; ****************************************************************************** ; Copyright © [01/25/1999] 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regarding (e.g.: application, ; implementation) and the like is intended through suggestion only and may ; be superseded by updates.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. ;****************************************************************************** ; ; Filename: bell_103_tx.src ; ; Author: Chris Fogelklou ; Applications Engineer ; Scenix Semiconductor Inc. ; ; Revision: 1.08 ; ; Date: April 16, 1999. ; ; Part: SX28AC rev. 2.5 ; ; Freq: 50Mhz ; ; Compiled using Parallax SX-Key software v1.0 ; ; Version: 1.10 ; ; Program Description: This simple program encodes an outgoing bell103 signal. ; This program only creates the answer frequencies, since it ; cannot dial out to originate. ; ; To use this program, connect the SX-DTMF-DEMO board to a phone ; line and to a PC. The communications settings are 300,N,8,1. ; Now, from a remote BELL103 modem, simply dial the modem's number. ; When you here the line ringing on the dialing modem, press a key ; in the comm window of the SX-modem-board. This should force the ; modem board off-hook and cause it to send out an answer tone for ; 3 seconds. Once the answer tone is sent, the modem board will ; begin modulating the state of the RS-232 pin onto the carrier. ; If the terminal program is set up correctly, you will be able to ; receive the sent characters on the remote modem. ; ; Revision History: 1.0 Tried for weeks to get FSK-receive to work. Finally got it ; working. ; 1.01 Tried to eliminate all unnecessary code... ; 1.04 Originate and answer modes both working. AT command set added. ; 1.10 Changed the fsk receive code so it is simpler to understand and ; uses less RAM. ; ; INPUTS: ; Received RS-232 characters on rs-232 rx_pin (ra.1) ; OUTPUTS: ; Received RS-232 characters on tx_pin (ra.2) ; FSK output on PPM_pin ; LED flashes (rb.0) ; ; RESOURCES: ; Program memory: TBD ; Data memory: TBD ; I/O Count: TBD ; ;****************************************************************************** ; Device Directives ;****************************************************************************** SX28L_compiler IFDEF SX28L_compiler device SX28L,oscxt4,carryx ; 28-pin device, 4 pages, 8 banks of RAM device turbo,stackx_optionx ; High speed oscillator, turbo mode, ; option register extend, 8-level stack ELSE device pins28,pages4,banks8,carryx ; 28-pin device, 1 pages, 8 banks of RAM device oschs,turbo,optionx,stackx ; High speed oscillator, turbo mode, ENDIF ; option register extend, 8-level stack freq 50_000_000 ; default run speed = 50MHz ID 'B103TX10' ; Version = 1.0 reset reset_entry ; JUMP to reset_entry label on reset ;****************************************************************************** ; Watches (For Debug in SX_Key software V.1.0 +) ;****************************************************************************** watch fsk_answering,1,ubin watch freq_acc_low,16,udec watch freq_count_low,16,udec watch sine_index,8,udec watch D_to_A_val,8,udec watch freq_acc_high,16,uhex watch freq_count_high,8,uhex watch freq_count_low,8,uhex watch freq_count_high2,8,uhex watch freq_count_low2,8,uhex watch byte,1,fstr watch byte,8,udec watch curr_sine,8,sdec watch sine_index,8,sdec watch D_to_A_val,8,udec watch PPM0_acc,8,udec watch timer_flag,1,ubin watch timer_l,16,uhex watch temp,8,uhex watch wreg,8,uhex watch fsk_last_trans,8,udec watch fsk_trans_avg_l,16,udec watch fsk_avg_count,8,udec watch fsk_trans_count,8,udec watch fsk_glitch_acc,8,udec watch fsk_high_byte,8,udec watch fsk_average_index,8,udec watch fsk_temp_trans,8,udec watch fsk_processing_required1,1,ubin watch fsk_processing_required2,1,ubin watch fsk_carrier_detected,1,ubin watch fsk_rb_past_state,8,ubin ;************************************************************************** ; Equates for common data comm frequencies ;************************************************************************** f697_h equ $012 ; DTMF Frequency f697_l equ $09d f770_h equ $014 ; DTMF Frequency f770_l equ $090 f852_h equ $016 ; DTMF Frequency f852_l equ $0c0 f941_h equ $019 ; DTMF Frequency f941_l equ $021 f1209_h equ $020 ; DTMF Frequency f1209_l equ $049 f1336_h equ $023 ; DTMF Frequency f1336_l equ $0ad f1477_h equ $027 ; DTMF Frequency f1477_l equ $071 f1633_h equ $02b ; DTMF Frequency f1633_l equ $09c ;****************************************************************************** ; Equates for FSK generation ;****************************************************************************** f2225_h equ $03b f2225_l equ $06b f2025_h equ $036 f2025_l equ $014 f1070_h equ $01c f1070_l equ $093 f1270_h equ $021 f1270_l equ $0ea f2100_h equ $038 ; 2100Hz Signifies LOW data in Bell202 Spec f2100_l equ $015 ;************************************************************************** ; Equates for certain baud rates: ;************************************************************************** ;baud_bit = 4 ;for 19200 baud ;start_delay = 16+8+1 ; " " " ;int_period = 163 ; " " " ; *** 2400 baud (for slower baud rates, increase the RTCC prescaler) baud_bit = 7 ;for 2400 baud start_delay = 128+64+1 ; " " " fsk_start_delay = 128+96+1 int_period = 163 ; " " " ;****************************************************************************** ; Pin Definitions (These definitions are for SX DTMF DEMO boards) ;****************************************************************************** PPM_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_dir_mask equ %11111010 ; sets up the I/O directions of port ra ra_data_mask equ %11111111 ; sets up the output levels of the output pins on ra 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_dir_mask equ %01101110 ; sets up the I/O directions of port rb rb_data_mask equ %01011011 ; sets up the output levels of the output pins on ra LPF_mask equ %01001110 ; when LPF is enabled, tristate cntrl 1 and put cntrl 3 low HPF_mask equ %01101010 ; when HPF is enabled, tristate cntrl 3 and put cntrl 1 low LPF_HPF_mask equ %01101110 ; when both filters are enabled, tristate cntrl 1 and cntrl 3 dtmf_in_pin equ rc.0 dtmf_fdbk_pin equ rc.1 AtoD_in_pin equ rc.2 AtoD_fdbk_pin equ rc.3 imp_450_pin equ rc.4 imp_600_pin equ rc.5 imp_750_pin equ rc.6 imp_900_pin equ rc.7 rc_dir_mask equ %11010101 ; sets up the I/O directions of port rc rc_data_mask equ %00001111 ; sets up the output levels of the output pins on ra ;****************************************************************************** ; Global Variables ;****************************************************************************** org $8 ; Global registers flags ds 1 dtmf_gen_en equ flags.0 ; Signifies whether or not DTMF output is enabled sine_gen_en equ flags.1 timer_flag equ flags.2 fsk_tx_en equ flags.3 fsk_rx_en equ flags.4 ; Enables the FSK receiver. rx_flag equ flags.5 fsk_rx_flag equ flags.6 temp ds 1 task_switcher ds 1 ascii_index ds 1 command_index ds 1 ;****************************************************************************** ; Bank 0 Variables ;****************************************************************************** org $10 sine_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 sine_index ds 1 sine_index2 ds 1 ; The velocity of the sin wave freq_count_low2 ds 1 ; 16-bit counter which decides which frequency for the sine wave freq_count_high2 ds 1 ; freq_count = Frequency * 6.83671552 freq_acc_high2 ds 1 ; freq_acc_low2 ds 1 ; 16-bit accumulator which decides when to increment the sine wave curr_sine ds 1 ; The current value of the imitation sin wave curr_sine2 ds 1 ; The current value of the imitation sin wave sine2_temp ds 1 ; This register is used to do a temporary shift/add register PPM_bank = $ PPM0_acc ds 1 ; PPM accumulator D_to_A_val ds 1 ; current PPM output ;****************************************************************************** ; Bank 1 Variables ;****************************************************************************** org $30 timers = $ timer_l ds 1 timer_h ds 1 timer_hh ds 1 serial = $ ;UART bank tx_high ds 1 ;hi byte to transmit tx_low ds 1 ;low byte to transmit tx_count ds 1 ;number of bits sent tx_divide ds 1 ;xmit timing (/16) counter rx_count ds 1 ;number of bits received rx_divide ds 1 ;receive timing counter rx_byte ds 1 ;buffer for incoming byte rx_count2 ds 1 ;number of bits received rx_divide2 ds 1 ;receive timing counter rx_byte2 ds 1 ;buffer for incoming byte string ds 1 byte ds 1 plus_count ds 1 ;****************************************************************************** ; Bank 2 Variables ;****************************************************************************** org $50 ;bank3 variables fsk_receive_bank = $ fsk_transmit_bank = $ fsk_last_trans ds 1 fsk_trans_avg_l ds 1 fsk_trans_avg_h ds 1 fsk_avg_count ds 1 fsk_trans_count ds 1 ; This register counts the number of counts ; between transitions at the pin fsk_rb_past_state ds 1 ; This register keeps track of the previous ; state of port RB, to watch for transitions fsk_glitch_acc ds 1 fsk_average ds 1 fsk_high_byte ds 1 fsk_average_index ds 1 fsk_temp_trans ds 1 fsk_no_carrier_count ds 1 fsk_flags ds 1 fsk_answering equ fsk_flags.0 fsk_tx_bit equ fsk_flags.1 fsk_rx_bit equ fsk_flags.2 fsk_processing_required1 equ fsk_flags.3 fsk_processing_required2 equ fsk_flags.4 fsk_rx_bit_last equ fsk_flags.5 fsk_carrier_detected equ fsk_flags.6 fsk_answer_tone equ fsk_flags.7 ;************************************************************* ; Bank 4, 5, 6, 7 (for ascii buffer, but can be reused.) ;************************************************************* org $90 ascii_buffer = $ org $b0 ascii_buffer2 = $ org $d0 ascii_buffer3 = $ org $f0 ascii_buffer4 = $ ;************************ Beginning of program space *************************** ;****************************************************************************** ; Interrupt org $0 ; The interrupt Service routine starts at location zero. ; ; With a retiw value of -163 and an oscillator frequency of 50MHz, this ; code runs every 3.26us. ;****************************************************************************** PPM_output bank PPM_bank ; Update the PPM pin clc add PPM0_acc,D_to_A_val snc setb PPM_pin sc clrb PPM_pin ;****************************************************************************** FSK_output jnb dtmf_gen_en,:dtmf_disabled call @sine_generator1 jmp :task_switcher :dtmf_disabled snb sine_gen_en ; Output the frequencies set by the freq_count registers call @sine_generator2 snb fsk_rx_en call @fsk_receive :task_switcher inc task_switcher mov w,task_switcher and w,#$07 clc jmp pc+w jmp :fsk_process_1 ;0 jmp :fsk_process_2 ;1 jmp :fsk_process_3 ;2 jmp :fsk_transmit ;3 jmp :fsk_get_carrier;4 jmp do_timers ;5 jmp :transmit ;6 jmp :receive ;7 :fsk_process_1 call @FSK_RECEIVE_PROCESSING1 jmp do_timers :fsk_process_2 call @FSK_RECEIVE_PROCESSING2 jmp do_timers :fsk_process_3 call @FSK_RECEIVE_PROCESSING3 jmp do_timers :fsk_transmit snb fsk_tx_en call @TRANSMIT_FSK ; into its corresponding frequencies jmp do_timers :fsk_get_carrier call @FSK_GET_CARRIER jmp do_timers ;************************************************************************** :transmit ; This is an asynchronous RS-232 transmitter ; INPUTS: ; tx_divide.baud_bit - Transmitter only executes when this bit is = 1 ; tx_high - Part of the data to be transmitted ; tx_low - Some more of the data to be transmitted ; tx_count - Counter which counts the number of bits transmitted. ; OUTPUTS: ; tx_pin - Sets/Clears this pin to accomplish the transmission. ;************************************************************************** bank serial clrb tx_divide.baud_bit ;clear xmit timing count flag inc tx_divide ;only execute the transmit routine STZ ;set zero flag for test SNB tx_divide.baud_bit ; every 2^baud_bit interrupt test tx_count ;are we sending? JZ do_timers ;if not, go to :receive clc ;yes, ready stop bit rr tx_high ; and shift to next bit rr tx_low ; dec tx_count ;decrement bit counter movb tx_pin,/tx_low.6 ;output next bit jmp do_timers ;************************************************************************** :receive ; This is an asynchronous receiver for RS-232 reception ; INPUTS: ; rx_pin - Pin which RS-232 is received on. ; OUTPUTS: ; rx_byte - The byte received ; rx_flag - Set when a byte is received. ;************************************************************************** bank serial movb c,rx_pin ;get current rx bit test rx_count ;currently receiving byte? jnz :rxbit ;if so, jump ahead mov w,#9 ;in case start, ready 9 bits sc ;skip ahead if not start bit mov rx_count,w ;it is, so renew bit count mov rx_divide,#start_delay ;ready 1.5 bit periods :rxbit djnz rx_divide,:rxdone ;middle of next bit? setb rx_divide.baud_bit ;yes, ready 1 bit period dec rx_count ;last bit? sz ;if not rr rx_byte ; then save bit snz ;if so setb rx_flag ; then set flag :rxdone ;************************************************************************** do_timers bank timers ; Update the timers inc timer_l snz inc timer_h snz setb timer_flag snz inc timer_hh setb led_pin sb timer_h.6 clrb led_pin ;****************************************************************************** :ISR_DONE ; This is the end of the interrupt service routine. Now load 163 into w and ; perform a retiw to interrupt 163 cycles from the start of this one. ; (3.26us@50MHz) ;****************************************************************************** mov w,#-163 ;1 ; interrupt 163 cycles after this interrupt retiw ;3 ; return from the interrupt ;****************************************************************************** ; End of the Interrupt Service Routine ;****************************************************************************** ;************************************************************************** time_n_ticks ; This subroutine times 'w' ticks, and returns with a '1' in w when ; the specified time has timed out. Each tick is 213.647 ms. ; This subroutine uses the TEMP register ; INPUT w - # of milliseconds to delay for. ; OUTPUT Returns after n milliseconds. ;************************************************************************** bank timers test wreg jz :check_time clc add w,timer_hh mov temp,w retw 0 :check_time mov w,temp xor w,timer_hh sz retw 0 retw 1 ;****************************************************************************** reset_entry ; Program Starts Here on Power Up ;****************************************************************************** call @init mov !option,#%00011111 ; enable wreg and rtcc interrupt mov w,#_hello call @send_string main_2 _send_prompt mov w,#_CR call @send_string mov w,#_prompt ; send prompt call @send_string _cmd_loop jnb rx_flag,$ clrb rx_flag bank serial mov byte,rx_byte call @uppercase ; convert it to uppercase stc cje byte,#$20,_cmd_loop ; if it equals a space, ignore it. stc cje byte,#$0d,:enter ; if it equals a carriage return, parse the string. mov w,byte ; if it does not resemble the above characters, echo it. call @send_byte stc cje byte,#$08,:backspace ; if it equals a backspace, delete one character in the buffer. call @buffer_push ; otherwise, store it jmp _cmd_loop ; and come back for more. :backspace call @buffer_backspace jmp _cmd_loop :enter ; If the user presses enter, then parse the string. ;************************************************************************** ; String parser (Checks to see if buffer = any commands) ; -Checks contents of ascii buffer against any commands stored in ROM ; -If a command = the contents of the ascii buffer, a routine will be called ; -Each routine MUST perform a retw 0 on exit, or parse_string will not ; know that a routine has run and it should exit back to command mode. ; -Exits back to command mode when it detects a zero after the table look-up. ; -Outputs 'OK' if no commands are matched. ;************************************************************************** parse_string clr ascii_index ; Clear the index into the ascii buffer clr command_index ; And the index into the commands :loop call @buffer_get ; Get a vale from the buffer at ascii_index call command_table ; Get a character from one of the commands test wreg ; If the return value is 0, then this matched jz :nothing ; the command and ran a routine. Exit. bank serial xor w,byte ; compare the command's character with the jnz :not_equal ; buffer's character. call @inc_ascii_index ; Increment the index into the buffer. jmp :loop :not_equal inc command_index ; If the buffer did not equal the command, clr ascii_index ; start from the beginning of a new command stc cjne command_index,#6,:loop ; and the buffer. (This number = # of commands) :nothing mov w,#_CR call @send_string mov w,#_OK ; If we have checked all 4 commands, then this call @send_string ; did not equal any so send an 'OK' message. :done bank ascii_buffer clr ascii_index clr ascii_buffer jmp _send_prompt ;************************************************************************** command_table mov w,command_index clc add pc,w jmp command_1 jmp command_2 jmp command_3 jmp command_4 jmp command_5 jmp command_6 ;************************************************************************** command_1 ; Dial command mov w,ascii_index add PC,w retw 'A' retw 'T' retw 'D' retw 'T' jmp DIAL_MODE ;************************************************************************** command_2 ; Hang up command mov w,ascii_index add PC,w retw 'A' retw 'T' retw 'H' jmp HANG_UP ;************************************************************************** command_3 ; Initialize mov w,ascii_index add PC,w retw 'A' retw 'T' retw 'Z' jmp INITIALIZE ;************************************************************************** command_4 ; Answer/ Auto answer mov w,ascii_index add PC,w retw 'A' retw 'T' retw 'A' jmp AUTO_ANSWER ;************************************************************************** command_5 ; Data mode mov w,ascii_index add PC,w retw 'A' retw 'T' retw 'O' jmp FSK_IO ;************************************************************************** command_6 ; Help mov w,ascii_index add PC,w retw '?' jmp HELP ;************************************************************************** ; END of String parser (Checks to see if buffer = any commands) ;************************************************************************** HANG_UP setb hook retw 0 INITIALIZE call @init clr flags retw 0 AUTO_ANSWER jmp Answer retw 0 HELP retw 0 ;************************************************************************** ; Dial Mode: ; -Dials contents of ascii buffer, starting from location pointed ; to by ascii_index. ; -Responds to these commands: ; 0-9, *, # - Dials the specified number ; , - Pause for 2 seconds ; -Jumps to data mode after dialing. ;************************************************************************** DIAL_MODE mov w,#_CR call @send_string mov w,#_DIALING ; send Dialing call @send_string clrb hook mov w,#255 call @delay_10n_ms bank serial :dial_loop call @buffer_get ; wait for an input character call @uppercase ; convert it to uppercase mov w,byte snz jmp :originate_mode call @send_byte cje byte,#',',:pause ; if the character = ',', pause for 2s call @digit_2_index ; convert the ascii digit to an ; index value call @load_frequencies ; load the frequency registers call @dial_it ; dial the number for 60ms and return. :inc call @inc_ascii_index ; increment the index into the table jmp :dial_loop :pause mov w,#201 ; delay 2s call @delay_10n_ms jmp :inc :originate_mode ;****************************************************************** ; Go off-hook ;****************************************************************** mov m,#$0f mov !rb,#HPF_mask ; Enable HPF and disable LPF clrb cntrl_1 clr flags bank fsk_transmit_bank clrb fsk_answering setb fsk_rx_en setb fsk_tx_bit setb sine_gen_en setb fsk_tx_en mov w,#140 ; wait 30 seconds for answer_tone call time_n_ticks :loop ; clr w ; call time_n_ticks ; test wreg ; jnz no_carrier ; bank fsk_receive_bank ; jnb fsk_answer_tone,:loop jmp FSK_IO Answer clrb hook ; Go off-hook mov m,#$0f mov !rb,#LPF_mask ; Enable LPF and disable HPF clrb cntrl_3 call @answer_tone ; Send out the answer tone for 3 seconds bank fsk_transmit_bank ; Clear all the flags clr flags setb fsk_answering ; enable answering frequencies setb fsk_tx_bit ; Set the tx_bit to output a high frequency setb fsk_tx_en ; enable FSK transmit setb sine_gen_en ; enable sine generation mov w,#255 call @delay_10n_ms mov w,#255 call @delay_10n_ms bank fsk_receive_bank ; enable FSK receive setb fsk_rx_en FSK_IO mov w,#47 call time_n_ticks :loop clr w call time_n_ticks test wreg ; jnz no_carrier bank fsk_receive_bank ; jnb fsk_carrier_detected,:loop mov w,#_DATA_MODE call @send_string mov w,#_prompt call @send_string clr plus_count :loop2 bank fsk_receive_bank ; jnb fsk_carrier_detected,no_carrier movb fsk_tx_bit,rx_pin ; move the rs-232 pin to the fsk_tx_bit movb tx_pin,fsk_rx_bit ; and move the fsk_rx_bit to the rs-232 pin jb rx_flag,:check_for_plus jmp :loop2 ; jump here forever (ISR does all the work) :check_for_plus bank serial clrb rx_flag inc plus_count mov w,#'+' xor w,rx_byte sz clr plus_count mov w,#3 xor w,plus_count snz retw 0 jmp :loop2 no_carrier setb tx_pin mov w,#255 call @delay_10n_ms mov w,#_no_carrier call @send_string bank serial :loop test tx_count jz INITIALIZE jmp :loop org $200 ;****************************************************************************** FSK_RECEIVE ;************************************************************************** bank fsk_receive_bank ; switch to fsk_receive_bank of RAM inc fsk_trans_count ; Increment the transition count snz dec fsk_trans_count ; If the result is zero, keep fsk_trans_count in range clc mov w,fsk_rb_past_state ; Check for a transition xor w,rb and w,#%00000010 snz retp ; return if there has been no transition xor fsk_rb_past_state,w ; save the new value of the FSK_pin jb fsk_answering,:dont_double sb fsk_rb_past_state.1 retp :dont_double clc mov w,#-30 add w,fsk_trans_count jnc :glitch mov fsk_temp_trans,fsk_trans_count clc add fsk_trans_avg_l,w snc inc fsk_trans_avg_h inc fsk_avg_count clr fsk_trans_count setb fsk_processing_required1 retp :glitch ; Save any glitches in the glitch accumulator, to be added to ; the transition count before processing clc add fsk_glitch_acc,fsk_trans_count retp ;************************************************************************** FSK_RECEIVE_PROCESSING1 ; This code is not very speed critical and can ; run every so often in the ISR. ;************************************************************************** bank fsk_receive_bank sb fsk_processing_required1 retp clrb fsk_processing_required1 setb fsk_processing_required2 retp ;************************************************************************** FSK_RECEIVE_PROCESSING2 ; This code is not very speed critical and can ; run every so often in the ISR. ;************************************************************************** ;****************************************************************** ; If no processing is required, exit ;****************************************************************** bank fsk_receive_bank ;1 sb fsk_processing_required2 ;1 retp ;1 clrb fsk_processing_required2 ;1 ;****************************************************************** ; Add the last transition time to this one, and divide by two. ; and also add the glitch accumulator. ;****************************************************************** clc rr fsk_glitch_acc clc mov w,fsk_last_trans add w,fsk_temp_trans rr wreg clc add w,fsk_glitch_acc clr fsk_glitch_acc ;****************************************************************** ; Now compare the result to 130 for answer mode or to 145 for ; originate mode. Anything above this threshold is a "high" bit, ; and anything below this threshold is a "low" bit. ;****************************************************************** mov fsk_last_trans,w ;1 mov w,#-130 ;1 sb fsk_answering ;1 mov w,#-145 ;1 clc ;1 add w,fsk_last_trans ;1 setb fsk_rx_bit ;1 snc ;1 clrb fsk_rx_bit ;1;50 ;3;53 mov fsk_last_trans,fsk_temp_trans retp ;************************************************************************** FSK_RECEIVE_PROCESSING3 ;************************************************************************** retp bank fsk_receive_bank sb fsk_rx_bit jmp :rx_bit_low :rx_bit_high snb fsk_rx_bit_last retp setb fsk_rx_bit_last mov w,#121 sb fsk_answering mov w,#138 jmp :hysterises :rx_bit_low sb fsk_rx_bit_last retp clrb fsk_rx_bit_last mov w,#144 sb fsk_answering mov w,#152 :hysterises mov fsk_last_trans,w retp ;************************************************************************** FSK_GET_CARRIER ;************************************************************************** bank fsk_receive_bank mov w,fsk_avg_count sz retp inc fsk_avg_count clrb fsk_answer_tone clrb fsk_carrier_detected jb fsk_answering,:low_freqs mov w,#-135 clc add w,fsk_trans_avg_h jnc :get_answer_tone; If the average transition ; time is less than 138, error... mov w,#-152 clc add w,fsk_trans_avg_h sc setb fsk_carrier_detected :get_answer_tone mov w,#-142 clc add w,fsk_trans_avg_h jnc :no_answer_tone mov w,#-148 clc add w,fsk_trans_avg_h sc setb fsk_answer_tone :no_answer_tone clr fsk_trans_avg_h clr fsk_trans_avg_l retp :low_freqs mov w,#-118 clc add w,fsk_trans_avg_h jnc :no_carrier ; If the average transition ; time is less than 138, error... mov w,#-145 clc add w,fsk_trans_avg_h sc setb fsk_carrier_detected :no_carrier clr fsk_trans_avg_h clr fsk_trans_avg_l retp ;************************************************************************** TRANSMIT_FSK ;************************************************************************** bank fsk_transmit_bank jb fsk_answering,transmit_answer_tones transmit_originate_tones jnb fsk_tx_bit,:low_freq :high_freq bank sine_gen_bank mov freq_count_high2,#f1270_h mov freq_count_low2,#f1270_l retp :low_freq bank sine_gen_bank mov freq_count_high2,#f1070_h mov freq_count_low2,#f1070_l retp transmit_answer_tones jnb fsk_tx_bit,:low_freq :high_freq bank sine_gen_bank mov freq_count_high2,#f2225_h mov freq_count_low2,#f2225_l retp :low_freq bank sine_gen_bank mov freq_count_high2,#f2025_h mov freq_count_low2,#f2025_l retp ;************************************************************************** answer_tone ;************************************************************************** bank sine_gen_bank ; send out the answer tone for 3 seconds clr curr_sine mov freq_count_high2,#f2100_h mov freq_count_low2,#f2100_l setb sine_gen_en ; enable the FSK transmitter mov w,#255 call @delay_10n_ms mov w,#45 call @delay_10n_ms retp ;************************************************************************** org $300 ;************************************************************************** ; String data (for RS-232 output) and tables ;************************************************************************** _hello dw 13,10,'SX Modem V 4.0',13,10,0 _instructions dw '- ? For Help',0 _DIALING dw 'DIAL ',0 _ANSWERING dw 'ANSWERING ',0 _AUTO_ANSWER dw 'AUTO ANSWER ',13,10,0 _RING dw 'RING',13,10,0 _PROMPT dw 13,10,'>',0 _HANGING_UP dw 'HANG UP ',13,10,0 _ATDT dw 13,10,'ATDT=',0 _ATA dw 'ATA =',0 _ATH dw 'ATH =',0 _ATZ dw 'ATZ =',0 _ATO dw 'ATO =',0 _plus dw 13,10,'+++ =',0 _OK dw 'OK',13,10,0 _CR dw 13,10,0 _COMMAND_MODE dw 'COMMAND MODE',13,10,0 _DATA_MODE dw 13,10,'CONNECT 300',0 _no_carrier dw 13,10,'NO CARRIER',0 _INIT dw 'INIT',0 org $400 ; Miscellaneous subroutines ;************************************************************************** buffer_push ; This subroutine pushes the contents of byte onto the 32-byte ascii buffer. ;************************************************************************** bank serial ; Move the byte into the buffer mov temp,byte mov fsr,#ascii_buffer clc add fsr,ascii_index mov indf,temp ; Increment index and keep it in range call @inc_ascii_index mov fsr,#ascii_buffer ; Null terminate the buffer. clc add fsr,ascii_index clr indf bank serial retp ;************************************************************************** ;************************************************************************** buffer_backspace ; This subroutine deletes one value of the buffer and decrements the index ;************************************************************************** dec ascii_index and ascii_index,#%01101111 mov fsr,#ascii_buffer clc add fsr,ascii_index clr indf bank serial retp ;************************************************************************** inc_ascii_index ; This subroutine increments the index into the buffer ;************************************************************************** mov w,ascii_index and w,#%00001111 xor w,#%00001111 jnz :not_on_verge inc ascii_index mov w,#16 clc add w,ascii_index and w,#$7f mov ascii_index,w retp :not_on_verge inc ascii_index retp ;************************************************************************** buffer_get ; This subroutine retrieves the buffered value at index ;************************************************************************** mov fsr,#ascii_buffer clc add fsr,ascii_index mov w,indf bank serial mov byte,w retp ;************************************************************************** delay_10n_ms ; This subroutine delays 'w'*10 milliseconds. ; This subroutine uses the TEMP register ; INPUT w - # of milliseconds to delay for. ; OUTPUT Returns after 10 * n milliseconds. ;************************************************************************** mov temp,w bank timers :loop clrb timer_flag ; This loop delays for 10ms mov timer_h,#$0f4 mov timer_l,#$004 jnb timer_flag,$ dec temp ; do it w-1 times. jnz :loop clrb timer_flag retp ;************************************************************************** delay_n_ms ; This subroutine delays 'w' milliseconds. ; This subroutine uses the TEMP register ; INPUT w - # of milliseconds to delay for. ; OUTPUT Returns after n milliseconds. ;************************************************************************** mov temp,w bank timers :loop clrb timer_flag ; This loop delays for 1ms mov timer_h,#$0fe mov timer_l,#$0cd jnb timer_flag,$ dec temp ; do it w-1 times. jnz :loop clrb timer_flag retp ;************************************************************************** zero_ram ; Subroutine - Zero all ram. ; INPUTS: None ; OUTPUTS: All ram locations (except special function registers) are = 0 ;************************************************************************** CLR FSR :loop 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 IJNZ FSR,:loop ;repeat until done retp ;************************************************************************** init ;************************************************************************** mov m,#$0d mov !ra,#$00 ; initialize all ports to CMOS levels mov !rb,#$00 mov !rc,#$00 mov m,#$0f ; initialize the ports mov !ra,#ra_dir_mask mov ra,#ra_data_mask mov !rb,#rb_dir_mask mov rb,#rb_data_mask mov !rc,#rc_dir_mask mov rc,#rc_data_mask setb hook ; go on hook. setb led_pin ; turn on LED clr flags ; Clear all flags call zero_ram retp ;************************************************************************** ; Subroutine - Get byte via serial port and echo it back to the serial port ; INPUTS: ; -NONE ; OUTPUTS: ; -received byte in rx_byte ;************************************************************************** get_byte jnb rx_flag,$ ;wait till byte is received clrb rx_flag ;reset the receive flag bank serial mov byte,rx_byte ;store byte (copy using W) ; & fall through to echo char back ;************************************************************************** ; Subroutine - Send byte via serial port ; INPUTS: ; w - The byte to be sent via RS-232 ;************************************************************************** send_byte bank serial :wait test tx_count ;wait for not busy jnz :wait ; not w ;ready bits (inverse logic) mov tx_high,w ; store data byte setb tx_low.7 ; set up start bit mov tx_count,#10 ;1 start + 8 data + 1 stop bit RETP ;leave and fix page bits ;************************************************************************** ; Subroutine - Send string pointed to by address in W register ; INPUTS: ; w - The address of a null-terminated string in program ; memory ; OUTPUTS: ; outputs the string via. RS-232 ;************************************************************************** send_string bank serial mov string,w ;store string address :loop mov w,string ;read next string character mov m,#3 ; with indirect addressing iread ; using the mode register mov m,#$F ;reset the mode register test w ;are we at the last char? snz ;if not=0, skip ahead RETP ;yes, leave & fix page bits call send_byte ;not 0, so send character inc string ;point to next character jmp :loop ;loop until done ;************************************************************************** ; Subroutine - Make byte uppercase ; INPUTS: ; byte - The byte to be converted ; OUTPUTS: ; byte - The uppercase byte ;************************************************************************** uppercase stc csae byte,#'a' ;if byte is lowercase, then skip ahead RETP stc sub byte,#'a'-'A' ;change byte to uppercase RETP ;leave and fix page bits ;************************************************************************** ; Subroutine - Disable the outputs ; Load DC value into PPM and disable the output switch. ;************************************************************************** disable_o bank PPM_bank ; input mode. mov D_to_A_val,#128 ; put 2.5V DC on PPM output pin retp ;************************************************************************** org $600 ; These subroutines are on page 3. ;************************************************************************** ; DTMF transmit functions/subroutines ;************************************************************************** ;************************************************************************** DTMF_TABLE ; DTMF tone constants ; This routine returns with the constant used for each of the frequency ; detectors. ; INPUT: w - Index into the table (0-15 value) ; OUTPUT: w - Constant at that index ;************************************************************************** clc jmp PC+w retw f697_l retw f697_h retw f770_l retw f770_h retw f852_l retw f852_h retw f941_l retw f941_h retw f1209_l retw f1209_h retw f1336_l retw f1336_h retw f1477_l retw f1477_h retw f1633_l retw f1633_h ;************************************************************************** ASCII_TABLE ; Ascii value at index (0-15) ; INPUT: w - Index into the table (0-15 value) ; OUTPUT: w - Constant at that index ;************************************************************************** clc jmp PC+w retw '1' retw '2' retw '3' retw 'A' retw '4' retw '5' retw '6' retw 'B' retw '7' retw '8' retw '9' retw 'C' retw '*' retw '0' retw '#' retw 'D' ;************************************************************************** index_2_digit ; This subroutine converts a digit from 0-9 or a '*' or a '#' to a table ; lookup index which can be used by the load_frequencies subroutine. To use ; this routine, pass it a value in the 'byte' register. No invalid digits ; are used. (A, B, C, or D) ;************************************************************************** call ASCII_TABLE retp ;************************************************************************** digit_2_index ; This subroutine converts a digit from 0-9 or a '*' or a '#' to a table ; lookup index which can be used by the load_frequencies subroutine. To use ; this routine, pass it a value in the 'byte' register. No invalid digits ; are used. (A, B, C, or D) ;************************************************************************** bank serial clr temp :loop mov w,temp call ASCII_TABLE xor w,byte jz :done inc temp jb temp.4,:done jmp :loop :done mov w,temp retp ;************************************************************************** load_frequencies ; This subroutine loads the frequencies using a table lookup approach. ; The index into the table is passed in the byte register. The DTMF table ; must be in the range of $400 to $500. ;************************************************************************** mov temp,w bank sine_gen_bank mov w,>>temp and w,#%00000110 call DTMF_TABLE mov freq_count_low,w mov w,>>temp and w,#%00000110 inc wreg call DTMF_TABLE mov freq_count_high,w rl temp setb temp.3 mov w,temp and w,#%00001110 mov temp,w call DTMF_TABLE mov freq_count_low2,w mov w,temp inc wreg call DTMF_TABLE mov freq_count_high2,w retp ;************************************************************************** dial_it ; This subroutine puts out whatever frequencies were loaded ; for 1000ms, and then stops outputting the frequencies. ;************************************************************************** bank sine_gen_bank clr sine_index clr sine_index2 enable_o ; enable the output mov w,#10 call @delay_10n_ms ; delay 30ms setb dtmf_gen_en mov w,#12 call @delay_10n_ms ; delay 100ms clrb dtmf_gen_en call @disable_o ; now disable the outputs :end_dial_it retp ;************************************************************************** sine_generator1 ;(Part of interrupt service routine) ; This routine generates a synthetic sine wave with values ranging ; from -32 to 32. Frequency is specified by the counter. To set the ; frequency, put this value into the 16-bit freq_count register: ; freq_count = FREQUENCY * 6.83671552 (@50MHz) ;************************************************************************** bank sine_gen_bank clc add freq_acc_low,freq_count_low add freq_acc_high,freq_count_high sc jmp :no_change inc sine_index mov w,sine_index and w,#$1f call sine_table mov curr_sine,w ;1 ; add the velocity to sin :no_change ;************************************************************************** sine_generator2 ;(Part of interrupt service routine) ; This routine generates a synthetic sine wave with values ranging ; from -32 to 32. Frequency is specified by the counter. To set the ; frequency, put this value into the 16-bit freq_count register: ; freq_count = FREQUENCY * 6.83671552 (@50MHz) ;************************************************************************** bank sine_gen_bank clc add freq_acc_low2,freq_count_low2 add freq_acc_high2,freq_count_high2 sc jmp :no_change inc sine_index2 mov w,sine_index2 and w,#$1f call sine_table mov curr_sine2,w :no_change mov D_to_A_val,curr_sine2 ; mov sin2 into PPM0 mov sine2_temp,w ; mov the high_frequency sin wave's current value clc ; into a temporary register snb sine2_temp.7 ; divide temporary register by four by shifting right stc ; (for result = (0.25)(sin2)) rr sine2_temp clc snb sine2_temp.7 stc mov w,>>sine2_temp clc add D_to_A_val,w ; (1.25)(sin2) = sin2 + (0.25)(sin2) add D_to_A_val,curr_sine ; add the value of SIN into the PPM output add D_to_A_val,#128 ; for result = PPM0 = 1.25*sin2 + 1*sin retp ; return with page bits intact ;****************************************************************************** sine_table ; The values in this table can be changed to increase/decrease the amplitude of ; the output sine wave. ;****************************************************************************** clc jmp pc+w retw 0 retw 4 retw 8 retw 11 retw 14 retw 16 retw 18 retw 19 retw 20 retw 19 retw 18 retw 16 retw 14 retw 11 retw 8 retw 4 retw 0 retw -4 retw -8 retw -11 retw -14 retw -16 retw -18 retw -19 retw -20 retw -19 retw -18 retw -16 retw -14 retw -11 retw -8 retw -4 ;************************************************************************** ;****************************************************************************** ; Copyright © 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. ; ; Scenix Semiconductor products are not authorized for use in life support ; systems or under conditions where failure of the product would endanger ; the life or safety of the user, except when prior written approval is ; obtained from Scenix Semiconductor. ;******************************************************************************
| file: /Techref/scenix/lib/io/dev/modem/bell_103_full_dup_1_13.SRC, 45KB, , updated: 2002/12/12 09:23, local time: 2024/4/17 18:36,
3.145.12.1:LOG IN
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