD device directives for SASM
device SX52,oschs2
ENDIF
ENDIF
ENDIF
ID 'FSK_TX10' ; Version = 1.01
reset reset_entry ; JUMP to start label on reset
;*****************************************************************************************
; Macros
;*****************************************************************************************
;*********************************************************************************
; Macro: _bank
; Sets the bank appropriately for all revisions of SX.
;
; This is required since the bank instruction has only a 3-bit operand, it cannot
; be used to access all 16 banks of the SX48/52. For this reason FSR.4 (for SX48/52BD/ES)
; or FSR.7 (SX48/52bd production release) needs to be set appropriately, depending
; on the bank address being accessed. This macro fixes this.
;
; So, instead of using the bank instruction to switch between banks, use _bank instead.
;
;*********************************************************************************
_bank macro 1
bank \1
IFDEF SX48_52
IFDEF SX48_52_ES
IF \1 & %00010000 ;SX48BD/ES and SX52BD/ES (engineering sample) bank instruction
setb fsr.4 ;modifies FSR bits 5,6 and 7. FSR.4 needs to be set by software.
ENDIF
ELSE
IF \1 & %10000000 ;SX48BD and SX52BD (production release) bank instruction
setb fsr.7 ;modifies FSR bits 4,5 and 6. FSR.7 needs to be set by software.
ELSE
clrb fsr.7
ENDIF
ENDIF
ENDIF
endm
;*********************************************************************************
; Macro: _mode
; Sets the MODE register appropriately for all revisions of SX.
;
; This is required since the MODE (or MOV M,#) instruction has only a 4-bit operand.
; The SX18/20/28AC use only 4 bits of the MODE register, however the SX48/52BD have
; the added ability of reading or writing some of the MODE registers, and therefore use
; 5-bits of the MODE register. The MOV M,W instruction modifies all 8-bits of the
; MODE register, so this instruction must be used on the SX48/52BD to make sure the MODE
; register is written with the correct value. This macro fixes this.
;
; So, instead of using the MODE or MOV M,# instructions to load the M register, use
; _mode instead.
;
;*********************************************************************************
_mode macro 1
IFDEF SX48_52
mov w,#\1 ;loads the M register correctly for the SX48BD and SX52BD
mov m,w
ELSE
mov m,#\1 ;loads the M register correctly for the SX18AC, SX20AC
;and SX28AC
ENDIF
endm
;*****************************************************************************************
; Error generating macros
;*****************************************************************************************
tableStart macro 0 ; Generates an error message if code that MUST be in
; the first half of a page is moved into the second half.
if $ & $100
ERROR 'Must be located in the first half of a page.'
endif
endm
tableEnd macro 0 ; Generates an error message if code that MUST be in
; the first half of a page is moved into the second half.
if $ & $100
ERROR 'Must be located in the first half of a page.'
endif
endm
;*****************************************************************************************
; Data Memory address definitions
; These definitions ensure the proper address is used for banks 0 - 7 for 2K SX devices
; (SX18/20/28) and 4K SX devices (SX48/52).
;*****************************************************************************************
IFDEF SX48_52
global_org = $0A
bank0_org = $00
bank1_org = $10
bank2_org = $20
bank3_org = $30
bank4_org = $40
bank5_org = $50
bank6_org = $60
bank7_org = $70
ELSE
global_org = $08
bank0_org = $10
bank1_org = $30
bank2_org = $50
bank3_org = $70
bank4_org = $90
bank5_org = $B0
bank6_org = $D0
bank7_org = $F0
ENDIF
;*****************************************************************************************
; Global Register definitions
; NOTE: Global data memory starts at $0A on SX48/52 and $08 on SX18/20/28.
;*****************************************************************************************
org global_org
flags0 equ global_org + 0 ; bit-storage register
flags1 equ global_org + 1 ; bit-storage register 2
localTemp0 equ global_org + 2 ; temporary storage register
localTemp1 equ global_org + 3 ; temporary storage register
localTemp2 equ global_org + 4 ; temporary storage register
isrTemp0 equ global_org + 5 ; Interrupt Service Routine's temp register.
; Don't use this register in the mainline.
;*****************************************************************************************
; RAM Bank Register definitions
;*****************************************************************************************
;*********************************************************************************
; Bank 0
;*********************************************************************************
org bank0_org
bank0 = $
;*********************************************************************************
; Bank 1
;*********************************************************************************
org bank1_org
bank1 = $
;VP: artificial sine generation
sin_gen_bank = $
freq_acc_low ds 1 ; 16-bit accumulator which decides when to increment the sine wave
freq_acc_high ds 1 ;
freq_count_low ds 1 ; 16-bit counter which decides which frequency for the sine wave
freq_count_high ds 1 ; freq_count = Frequency * 6.83671552
sin ds 1 ; The current value of the imitation sin wave
sinvel ds 1 ; The velocity of the sin wave
;VP: PDM D/A VP
PDM_bank = $
PDM0_acc ds 1 ; PDM accumulator
PDM0_out ds 1 ; current PDM output (D/A)
;*********************************************************************************
; Bank 2
;*********************************************************************************
org bank2_org
bank2 = $
;*********************************************************************************
; Bank 3
;*********************************************************************************
org bank3_org
bank3 = $
;*********************************************************************************
; Bank 4
;*********************************************************************************
org bank4_org
bank4 = $
;*********************************************************************************
; Bank 5
;*********************************************************************************
org bank5_org
bank5 = $
;*********************************************************************************
; Bank 6
;*********************************************************************************
org bank6_org
bank6 = $
;*********************************************************************************
; Bank 7
;*********************************************************************************
org bank7_org
bank7 = $
IFDEF SX48_52
;*********************************************************************************
; Bank 8
;*********************************************************************************
org $80 ;bank 8 address on SX52
bank8 = $
;*********************************************************************************
; Bank 9
;*********************************************************************************
org $90 ;bank 9 address on SX52
bank9 = $
;*********************************************************************************
; Bank A
;*********************************************************************************
org $A0 ;bank A address on SX52
bankA = $
;*********************************************************************************
; Bank B
;*********************************************************************************
org $B0 ;bank B address on SX52
bankB = $
;*********************************************************************************
; Bank C
;*********************************************************************************
org $C0 ;bank C address on SX52
bankC = $
;*********************************************************************************
; Bank D
;*********************************************************************************
org $D0 ;bank D address on SX52
bankD = $
;*********************************************************************************
; Bank E
;*********************************************************************************
org $E0 ;bank E address on SX52
bankE = $
;*********************************************************************************
; Bank F
;*********************************************************************************
org $F0 ;bank F address on SX52
bankF = $
ENDIF
;*********************************************************************************
; Pin Definitions: These are the pins on the Scenix Modem board. Not all are
; necessary. Check the documentation at the top of this
; program.
;*********************************************************************************
PDM_pin equ ra.0 ; D/A output pin
rx_pin equ ra.1 ; RS-232 reception pin
tx_pin equ ra.2 ; RS-232 transmission pin
nothing equ ra.3 ; N/C
RA_latch equ %11111111 ;SX18/20/28/48/52 port A latch init
RA_DDIR equ %11111010 ;SX18/20/28/48/52 port A DDIR value
RA_LVL equ %00000000 ;SX18/20/28/48/52 port A LVL value
RA_PLP equ %11111111 ;SX18/20/28/48/52 port A PLP value
led_pin equ rb.0 ; LED pin
rxa_pin equ rb.1 ; FSK receive pin
cntrl_1 equ rb.2 ; drive cntrl_1 low to disable the output of the LPF
ring equ rb.3 ; ring detection pin
hook equ rb.4 ; drive hook low to go off-hook
cntrl_3 equ rb.5 ; drive cntrl_3 low to disable the output of the HPF
rts equ rb.6 ; indicates to the SX that the PC wants to transmit data
cts equ rb.7 ; indicates to the PC that the SX is ready to receive data
RB_latch equ %11011011 ;SX18/20/28/48/52 port B latch init
RB_DDIR equ %01101110 ;SX18/20/28/48/52 port B DDIR value
RB_ST equ %11111111 ;SX18/20/28/48/52 port B ST value
RB_LVL equ %00000000 ;SX18/20/28/48/52 port B LVL value
RB_PLP equ %11111111 ;SX18/20/28/48/52 port B PLP value
dtmf_in_pin equ rc.0 ; DTMF input pin
dtmf_fdbk_pin equ rc.1 ; Negative feedback output for DTMF input
AtoD_in_pin equ rc.2 ; A/D input pin
AtoD_fdbk_pin equ rc.3 ; Negative feedback for A/D input
imp_450_pin equ rc.4 ; Set to an output to set hybrid for 450ohm line impedance. Tristate otherwise.
imp_600_pin equ rc.5 ; Set to an output to set hybrid for 600ohm line impedance. Tristate otherwise.
imp_750_pin equ rc.6 ; Set to an output to set hybrid for 750ohm line impedance. Tristate otherwise.
imp_900_pin equ rc.7 ; Set to an output to set hybrid for 900ohm line impedance. Tristate otherwise.
RC_latch equ %00001111 ;SX18/20/28/48/52 port C latch init
RC_DDIR equ %11010101 ;SX18/20/28/48/52 port C DDIR value
RC_ST equ %11111111 ;SX18/20/28/48/52 port C ST value
RC_LVL equ %00000000 ;SX18/20/28/48/52 port C LVL value
RC_PLP equ %11111111 ;SX18/20/28/48/52 port C PLP value
IFDEF SX48_52 ;SX48BD/52BD Port initialization values
RD_latch equ %00000000 ;SX48/52 port D latch init
RD_DDIR equ %11111111 ;SX48/52 port D DDIR value
RD_ST equ %11111111 ;SX48/52 port D ST value
RD_LVL equ %00000000 ;SX48/52 port D LVL value
RD_PLP equ %11111111 ;SX48/52 port D PLP value
RE_latch equ %00000000 ;SX48/52 port E latch init
RE_DDIR equ %11111111 ;SX48/52 port E DDIR value
RE_ST equ %11111111 ;SX48/52 port E ST value
RE_LVL equ %00000000 ;SX48/52 port E LVL value
RE_PLP equ %11111111 ;SX48/52 port E PLP value
ENDIF
;*****************************************************************************************
; Program constants
;*****************************************************************************************
;-------------------------------------------------------------------------------------
; The constant = 2^n * Ts * FREQ,
; where n is the number of bits in the phase accumulator for each
; signal generator, Ts is the sample rate, and FREQ is the desired
; output frequency.
; We know that the phase accumulator (freq_count) is 16 bits, and each
; time that the phase accumulator rolls over, the sine wave is advanced
; another of 32 states, giving an effective bit count in the phase
; accumulator of 21, so n = 21
; We will choose a phase update rate of 306.7kHz for the FSK Generation
; = 1/([cyclesperinterupt] * [instructiontime] * [ISR passes])
; = 1/(163 * 20ns * 1 passes)
; Therefore, the constant = 2^n * (1/Fs) * FREQ
; Convert the result of the calculation to a hexadecimal number and load
; the upper byte into the freq_count_high register and the lower byte
; into the freq_count_low register.
;-------------------------------------------------------------------------------------
;VP: FSK Generation using the artificial sine generator
f390_l equ $6a ; V.23 originating mode channel logic '1' (mark)
f390_h equ $0a
f450_l equ $04 ; V.23 originating mode channel logic '0' (space)
f450_h equ $0c
f1300_l equ $b7 ; V.23 answer mode & Bell202 channel logic '1' (mark)
f1300_h equ $22
f2100_l equ $15 ; V.23 answer mode & Bell202 channel logic '0' (space)
f2100_h equ $38
f2225_l equ $6b ; Bell 103 answer mode channel logic '1' (mark)
f2225_h equ $3b
f2025_l equ $14 ; Bell 103 answer mode channel logic '0' (space)
f2025_h equ $36
f1270_l equ $ea ; Bell 103 originating mode channel logic '1' (mark)
f1270_h equ $21
f1070_l equ $93 ; Bell 103 originating mode channel logic '0' (space)
f1070_h equ $1c
IFDEF V23_ORIGINATE_MODE
F0_l equ f450_l
F0_h equ f450_h
F1_l equ f390_l
F1_h equ f390_h
;----------------------------------------------------
; *** Sample_rate/128 = 9600/128 = 75bps
;----------------------------------------------------
fsk_tx_baud_bit = 7 ;
ENDIF
IFDEF V23_ANSWER_MODE
F0_l equ f2100_l
F0_h equ f2100_h
F1_l equ f1300_l
F1_h equ f1300_h
;----------------------------------------------------
; *** Sample_rate/8 = 9600/8 = 75bps
;----------------------------------------------------
fsk_tx_baud_bit = 3 ;
ENDIF
IFDEF BELL202
F0_l equ f2100_l
F0_h equ f2100_h
F1_l equ f1300_l
F1_h equ f1300_h
;----------------------------------------------------
; *** Sample_rate/8 = 9600/8 = 75bps
;----------------------------------------------------
fsk_tx_baud_bit = 3 ;
ENDIF
IFDEF BELL103_ORIGINATE_MODE
F0_l equ f1070_l
F0_h equ f1070_h
F1_l equ f1270_l
F1_h equ f1270_h
;----------------------------------------------------
; *** Sample_rate/128 = 9600/32 = 300bps
;----------------------------------------------------
fsk_tx_baud_bit = 5 ;
ENDIF
IFDEF BELL103_ANSWER_MODE
F0_l equ f2025_l
F0_h equ f2025_h
F1_l equ f2225_l
F1_h equ f2225_h
;----------------------------------------------------
; *** Sample_rate/128 = 9600/32 = 300bps
;----------------------------------------------------
fsk_tx_baud_bit = 5 ;
ENDIF
;VP: Interrupt Setup.
;-------------------------------------------------------------------------------------
int_period equ 163 ; Gives an interrupt period at 50MHz of (163 * (1/50000000)s) = 3.26us
; Which gives an interrupt frequency of (1/3.26u)Hz = 306.75kHz
;-------------------------------------------------------------------------------------
IFDEF SX48_52
;*********************************************************************************
; SX48BD/52BD Mode addresses
; *On SX48BD/52BD, most registers addressed via mode are read and write, with the
; exception of CMP and WKPND which do an exchange with W.
;*********************************************************************************
; Timer (read) addresses
TCPL_R equ $02 ;Read Timer Capture register low byte
TCPH_R equ $02 ;Read Timer Capture register high byte
TR2CML_R equ $02 ;Read Timer R2 low byte
TR2CMH_R equ $03 ;Read Timer R2 high byte
TR1CML_R equ $04 ;Read Timer R1 low byte
TR1CMH_R equ $05 ;Read Timer R1 high byte
TCNTB_R equ $06 ;Read Timer control register B
TCNTA_R equ $07 ;Read Timer control register A
; Exchange addresses
CMP equ $08 ;Exchange Comparator enable/status register with W
WKPND equ $09 ;Exchange MIWU/RB Interrupts pending with W
; Port setup (read) addresses
WKED_R equ $0A ;Read MIWU/RB Interrupt edge setup, 0 = falling, 1 = rising
WKEN_R equ $0B ;Read MIWU/RB Interrupt edge setup, 0 = enabled, 1 = disabled
ST_R equ $0C ;Read Port Schmitt Trigger setup, 0 = enabled, 1 = disabled
LVL_R equ $0D ;Read Port Schmitt Trigger setup, 0 = enabled, 1 = disabled
PLP_R equ $0E ;Read Port Schmitt Trigger setup, 0 = enabled, 1 = disabled
DDIR_R equ $0F ;Read Port Direction
; Timer (write) addresses
TR2CML_W equ $12 ;Write Timer R2 low byte
TR2CMH_W equ $13 ;Write Timer R2 high byte
TR1CML_W equ $14 ;Write Timer R1 low byte
TR1CMH_W equ $15 ;Write Timer R1 high byte
TCNTB_W equ $16 ;Write Timer control register B
TCNTA_W equ $17 ;Write Timer control register A
; Port setup (write) addresses
WKED_W equ $1A ;Write MIWU/RB Interrupt edge setup, 0 = falling, 1 = rising
WKEN_W equ $1B ;Write MIWU/RB Interrupt edge setup, 0 = enabled, 1 = disabled
ST_W equ $1C ;Write Port Schmitt Trigger setup, 0 = enabled, 1 = disabled
LVL_W equ $1D ;Write Port Schmitt Trigger setup, 0 = enabled, 1 = disabled
PLP_W equ $1E ;Write Port Schmitt Trigger setup, 0 = enabled, 1 = disabled
DDIR_W equ $1F ;Write Port Direction
ELSE
;*********************************************************************************
; SX18AC/20AC/28AC Mode addresses
; *On SX18/20/28, all registers addressed via mode are write only, with the exception of
; CMP and WKPND which do an exchange with W.
;*********************************************************************************
; Exchange addresses
CMP equ $08 ;Exchange Comparator enable/status register with W
WKPND equ $09 ;Exchange MIWU/RB Interrupts pending with W
; Port setup (read) addresses
WKED_W equ $0A ;Write MIWU/RB Interrupt edge setup, 0 = falling, 1 = rising
WKEN_W equ $0B ;Write MIWU/RB Interrupt edge setup, 0 = enabled, 1 = disabled
ST_W equ $0C ;Write Port Schmitt Trigger setup, 0 = enabled, 1 = disabled
LVL_W equ $0D ;Write Port Schmitt Trigger setup, 0 = enabled, 1 = disabled
PLP_W equ $0E ;Write Port Schmitt Trigger setup, 0 = enabled, 1 = disabled
DDIR_W equ $0F ;Write Port Direction
ENDIF
;*****************************************************************************************
; Program memory ORG defines
;*****************************************************************************************
INTERRUPT_ORG equ $0 ; Interrupt must always start at location zero
RESET_ENTRY_ORG equ $1FB ; The program will jump here on reset.
MAIN_PROGRAM_ORG equ $600 ; The main program is in the last page of program memory.
;****************************** Beginning of program space *******************************
;*****************************************************************************************
;*****************************************************************************************
;*****************************************************************************************
org INTERRUPT_ORG ; First location in program memory.
;------------------------------------------------------------------------------
; Interrupt Service Routine
;------------------------------------------------------------------------------
; Note: The interrupt code must always originate at address $0.
;
; Interrupt Frequency = (Cycle Frequency / -(retiw value)) For example:
; With a retiw value of -163 and an oscillator frequency of 50MHz, this
; code runs every 3.26us.
;------------------------------------------------------------------------------
ISR ;3 The interrupt service routine...
;VP: PDM D/A Conversion
PDM_output
;------------------------------------------------------------------------------
; Virtual Peripheral: Jitter-Free, Deterministic Pulse Density Modulation
;
; Input variable(s): PDM0_out: Value from 0 - 255 corresponding to DC
; voltage
; Output variable(s): Ra.0 pin is PDM output pin
; Variable(s) affected: PDM0_acc variable
; Flag(s) affected: None
; Program Cycles: 11 cycles (turbo mode)
;------------------------------------------------------------------------------
_bank PDM_bank ;1 ; Update the PDM pin
add PDM0_acc,PDM0_out ;2,3 ; set PDM pin if carry
snc ;1,4
jmp :set_pin ;1,5 or 3,7 (carry)
:clear_pin
nop ;1,6 ; clear PDM pin (no carry)
nop ;1,7
clrb PDM_pin ;1,8
jmp :PDM_out ;3,11
:set_pin ;7 ; set PDM pin (carry)
setb PDM_pin ;1,8
jmp :PDM_out ;3,11
:PDM_out ; 11 PDM cycles total.
;------------------------------------------------------------------------------
; TOTAL CYCLE COUNT: 14
;------------------------------------------------------------------------------
;------------------------------------------------------------------------------
; Virtual Peripheral: Artificial Sine Wave Generation
;
; Input variable(s): freq_count_l, freq_count_h
; Output variable(s): sin,w returned as current value of sine
; wave.
; Variable(s) affected: freq_acc_high, freq_acc_low, sinvel, sin
; Flag(s) affected: None
; Program Cycles: 20 cycles worst case(turbo mode)
; Variable Length?: Yes
;------------------------------------------------------------------------------
_bank sin_gen_bank ;1
mov w,freq_count_low;1
add freq_acc_low,w ;1 ;advance sine at frequency
sc ;1
jmp :no_carry ;1,3 ; if lower byte rolls over
inc freq_acc_high ;1 ; carry over to upper byte
sz ;1
jmp :no_carry ;1,3 ; if carry causes roll-over
mov w,freq_count_high;1
mov freq_acc_high,w ;1 ; then add freq counter to accumulator (which should be zero,
; so move will work)
; and update sine wave
jmp :change_sin ;3
:no_carry
mov w,freq_count_high;1
add freq_acc_high,w ;1 ; add the upper bytes of the accumulators
sc ;1
jmp :no_change ;1,14
:change_sin
; 14 cycles at this point
mov w,++sinvel ;1 ; if the velocity of sine
sb sin.7 ;1 ; is positive, accelerate
mov w,--sinvel ;1 ; it. Otherwise, decelerate it.
mov sinvel,w ;1
add sin,w ;1,19 ; add the velocity to sin
:no_change
sine_generator_out
mov w,sin ;1,20 cycles worst case
;------------------------------------------------------------------------------
; TOTAL CYCLE COUNT: 14 + 20wc = 34 cycles worst case
;------------------------------------------------------------------------------
_bank PDM_bank ;1
mov PDM0_out,w ;1 ; mov the value of SIN into the PDM output
mov w,#128 ;1
add PDM0_out,w ;1 add 128 to put it in the center of the PDM output
;------------------------------------------------------------------------------
ISR_out ; ISR goes here when finished.
;------------------------------------------------------------------------------
isr_end ;3
mov w,#-int_period ;1 ; refresh RTCC on return
retiw ;3,7 ; return from the interrupt
; ; = 1/(int_period*RTCC prescaler*1/50MHz)
; ; = 1/(163*1*20ns) = 3.26us
;*****************************************************************************************
; End of the Interrupt Service Routine
;*****************************************************************************************
;*****************************************************************************************
;*****************************************************************************************
;*****************************************************************************************
;*****************************************************************************************
;*****************************************************************************************
;*****************************************************************************************
org RESET_ENTRY_ORG
;*****************************************************************************************
;------------------------------------------------------------------------------
reset_entry ; Program starts here on power-up
page _reset_entry
jmp _reset_entry
;------------------------------------------------------------------------------
;*****************************************************************************************
org MAIN_PROGRAM_ORG
;*****************************************************************************************
;*****************************************************************************************
; RESET VECTOR
;*****************************************************************************************
;*********************************************************************************
; Program execution begins here on power-up or after a reset
;*********************************************************************************
_reset_entry
;*********************************************************************************
; Initialise all port configuration
;*********************************************************************************
_mode ST_W ;point MODE to write ST register
mov w,#RB_ST ;Setup RB Schmitt Trigger, 0 = enabled, 1 = disabled
mov !rb,w
mov w,#RC_ST ;Setup RC Schmitt Trigger, 0 = enabled, 1 = disabled
mov !rc,w
IFDEF SX48_52
mov w,#RD_ST ;Setup RD Schmitt Trigger, 0 = enabled, 1 = disabled
mov !rd,w
mov w,#RE_ST ;Setup RE Schmitt Trigger, 0 = enabled, 1 = disabled
mov !re,w
ENDIF
_mode LVL_W ;point MODE to write LVL register
mov w,#RA_LVL ;Setup RA CMOS or TTL levels, 0 = TTL, 1 = CMOS
mov !ra,w
mov w,#RB_LVL ;Setup RB CMOS or TTL levels, 0 = TTL, 1 = CMOS
mov !rb,w
mov w,#RC_LVL ;Setup RC CMOS or TTL levels, 0 = TTL, 1 = CMOS
mov !rc,w
IFDEF SX48_52
mov w,#RD_LVL ;Setup RD CMOS or TTL levels, 0 = TTL, 1 = CMOS
mov !rd,w
mov w,#RE_LVL ;Setup RE CMOS or TTL levels, 0 = TTL, 1 = CMOS
mov !re,w
ENDIF
_mode PLP_W ;point MODE to write PLP register
mov w,#RA_PLP ;Setup RA Weak Pull-up, 0 = enabled, 1 = disabled
mov !ra,w
mov w,#RB_PLP ;Setup RB Weak Pull-up, 0 = enabled, 1 = disabled
mov !rb,w
mov w,#RC_PLP ;Setup RC Weak Pull-up, 0 = enabled, 1 = disabled
mov !rc,w
IFDEF SX48_52
mov w,#RD_PLP ;Setup RD Weak Pull-up, 0 = enabled, 1 = disabled
mov !rd,w
mov w,#RE_PLP ;Setup RE Weak Pull-up, 0 = enabled, 1 = disabled
mov !re,w
ENDIF
_mode DDIR_W ;point MODE to write DDIR register
mov w,#RA_DDIR ;Setup RA Direction register, 0 = output, 1 = input
mov !ra,w
mov w,#RB_DDIR ;Setup RB Direction register, 0 = output, 1 = input
mov !rb,w
mov w,#RC_DDIR ;Setup RC Direction register, 0 = output, 1 = input
mov !rc,w
IFDEF SX48_52
mov w,#RD_DDIR ;Setup RD Direction register, 0 = output, 1 = input
mov !rd,w
mov w,#RE_DDIR ;Setup RE Direction register, 0 = output, 1 = input
mov !re,w
ENDIF
mov w,#RA_latch ;Initialize RA data latch
mov ra,w
mov w,#RB_latch ;Initialize RB data latch
mov rb,w
mov w,#RC_latch ;Initialize RC data latch
mov rc,w
IFDEF SX48_52
mov w,#RD_latch ;Initialize RD data latch
mov rd,w
mov w,#RE_latch ;Initialize RE data latch
mov re,w
ENDIF
;*********************************************************************************
; Clear all Data RAM locations
;*********************************************************************************
zero_ram
IFDEF SX48_52 ;SX48/52 RAM clear routine
mov w,#$0a ;reset all ram starting at $0A
mov fsr,w
:zero_ram clr ind ;clear using indirect addressing
incsz fsr ;repeat until done
jmp :zero_ram
_bank bank0 ;clear bank 0 registers
clr $10
clr $11
clr $12
clr $13
clr $14
clr $15
clr $16
clr $17
clr $18
clr $19
clr $1a
clr $1b
clr $1c
clr $1d
clr $1e
clr $1f
ELSE ;SX18/20/28 RAM clear routine
clr fsr ;reset all ram banks
:zero_ram sb fsr.4 ;are we on low half of bank?
setb fsr.3 ;If so, don't touch regs 0-7
clr ind ;clear using indirect addressing
incsz fsr ;repeat until done
jmp :zero_ram
ENDIF
;*********************************************************************************
; Initialize program/VP registers
;*********************************************************************************
;*********************************************************************************
; Setup and enable RTCC interrupt, WREG register, RTCC/WDT prescaler
;*********************************************************************************
RTCC_ON = %10000000 ;Enables RTCC at address $01 (RTW hi)
;*WREG at address $01 (RTW lo) by default
RTCC_ID = %01000000 ;Disables RTCC edge interrupt (RTE_IE hi)
;*RTCC edge interrupt (RTE_IE lo) enabled by default
RTCC_INC_EXT = %00100000 ;Sets RTCC increment on RTCC pin transition (RTS hi)
;*RTCC increment on internal instruction (RTS lo) is default
RTCC_FE = %00010000 ;Sets RTCC to increment on falling edge (RTE_ES hi)
;*RTCC to increment on rising edge (RTE_ES lo) is default
RTCC_PS_ON = %00000000 ;Assigns prescaler to RTCC (PSA lo)
RTCC_PS_OFF = %00001000 ;Assigns prescaler to WDT (PSA lo)
PS_000 = %00000000 ;RTCC = 1:2, WDT = 1:1
PS_001 = %00000001 ;RTCC = 1:4, WDT = 1:2
PS_010 = %00000010 ;RTCC = 1:8, WDT = 1:4
PS_011 = %00000011 ;RTCC = 1:16, WDT = 1:8
PS_100 = %00000100 ;RTCC = 1:32, WDT = 1:16
PS_101 = %00000101 ;RTCC = 1:64, WDT = 1:32
PS_110 = %00000110 ;RTCC = 1:128, WDT = 1:64
PS_111 = %00000111 ;RTCC = 1:256, WDT = 1:128
OPTIONSETUP equ RTCC_PS_OFF|PS_111 ; the default option setup for this program.
jmp @main
;*****************************************************************************************
; MAIN PROGRAM CODE
;*****************************************************************************************
;*********************************************************************************
; Main
;*********************************************************************************
main
_bank sin_gen_bank
; mov sin,#32 ; init variables. A sine starts at 1, a cos wave starts at 0.
; mov sinvel,#0
mov sin,#-4 ; use these values for a wave which is 90 degrees out of phase.
mov sinvel,#-8
clrb CTS ; enable transmission from the PC if hardware flow
; control is enabled.
mov w,#OPTIONSETUP ; setup option register for RTCC interrupts enabled
mov !option,w ; and no prescaler.
_bank sin_gen_bank
mov freq_count_high,#f2100_h; output a frequency of 2100Hz
mov freq_count_low,#f2100_l ; (bell202)
clrb hook ; go off-hook
jb rx_pin,$ ; wait until data is received (Start bit is a low)
mov w,#OPTIONSETUP ; setup option register for RTCC interrupts enabled
mov !option,w ; and no prescaler.
clrb hook ; go off-hook
main_loop
jb rx_pin,:rx_is_high ; If the rs_232 receive pin is currently a low
:rx_is_low clrb led_pin ; Turn the LED on
clrb tx_pin ; Echo the character
mov freq_count_high,#f0_h ; output a frequency of 2100Hz
mov freq_count_low,#f0_l ; (bell202)
jmp main_loop
:rx_is_high setb led_pin ; Else turn the LED off
setb tx_pin ; turn Echo the character
mov freq_count_high,#f1_h ; output a frequency of 1300Hz
mov freq_count_low,#f1_l ; (bell202)
jmp main_loop
;*****************************************************************************************
END ;End of program code
;*****************************************************************************************
;*****************************************************************************************
;*****************************************************************************************
;*****************************************************************************************
;*****************************************************************************************
;*****************************************************************************************
;*****************************************************************************************
| file: /Techref/scenix/lib/io/dev/modem/simple_fsk_gen_1_03.SRC, 38KB, , updated: 2002/4/11 12:05, local time: 2024/11/14 17:52,
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