start bastext 1025
start tok64 d64-yIsyoz
1 RUN00010
10 GOSUB63100:sn$="00100"
100 POKE53281,15:POKE53280,12:PRINT"{black}":PRINT"{clear}{space*11}{reverse on}{blue}micros'n'chips-4"
101 PRINT"{red}{cm a}{sh asterisk*37}{cm s}":GOSUB63100
102 PRINT"{sh -} {reverse on}{blue}{space*6}interfacing to the world{space*5}{red}{reverse off} {sh -}":ms$="ponzotutor"
103 PRINT"{red}{cm z}{sh asterisk*37}{cm x}{black}":GOSUB63200
104 ms$=" welcome! ":GOSUB63200:POKE53280,15
105 PRINT"{home}{down*10}Qnote{down}{left*4}{cm u*4}{up}:hit the @-key at any"
106 PRINT"{down}{space*6}time to return to an":PRINT"{down}{space*6}earlier section{.*3}":GOSUB50000
1000 GOSUB63100:REM micros-1
1001 sn$="01{0*3}":t$="some terminology":GOSUB63000"
1002 PRINT"{down*2}Q{reverse on}note{reverse off}: we will refer to signals as"
1003 PRINT"{down} jane{up}{left*4}{F*4}{down} or just plain 'jane'."
1004 PRINT"{down}Qa chip with a pin labelled ce{up}{left*2}FF{down} is"
1005 PRINT"{down} enabled when this pin is low{down}{left*3}{cm u*3}{up} (=0)."
1006 PRINT"{down}Qif a chip has a pin labelled something{up}{left*9}{F*9}{down}"
1007 PRINT"{down} then 'something' will happen when"
1008 PRINT"{down} this pin is low (=0)."
1009 PRINT"{down}Qa pin labelled 'enable'?":PRINT"{down} a '1' will enable!"
1010 ms$="{reverse on}{space*3}ok?{space*4}{reverse off}":GOSUB63200:GOSUB50000
1011 t$="more on the cia":GOSUB63000:PRINT"{home}{down*3}"
1015 GOSUB55000:ms$="b-half of":GOSUB63200
1020 GOSUB50000:ms$="{reverse on} cia #2{space*3}":GOSUB63200:GOSUB50000
1030 PRINT"{home}";:FORi=1TO4:PRINTbl$:NEXT
1040 PRINT"{home}";:t$="port b=parallel port=user port":GOSUB63001
1051 PRINTs$"{down*2}(this is at back of c64)":GOSUB50000
1052 PRINT"{clear}Qthis chip lives at addresses"
1053 PRINT"{down} starting at $dd00."
1054 PRINT"{down}":GOSUB56000
1057 PRINT"{down}..and 12 other registers:$dd04-$dd0f."
1058 PRINT"{down*3}Q{reverse on}poke56579,255{reverse off} and what happens:":GOSUB50000
1060 PRINT"{clear}":GOSUB56000
1063 PRINT"{down}{reverse on}{space*2}poke56579,255{space*5}"
1065 PRINT"{down}Qsince address is ${reverse on}dd{reverse off}03 then cia #2"
1070 PRINT"{down} gets a chip enable: ce{up}{left*2}RR{down}":GOSUB50000
1080 PRINT"{down}Qsince it's a {reverse on}poke{reverse off}={reverse on}write{reverse off} then r/w{up}{left}F{down}=0":GOSUB50000
1090 PRINT"{down}Qsince address is $dd{reverse on}03{reverse off} the last"
1100 PRINT"{down} 4 bits on the address bus are 0011"
1110 PRINT"{down} which selects the {reverse on}ddrb{reverse off} in the chip.":GOSUB50000
1120 PRINT"{down}Qthe data (255={1*8}) goes into {reverse on}ddrb"
1130 PRINT"{down} and port b is {reverse on}all output{reverse off}!":GOSUB50000
1140 PRINT"{clear}":GOSUB56000:PRINT"{down}Qnow we can:":PRINT"{down}{reverse on}{space*2}poke56{7*3},192{space*5}"
1150 PRINT"{down} and the data (192=";:x=192:n=7:GOSUB51001
1160 PRINTx$")":PRINT"{down} goes {reverse on}out{reverse off} port b!":GOSUB50000
1170 PRINT"{down}Qso we can turn {reverse on}on{reverse off}":PRINT"{down} 2 external devices.."
1180 FORi=1TO6:PRINT"{home}{down*10}{right*19}{reverse on}11":FORt=1TO50:NEXT
1185 PRINT"{home}{down*10}{right*19}11{reverse off}":FORt=1TO50:NEXT:NEXT:GOSUB50000
1190 PRINT"{home}{down*18}Qand turn {reverse on}off{reverse off} 6!":
1191 FORi=1TO6:PRINT"{home}{down*10}{right*21}{reverse on}{0*6}":FORt=1TO50:NEXT
1192 PRINT"{home}{down*10}{right*21}{0*6}{reverse off}":FORt=1TO50:NEXT:NEXT
1195 GOSUB50000:ms$="{space*2}slick!":GOSUB63300
1200 PRINT"{clear}Qwe may want to 'receive' outside"
1210 PRINT"{down} info thru the {reverse on}parallel port{reverse off}={reverse on}port b{reverse off}."
1220 PRINT"{down}{reverse on}{space*3}poke56577,0{space*4}{reverse off}"
1230 PRINT"{down} will make {reverse on}port b{reverse off} all input{down}{left*5}{cm u*5}{up}."
1240 PRINT"{down}Qthen we just:"
1250 PRINT"{down}{reverse on}{space*3}peek(56577){space*4}{reverse off}"
1260 PRINT"{down} to read {reverse on}prb{reverse off} which is connected"
1270 PRINT"{down} to the 'outside world'.":GOSUB50000
1280 PRINT"{clear}Qif {reverse on}parallel port{reverse off} is connected to"
1290 PRINT"{down} a printer or disk drive we don't want"
1300 PRINT"{down} the {reverse on}6510{reverse off} to spend all its time"
1310 PRINT"{down} peeking or poking this port."
1320 PRINT"{down}Qinstead we interrupt the {reverse on}6510{reverse off} only"
1330 PRINT"{down} when the 'external device' is ready"
1340 PRINT"{down} for the next data transfer."
1350 PRINT"{down}Qwe wait for the 'device' to":PRINT"{down} {reverse on}tell the cia{reverse off}!"
1360 GOSUB50000:ms$="{reverse on}{space*3}how?{space*3}":GOSUB63300
1370 PRINT"{clear}Qthere is an {reverse on}input{reverse off} pin which we can"
1380 PRINT"{down} connect to the 'external device'"
1390 PRINT"{down} called flag{up}{left*4}{F*4}{down}.":GOSUB50000
1400 PRINT"{down}Qwhen the 'device' is ready for the"
1410 PRINT"{down} next data transfer it can set flag{up}{left*4}{F*4}{down}=0"
1420 PRINT"{down} and the {reverse on}cia{reverse off} will interrupt the {reverse on}6510{reverse off}"
1430 PRINT"{down} by sending an {reverse on}i{reverse off}nterrupt {reverse on}r{reverse off}e{reverse on}q{reverse off}uest (irq{up}{left*3}{F*3}{down})"
1440 PRINT"{down}Qwhen the {reverse on}6510{reverse off} can oblige it will"
1450 PRINT"{down} read{down}{left*4}{cm u*4}{up} or write{down}{left*5}{cm u*5}{up} to the {reverse on}prb{reverse off}.":GOSUB50000
1460 PRINT"{down}Qthen the {reverse on}cia{reverse off} tells the 'device' that"
1470 PRINT"{down} it's ready for the 'next' transfer!":GOSUB50000
1480 PRINT"{down}Qit does this by setting {reverse on}pc{reverse off}=0":GOSUB50000
1490 PRINT"{clear}":ms$="{reverse on}{space*2}what?{space*3}":GOSUB63300
2000 GOSUB63100:REM micros-2
2001 sn$="02{0*3}"
2005 t$="the cia and the parallel port":GOSUB63000
2010 PRINT"{down}Qprocedure for 'recieving' data:":FORt=1TO1000:NEXT
2020 PRINT"{up}Qprocedure for 'rec{space*2}ving' data:":FORt=1TO300:NEXT
2021 PRINT"{up}Qprocedure for 'rec??ving' data:":FORt=1TO300:NEXT
2022 PRINT"{up}Qprocedure for 'receiving' data:"
2023 PRINT" {cm u*30}"
2030 PRINT"{down}1)wait for flag{up}{left*4}{F*4}{down}={reverse on}0{reverse off} from device"
2035 PRINT"{space*2}(meaning Qdata is valid).":GOSUB50000
2040 PRINT"{down}2)send interrupt to {reverse on}6510{reverse off}"
2050 PRINT"{space*2}(meaning Qdata is ready).":GOSUB50000
2060 PRINT"{down}3)when {reverse on}6510{reverse off} reads data send pc{up}{left*2}FF{down}={reverse on}0{reverse off}"
2070 PRINT"{space*2}to 'device'(Qready for next byte).":GOSUB50000
2080 PRINT"{down}{.*3}and repeat..":GOSUB50000
2090 PRINT"{clear}{down}Qprocedure for 'sending' data:"
2091 PRINT" {cm u*30}"
2100 PRINT"{down}1)put data on port b and set pc{up}{left*2}FF{down}={reverse on}0"
2105 PRINT"{space*2}Qdata is valid.":GOSUB50000
2110 PRINT"{down}2)wait for flag{up}{left*4}{F*4}{down}={reverse on}0{reverse off} from device"
2115 PRINT"{space*2}Qready for next data.":GOSUB50000
2120 PRINT"{down}3)send interrupt to {reverse on}6510{reverse off}"
2125 PRINT"{space*2}Qready for next data byte.":GOSUB50000
2130 PRINT"{down}4)when {reverse on}6510{reverse off} sends byte to port b{.*3}"
2135 PRINT"{space*2}repeat{.*3}":GOSUB50000
2140 PRINT"{clear}{down*2}Qthe little ritual of raising and"
2150 PRINT"{down} lowering the voltages on the wires"
2160 PRINT"{down} flag{up}{left*4}{F*4}{down} and pc{up}{left*2}FF{down} in order to"
2180 PRINT"{down} communicate with an external device"
2190 PRINT"{down} is called {reverse on}handshaking{reverse off}."
2200 PRINT"{down}Qif the data is sent not{down}{left*3}{cm u*3}{up} as {reverse on}bytes"
2210 PRINT"{down} (over 8 wires) but as {reverse on}bits{reverse off} (over a"
2220 PRINT"{down} single wire!) the ritual is sexier.":ms$=" sexier?":GOSUB50000
2230 GOSUB63200
3000 GOSUB63100:REM micros-3
3001 sn$="03{0*3}"
3005 t$="cereal communica":GOSUB63000
3006 t$="serial communication":GOSUB63000
3010 PRINT"{down} receiving serial bytes:"
3011 PRINT" {cm u*22}"
3020 PRINT"Qwait for {reverse on}cnt{reverse off} wire to go high {cm @}{sh @}{cm t*2}":ms$="cnt={reverse on}c{reverse off}ou{reverse on}nt{reverse off}"
3030 GOSUB63200:GOSUB50000
3040 PRINT"{home}{down*7}Qaccept bit from serial port wire ({reverse on}sp{reverse off}).":GOSUB50000
3050 PRINT"{down}Qwhen 8 such transfers take place"
3060 PRINT" interrupt the {reverse on}6510{reverse off} and give":PRINT" him the byte.":GOSUB50000
3070 PRINT"{up} her":PRINT"{down*2}..repeat..":GOSUB50000
3080 PRINT"{clear}{down*2}Qnote that we have introduced 2 {reverse on}new"
3090 PRINT"{down} pins on the 6526{down}{left*4}{cm u*4}{up} cia chip: {reverse on*2}cnt{reverse off} & {reverse on}sp{reverse off}."
3100 PRINT"{down}Qa wire from the {reverse on}cnt{reverse off} pin goes out to"
3110 PRINT"{down} the 'device' which raises and lowers"
3120 PRINT"{down} it to indicate 'data valid/invalid'."
3130 PRINT"{down}Qthe rate at which this {reverse on}cnt{reverse off} wire"
3140 PRINT"{down} oscillates between 0 and 1 gives the"
3150 PRINT"{down} baud rate.{down}{left*10}{cm u*9}"
3160 PRINT"{down}Qwhen sending serial data it's the"
3170 PRINT"{down} micro which must toggle this {reverse on}cnt{reverse off} line.":GOSUB50000
3180 PRINT"{clear}{down} sending serial bytes:"
3181 PRINT" {cm u*20}"
3190 PRINT"Qput a bit on {reverse on}sp{reverse off} pin and lower {reverse on}cnt{reverse off} P{cm @}":GOSUB50000
3200 PRINT"{down}Qdon't wait for the 'device'{.*3}just"
3210 PRINT"{down} keep putting on the bits, and toggling"
3220 PRINT"{down} the {reverse on}cnt{reverse off} line{.*3}at a specific baud rate.{down}{left*10}{cm u*9}"
3230 GOSUB50000:PRINT"{down}Qafter 8 such bit transfers send an"
3240 PRINT"{down} interrupt to {reverse on}6510{reverse off}{.*3}asking for"
3250 PRINT"{down} another byte.":PRINT"{down}Q{.*3}repeat{.*3}":ms$="baud rate?"
3260 GOSUB50000:GOSUB63300
3270 PRINT"{clear}{down*2}Qdont slow down the bit transfer"
3280 PRINT"{down} by waiting for an acknowledgement from"
3290 PRINT"{down} the receiving device (the micro"
3300 PRINT"{down} or external device). the bits get"
3310 PRINT"{down} moved at a 'specific rate'.
3320 PRINT"{down}Qit is the responsibility of the"
3330 PRINT"{down} receiver to accept the bit stream"
3335 PRINT"{down} at this rate!"
3340 PRINT"{down}Qsome 'standard' baud rates:"
3350 PRINT"{down}110,150,300,600,1200,2400,4800,9600.":GOSUB50000
4000 GOSUB63100:REM micros-4
4001 sn$="04{0*3}"
4005 t$="cia pinout":GOSUB63000
4010 GOSUB54000
4040 y=9:x=2:m$="{reverse on}ce":GOSUB54300
4041 PRINTp$"Qchip enable":PRINTp$"{down*2} (when address":PRINTp$"{down*4} is right)."
4042 GOSUB50000:GOSUB54310
4050 y=10:x=2:m$="{reverse on}r/w":GOSUB54300
4051 PRINTp$"Qread/write ":PRINTp$"{down*2}{space*2}read=1{space*6}":PRINTp$"{down*4}{space*2}write=0{space*2}"
4052 GOSUB50000:GOSUB54310
4060 y=11:x=2:m$="{reverse on}clock":GOSUB54300
4061 PRINTp$"Qphase 2{space*4}":PRINTp$"{down*2} clock{space*8}":PRINTp$"{down*4}{space*11}"
4062 GOSUB50000:GOSUB54310
4070 y=13:x=2:m$="{reverse on}irq":GOSUB54300
4071 PRINTp$"Qinterrupt{space*2}":PRINTp$"{down*2} the {reverse on}6510{reverse off}.{space*4}":PRINTp$"{down*4}{space*11}"
4072 GOSUB50000:GOSUB54310
4080 y=15:x=2:m$="{reverse on}a3":GOSUB54300
4081 y=16:x=2:m$="{reverse on}a2":GOSUB54300
4082 y=17:x=2:m$="{reverse on}a1":GOSUB54300
4083 y=18:x=2:m$="{reverse on}a0":GOSUB54300
4084 PRINTp$"Q4 pins to{space*2}":PRINTp$"{down*2} select a {reverse on}6526":PRINTp$"{down*4} register. "
4085 GOSUB50000:GOSUB54310
4086 y=15:x=2:m$="{reverse on}a3":GOSUB54310
4087 y=16:x=2:m$="{reverse on}a2":GOSUB54310
4088 y=17:x=2:m$="{reverse on}a1":GOSUB54310
4089 y=18:x=2:m$="{reverse on}a0":GOSUB54310
4090 y=22:x=1:m$="{reverse on}reset":GOSUB54300
4091 PRINTp$"Qset all{space*4}":PRINTp$"{down*2} registers to":PRINTp$"{down*4} zero.{space*5}"
4092 GOSUB50000:GOSUB54310
4100 y=5:x=8:m$="{reverse on}+5 volts":GOSUB54300
4101 PRINTp$"Qthe innards":PRINTp$"{down*2} need power!!":PRINTp$"{down*4}{space*11}"
4102 GOSUB50000:GOSUB54310
4110 y=21:x=7:m$="{reverse on}ground":GOSUB54300
4111 PRINTp$"Q{.*3}and{space*5}":PRINTp$"{down*2} ground!{space*5}":PRINTp$"{down*4}{space*11}"
4112 GOSUB50000:GOSUB54310
4120 y=12:x=13:m$="{reverse on}flag":GOSUB54300
4121 PRINTp$"Qfrom an{space*4}":PRINTp$"{down*2} external{space*4}":PRINTp$"{down*4} device{space*4}"
4122 GOSUB50000:GOSUB54310
4130 y=13:x=13:m$="{reverse on}sp":GOSUB54300
4131 PRINTp$"Qthe serial ":PRINTp$"{down*2} port.{space*7}":PRINTp$"{down*4}{space*11}"
4132 GOSUB50000:GOSUB54310
4140 y=14:x=13:m$="{reverse on}cnt":GOSUB54300
4141 PRINTp$"Qto time the":PRINTp$"{down*2} serial bit{space*2}":PRINTp$"{down*4} transfer. "
4142 GOSUB50000:GOSUB54310
4150 y=15:x=13:m$="{reverse on}pc":GOSUB54300
4151 PRINTp$"Qperipheral ":PRINTp$"{down*2} control{.*3}to":PRINTp$"{down*4} handshake."
4152 GOSUB50000:GOSUB54310
4160 y=4:x=1:m$="{reverse on}{left}data{down}{left*3}bus":GOSUB54300
4161 y=9:x=13:m$="{reverse on}port a":GOSUB54300
4162 y=17:x=13:m$="{reverse on}port b":GOSUB54300
4163 PRINTp$"Qand the{space*4}":PRINTp$"{down*2} data bus and":PRINTp$"{down*4} ports{.*3}{space*2}"
4164 GOSUB50000
4165 PRINTp$"Qwe said it ":PRINTp$"{down*2} was a 40-pin":PRINTp$"{down*4} chip.{space*5}"
4166 GOSUB50000
4167 PRINTp$"Q39 pins are":PRINTp$"{down*2} accounted{space*3}":PRINTp$"{down*4} for{.*3}{space*4}"
4168 GOSUB50000
4169 PRINTp$"Qwhere's{space*4}":PRINTp$"{down*2} the 40th pin":PRINTp$"{down*4} {?*6}{space*4}"
4170 GOSUB50000:PRINTLEFT$(d$,19)LEFT$(r$,9)"{cm r}{down}{left}{cm z}{sh asterisk*3}";
4180 FORi=1TO10:PRINT"{reverse on}tod{left*3}";:FORt=1TO50:NEXT:PRINT"{reverse off}tod{left*3}";:FORt=1TO50
4190 NEXT:NEXT:ms$="{space*3}time":GOSUB63300:ms$="{space*2}of day":GOSUB63300
4200 PRINT"{clear}{down*2}Qif a 60 hertz signal":PRINT"{space*6}{cm u*8}"
4210 PRINT" is fed to the {reverse on}cia{reverse off} via the"
4230 PRINT"{down} {reverse on}t{reverse off}ime {reverse on}o{reverse off}f {reverse on}d{reverse off}ay (tod) pin{.*3}"
4240 PRINT"{down} and we ask nicely{.*3} then the {reverse on}6526":PRINT"{down} will keep track of:"
4250 PRINT"{down}{reverse on} hours,minutes,seconds and":PRINT"{reverse on} tenths of seconds!{space*7}"
4260 ms$="tick!tick!":GOSUB63200:GOSUB50000
4270 PRINT"{clear}{down*2}Qwe said the {reverse on}6526{reverse off} has 16 internal"
4280 PRINT"{down} registers{.*3}and we've mentioned only"
4290 PRINT"{down} four:"
4300 PRINT"{down}{reverse on}0{reverse off}:peripheral register a"
4301 PRINT"{reverse on}1{reverse off}:peripheral register b"
4302 PRINT"{reverse on}2{reverse off}:data direction register a"
4303 PRINT"{reverse on}3{reverse off}:data direction register b"
4304 PRINT"{down*2}{.*3}and the 12 others??":ms$="{space*2}{reverse on}4{reverse off} to {reverse on}f{reverse off}":GOSUB63200:GOSUB50000
5000 GOSUB63100:REM micros-5
5001 sn$="05{0*3}"
5005 t$="cia registers":GOSUB63000
5010 PRINT"{down*2}Qwe need a register or two to do"
5020 PRINT"{down} the {reverse on}cnt{reverse off} (baud rate) timing for the"
5030 PRINT"{down} serial port {reverse on}sp{reverse off}."
5040 PRINT"{down}Qhow about two 8-bit registers which"
5050 PRINT"{down} we can load with a 2-byte number from"
5060 PRINT"{down} 0 to 65535 (decimal).":PRINT"{down}Qthen we can have these"
5070 PRINT"{down} two registers count down to zero"
5080 PRINT"{down} ..counting down at the rate of the"
5090 PRINT"{down} phase 2 clock (1 megahertz).":GOSUB50000
5100 PRINT"{clear}{down}Qthis will give us a maximum time of"
5110 PRINT"{down} 65535 microseconds=65.5 milliseconds"
5120 PRINT"{down} which (by micro standards) is plenty!":GOSUB50000
5130 PRINT"{down}Qif we want larger time intervals we"
5140 PRINT"{down} can have two 2-byte timer registers."
5150 PRINT"{down}Qwhen the first counts down to zero"
5160 PRINT"{down} we start the second timer."
5170 PRINT"{down}Qwe may also want to have one of these"
5180 PRINT"{down} 2-byte timers count 'external' pulses"
5190 PRINT"{down} which come in on the {reverse on}cnt{reverse off} pin.":GOSUB50000
5200 PRINT"{down}Qcnt={reverse on}count{reverse off}..remember?":GOSUB50000
5210 PRINT"{clear}{down*2}Qthen, of course, we want 4 more"
5220 PRINT"{down} registers devoted to the {reverse on}time of day{reverse off}:"
5230 PRINT"{down}one register to hold hours.."
5231 PRINT"{down}one register to hold minutes.."
5232 PRINT"{down}one register to hold seconds.."
5233 PRINT"{down}one register to hold 10ths of seconds.":GOSUB50000
5235 ms$=" 4 to go!":GOSUB63300
5240 PRINT"{clear}{down}Qof course our hours{down}{left*5}{cm u*5}{up} register"
5250 PRINT"{down} need only hold hours from 0 to 23"
5255 PRINT"{down} and minute & seconds from 0 to 59.."
5256 PRINT"{space*5}{cm u*6}{space*3}{cm u*7}"
5260 PRINT" how about a 24 hour clock:":PRINT"{down} from"
5270 PRINT"{down} {reverse on}0{reverse off}hours {reverse on}0{reverse off}minutes {reverse on}0{reverse off}seconds {reverse on}0{reverse off}10ths"
5280 PRINT"{down} to:"
5290 PRINT"{down} {reverse on}23{reverse off}hours {reverse on}59{reverse off}minutes {reverse on}59{reverse off}seconds {reverse on}9{reverse off}10ths":GOSUB50000
5300 PRINT"{clear}{down*2}Qin fact it may be convenient for"
5310 PRINT"{down} the user of this clever chip if we"
5320 PRINT"{down} have the numbers (hours,minutes,etc.)"
5330 PRINT"{down} stored in the registers in the format:"
5340 PRINT"{down} {reverse on}first{reverse off} digit:{reverse on}second{reverse off} digit":GOSUB50000
5350 PRINT"{down}example: 23 would be stored as:":PRINT"{cm u*7}"
5360 PRINT" 0010 0011"
5361 PRINT"{space*3}^{space*4}^^"
5362 PRINT"{space*3}2{space*5}3":GOSUB50000
5370 PRINT"{clear}{down*8}Qthis slick format has a name{.*4}":GOSUB50000
5375 t$="binary coded decimal=bcd":GOSUB63000
5380 PRINT"{down*3}Q59=0101 1001":PRINT"{down}Q98=1001 1{0*3}":PRINT"{down}Q 2={0*4} 0010"
5390 PRINT"{down}Q11={0*3}1 {0*3}1":PRINT"{down}Q22=0010 0010":PRINT"{down}Q19={0*3}1 1001"
5400 GOSUB50000:ms$="very nice!":GOSUB63300
5410 PRINT"{clear}{down*2}Qof course we only need hours":PRINT"{down} from 0 to 23:"
5420 PRINT"{down} or {reverse on}{0*4}{reverse off} {reverse on}{0*4}{reverse off} to {reverse on}0010{reverse off} {reverse on}0011":GOSUB50000
5430 PRINT"{down*2}Qyou don't like 24 hour clocks?"
5440 PRINT"{down} how about hours from 0 to 12 with"
5450 PRINT"{down} {reverse on}am{reverse off} and {reverse on}pm{reverse off} indicators?":GOSUB50000
5460 PRINT"{down} {reverse on}0{reverse off}{0*3} {0*4} to {reverse on}0{reverse off}001 0010{reverse off} = {reverse on}am"
5470 PRINT"{down} {reverse on}1{reverse off}{0*3} {0*4} to {reverse on}1{reverse off}001 0010{reverse off} = {reverse on}pm"
5480 ms$="msb=am/pm":GOSUB63200:GOSUB50000
5490 PRINT"{clear}{down}Qwe also want to tell the {reverse on}6526{reverse off} chip"
5500 PRINT"{down} when{down}{left*4}{cm u*4}{up} to interrupt the {reverse on}6510{reverse off} via"
5510 PRINT"{down} the irq{up}{left*3}{F*3}{down} pin.":GOSUB50000    :
5520 PRINT"{down} ..when the timers count down to zero":GOSUB50000
5530 PRINT"{down} ..or a flag{up}{left*4}{F*4}{down} goes low..":GOSUB50000
5540 PRINT"{down} ..or the {reverse on}serial port{reverse off} has"
5550 PRINT"{down}{space*3}collected 8 bits=1 byte.":GOSUB50000
5560 PRINT"{down}Qall this info needs to be given to"
5570 PRINT"{down} the {reverse on}6526{reverse off}{.*3}by writing to the"
5580 PRINT"{down} {reverse on}i{reverse off}nterrupt {reverse on}c{reverse off}ontrol {reverse on}r{reverse off}egister (icr).":GOSUB50000
5590 PRINT"{clear}{down*2}Qif we are to collect 8 bits"
5600 PRINT"{down} (=1 byte) until the {reverse on}6510{reverse off} can read"
5610 PRINT"{down} it, then where should we store it?":GOSUB50000
5620 PRINT"{down}Qin yet another register, of course!"
5630 PRINT"{down} the {reverse on}serial data register{reverse off}.":GOSUB50000:ms$="finished?":GOSUB63300
5640 PRINT"{clear}{down}Qfinally (2 more registers to go!)"
5650 PRINT"{down} we need to tell the {reverse on}6526{reverse off} how we"
5660 PRINT"{down} want the two 2-byte timers to work.":GOSUB50000
5670 PRINT"{down}Qthings like:"
5680 PRINT"{down}Qwhen to start/stop them.":GOSUB50000
5681 PRINT"{down}Qsend timer output to a port pin.":GOSUB50000
5682 PRINT"{down}Qlet timer b count {reverse on}cnt{reverse off} pulses.":GOSUB50000
5683 PRINT"{down}Q..or maybe count {reverse on}phase 2 clock pulses.":GOSUB50000
5684 PRINT"{down}Q..or maybe count the times that"
5685 PRINT"{down}{space*3}timer a 'zeros out'..":GOSUB50000
5690 PRINT"{clear}{down*4}Qso{.*3}we have two more registers which"
5700 PRINT"{down} control these two timer operations:"
5710 PRINT"{down*3} {reverse on}control register a"
5711 PRINT"{down} {reverse on}control register b"
5720 ms$="{reverse on}altogether{reverse off}":GOSUB50000:GOSUB63300
6000 GOSUB63100:REM micros-6
6001 sn$="06{0*3}"
6005 t$="cia registers":GOSUB63000
6010 GOSUB54400:FORi=0TO15:PRINTr$(i):GOSUB50000:NEXT
6020 ms$="whattachip":GOSUB63300
7000 GOSUB63100:REM micros-7
7001 sn$="07{0*3}"
7005 t$="the tape drive":GOSUB63000
7010 PRINT"{down*2}Qthis is a serial port too,"
7020 PRINT"{down} with each byte going to the tape unit"
7030 PRINT"{down} as 8 bits{.*3}one after the other."
7040 PRINT"{down}Qthe tape drive needs four control"
7050 PRINT"{down} signals:":GOSUB50000
7060 PRINT"{down}Qa signal to turn on/off the motor.":GOSUB50000
7070 PRINT"{down}Qa serial write{down}{left*5}{cm u*5}{up} line":GOSUB50000
7080 PRINT"{down}Qa line to read{down}{left*4}{cm u*4}{up}":GOSUB50000
7090 PRINT"{down}Qa line to sense if any button"
7100 PRINT"{down} has been pushed down!":GOSUB50000:GOSUB63000:PRINT"{down*2}"
7105 PRINTSPC(18)"{reverse on}p{down}{left}o{down}{left}r{down}{left}t"
7110 PRINT"{home}{down*4}{reverse on}cassette motor{reverse off}{sh asterisk*3}{cm w}":GOSUB50000
7111 PRINT"{reverse on}cassette sense{reverse off}{sh asterisk*3}{cm w}":GOSUB50000
7112 PRINT"{reverse on}cassette write{reverse off}{sh asterisk*3}{cm w}":GOSUB50000
7113 PRINT"{reverse on}cassette read {reverse off}{sh asterisk*3}{cm w}":GOSUB50000
7114 PRINT"{reverse on}..and +5 volts{reverse off}{sh asterisk*3}{cm w}":GOSUB50000
7115 PRINT"{reverse on}{.*3}ground{space*5}{reverse off}{sh asterisk*3}{cm w}":GOSUB50000
7120 PRINT"{down*3}Qand where do the{sh space}top 4 signals"
7130 PRINT"{down} go to{.*3}in the c64?":GOSUB50000
7140 PRINT"{down}{.*3}to the {reverse on}6510{reverse off}!!":GOSUB50000
7150 PRINT"{clear}{down*5}well{.*3}sort of{.*3}":FORt=1TO1000:NEXT
7160 PRINT"{clear}{down*2}the {reverse on}6510{reverse off} has (believe it or not)"
7170 PRINT"{down} an input/output port built right in!"
7175 PRINT"{down} (6 bits worth)":GOSUB50000
7180 PRINT"{down} and even a {reverse on}data direction register{reverse off}!"
7190 PRINT"{down}Qmotor control,sense and write lines"
7200 PRINT"{down} go to 3 pins of the {reverse on}6510{reverse off} i/o port."
7210 PRINT"{down}Qthe read{down}{left*4}{cm u*4}{up} line (an 'input'"
7220 PRINT"{down} from the tape drive) goes to a..":GOSUB50000:ms$="{space*2}ready?"
7230 PRINT"{home}{down*18} flag{up}{left*4}{F*4}{down} input of {reverse on}cia #1{reverse off}!":GOSUB50000
7235 t$="6510 i/o port":GOSUB63000:PRINT"{down}"
7236 PRINT"{sh asterisk*4}{cm s}"
7240 PRINT"{reverse on}6{reverse off}{space*2}5{cm q}{sh asterisk*2}"
7241 PRINT"{reverse on}5{reverse off}{space*2}4{cm q}{sh asterisk*2}"
7242 PRINT"{reverse on}1{reverse off}{space*2}3{cm q}{sh asterisk*2}"
7243 PRINT"{reverse on}0{reverse off}{space*2}2{cm q}{sh asterisk*2}"
7244 PRINT"{space*3}1{cm q}{sh asterisk*2}"
7245 PRINT"{space*3}0{cm q}{sh asterisk*2}"
7250 y=8:x=7:m$="{reverse on}cass. write":GOSUB54300:GOSUB50000:GOSUB54310
7260 y=7:x=6:m$="{reverse on}{arrow left}cass. sense":GOSUB54300:GOSUB50000:GOSUB54310
7270 y=6:x=7:m$="{reverse on}cass. motor":GOSUB54300:GOSUB50000:GOSUB54310
7280 PRINTp$"Qand the first":PRINTp$"{down}three pins":PRINTp$"{down*2}of this 6510 port?"
7285 GOSUB50000:m$="":GOSUB54310
7290 y=11:x=7:m$="{reverse on}loram":GOSUB54300:PRINTp$"Qenable/disable"
7300 PRINTp$"{down}the rom at":PRINTp$"{down*2}$8{0*3}-$9{f*3}!"
7305 ms$="remember?":GOSUB63200:GOSUB50000:GOSUB54310
7310 y=10:x=7:m$="{reverse on}hiram":GOSUB54300:PRINTp$"Qenable/disable"
7320 PRINTp$"{down}the rom at":PRINTp$"{down*2}$a{0*3} & $e{0*3}!"
7325 GOSUB63200:GOSUB50000:GOSUB54310
7330 y=9:x=7:m$="{reverse on}charen":GOSUB54300:PRINTp$"Qenable/disable"
7340 PRINTp$"{down}the character":PRINTp$"{down*2}rom!!":GOSUB63200:GOSUB50000
7360 PRINT"{home}{down*12}..and the data direction?":GOSUB50000:GOSUB55300
7365 PRINT"{home}{down*5}{right}"LEFT$(rg$,30)"{cm t*2}"
7370 PRINT"{home}{down*14}10{1*4}=out in out out out out":GOSUB50000
7375 t$="the 6510 i/o port":GOSUB63000
7380 PRINT"{down*2}Qand where is this i/o port 'inside'"
7390 PRINT"{down} the {reverse on}6510{reverse off}?":PRINT"{down}Qto read/write to this port we"
7400 PRINT"{down}{reverse on} poke 1 {reverse off} or {reverse on} peek 1 "
7410 PRINT"{down} (it 'responds' to location one).":GOSUB50000
7420 PRINT"{down}Qand the data direction register?":GOSUB50000
7430 PRINT"{down}{reverse on} poke 0{reverse off} or {reverse on}peek 0{reverse off}":PRINT"{down}(it 'responds' to location zero!)"
7440 PRINT"{down}10{1*4}=out in out out out out":PRINT"{down}Qso peek(0)=47"
7450 GOSUB50000:PRINT"{clear}{down*6}Qthis {reverse on}6510{reverse off} is some chip!":ms$="some chap"
7460 GOSUB50000:GOSUB63200
7470 PRINT"{clear}{down*6}Qbut that's{down}{left*6}{cm u*6}{up} another story!"
49000 ms$="au revoir!{home}":GOSUB63200:sn$="{0*3}10":GOSUB63520:END
50000 GETa$:IFa$<>""THEN50000
50001 GETa$:IFa$=""THEN50001
50002 IFa$="@"THEN63500
50003 RETURN
51000 n=3
51001 x$="":FORu=nTO0STEP-1:x%=x/(2^u):x=x-x%*(2^u):x$=x$+CHR$(48+x%)
51002 NEXT:RETURN
51120 PRINT"{down} which (by micro standards) is plenty"
52000 m=3
52001 y$="":FORv=mTO0STEP-1:y%=y/(16^v):y=y-y%*(16^v)
52002 y$=y$+CHR$(48+y%-7*(y%>9)):NEXT:RETURN
54000 PRINT"{home}{down*3}";
54010 PRINT"dataQ{sh asterisk*2}
54020 PRINT"{sh asterisk}bus{sh -} {cm a}{sh asterisk}+5 volts
54030 PRINT"{sh asterisk*2}Q.{sh -} {sh -}
54040 PRINT" {cm a}{cm e*3}{sh asterisk}{cm e}{sh asterisk*3}{cm s}
54050 PRINT" {sh -}FF{space*6}{cm q}{sh asterisk*2}"
54060 PRINT"{sh asterisk}{cm w}ceR{space*5}{cm q}..port a"
54070 PRINT"{sh asterisk}{cm w}r/w{space*5}{cm q}{sh asterisk*2}"
54080 PRINT"{sh asterisk}{cm w}clock{space*3}{sh -}{space*2}{F*4}"
54090 PRINT" {sh -}{F*3}{space*5}{cm q}{arrow left}{sh asterisk}flag"
54100 PRINT"{arrow left}{cm w}irq{space*5}{cm q}{sh asterisk*2}sp "
54110 PRINT" {sh -}{space*8}{cm q}{sh asterisk*2}cnt"
54120 PRINT"{sh asterisk}{cm w}a3{space*6}{cm q}{sh asterisk*2}pc"
54130 PRINT"{sh asterisk}{cm w}a2{space*6}{cm q}{sh asterisk*2}"
54140 PRINT"{sh asterisk}{cm w}a1{space*6}{cm q}..port b"
54150 PRINT"{sh asterisk}{cm w}a0{space*6}{cm q}{sh asterisk*2}
54160 PRINT" {cm z}{cm r}{sh asterisk*4}{cm r}{sh asterisk*2}{cm x}
54170 PRINT"{space*2}^{space*4}{sh -}
54180 PRINT" {F*5} ground"
54190 PRINT" reset
54200 RETURN
54300 PRINTLEFT$(d$,y)RIGHT$(r$,x)m$:RETURN
54310 PRINTp$;:FORi=1TO5:PRINTbl$;:NEXT
54320 m$=MID$(m$,2):GOSUB54300:RETURN
54400 DIM r$(15):r$(0)="{down}{reverse on}0{reverse off}:peripheral register a"
54401 r$(1)="{reverse on}1{reverse off}:peripheral register b"
54402 r$(2)="{reverse on}2{reverse off}:data direction register a"
54403 r$(3)="{reverse on}3{reverse off}:data direction register b"
54404 r$(4)="{reverse on}4{reverse off}:timer a:lo byte"
54405 r$(5)="{reverse on}5{reverse off}:timer a:hi byte"
54406 r$(6)="{reverse on}6{reverse off}:timer b:lo byte"
54407 r$(7)="{reverse on}7{reverse off}:timer b:hi byte"
54408 r$(8)="{reverse on}8{reverse off}:10ths of seconds"
54409 r$(9)="{reverse on}9{reverse off}:seconds"
54410 r$(10)="{reverse on}a{reverse off}:minutes"
54411 r$(11)="{reverse on}b{reverse off}:hours & am/pm"
54412 r$(12)="{reverse on}c{reverse off}:serial data register"
54413 r$(13)="{reverse on}d{reverse off}:interrupt control register"
54414 r$(14)="{reverse on}e{reverse off}:control register a"
54415 r$(15)="{reverse on}f{reverse off}:control register b"
54416 RETURN
55000 PRINT"{sh asterisk*9}Q{sh asterisk}
55010 PRINT"{sh asterisk*8}Q{sh +}{sh asterisk}
55020 PRINT"{sh asterisk}data{sh asterisk*2}Q{sh +*2}{sh asterisk}
55030 PRINT"{sh asterisk}bus {sh asterisk}Q{sh +*3}{sh asterisk}
55040 PRINT"{sh asterisk*5}Q{sh +*4}{sh asterisk}
55050 PRINT"{sh asterisk*4}Q{sh +*5}{sh asterisk}
55060 PRINT"{sh asterisk*3}Q{sh +*6}{sh asterisk}
55070 PRINT"{sh asterisk*2}Q{sh +*7}{sh asterisk}
55080 PRINT" {cm a}{cm e*8}{sh asterisk*5}{cm s}
55090 PRINT" {sh -}FF{space*11}{cm q}{sh asterisk*2}
55100 PRINT"{sh asterisk}{cm w}ce{space*11}{cm q}{sh asterisk*2} {reverse on}p"
55101 PRINT" {sh -}{space*2}F{space*10}{cm q}{sh asterisk*2} {reverse on}o"
55102 PRINT"{sh asterisk}{cm w}r/w{space*10}{cm q}{sh asterisk*2} {reverse on}r"
55103 PRINT" {sh -}{space*13}{cm q}{sh asterisk*2} {reverse on}t"
55104 PRINT" {sh -}{space*13}{cm q}{sh asterisk*2}"
55110 PRINT" {sh -}{space*13}{cm q}{sh asterisk*2} {reverse on}b"
55120 PRINT"{sh asterisk}{cm w}a3{space*11}{cm q}{sh asterisk*2}"
55150 PRINT"{sh asterisk}{cm w}a2{space*11}{sh -}"
55160 PRINT"{sh asterisk}{cm w}a1{space*11}{sh -}"
55170 PRINT"{sh asterisk}{cm w}a0{space*11}{sh -}{home}"
55200 bl$="":FORi=1TO39:bl$=bl$+" ":NEXT:GOSUB55300
55210 d$="{home}{down*13}":c$="{right*13}":PRINTd$c$rg$"{reverse on}prb"
55220 PRINTd$LEFT$(c$,9)rg$"{left}{reverse on}ddrb":s$="{home}{down*4}{right*15}":RETURN
55300 b$="OP{down}{left*2}":rg$="":FORi=1TO8:rg$=rg$+b$:NEXT:rg$=rg$+"{cm t*2}{down}{left*3}":RETURN
56000 PRINT" $dd00(56576)={reverse on}port a{reverse off}"
56001 PRINT" $dd01(56577)={reverse on}port b{reverse off}"
56002 PRINT" $dd02(56578)={reverse on}ddra{space*2}"
56003 PRINT" $dd03(56579)={reverse on}ddrb{space*2}"
56004 RETURN
63000 PRINT"{clear}";
63001 l=LEN(t$):uu$="":FORi=1TOl:uu$=uu$+" ":NEXT:tt$=uu$+t$
63002 PRINT" {cm a}";:FORi=1TOl:PRINT"{sh asterisk}";:NEXT:PRINT"{cm s}"
63003 PRINT" {sh -}";:FORi=1TOl:PRINT" ";:NEXT:PRINT"{reverse off}{sh -}"
63004 PRINT" {cm z}";:FORi=1TOl:PRINT"{sh asterisk}";:NEXT:PRINT"{cm x}":PRINT"{up*2}{right*2}{reverse on}{red}";
63005 FORi=1TOl:PRINTMID$(tt$,i+1,l):PRINT"{up}{right*2}{reverse on}";:FORt=1TO50:NEXT
63006 NEXT:PRINT"{black}":RETURN
63100 bt$="{home}{down*24}"
63101 pt$="{red}{cm a}{sh asterisk*10}{cm s}{down}{left*12}{sh -}{right*10}{sh -}{down}{left*12}{cm z}{cm r}{sh asterisk*8}{cm r}{cm x}"
63102 pt$=pt$+"{down}{left*13}N{cm t*12}M{down}{left*14}{cm g}{=*12}{cm m}"
63103 pt$=pt$+"{down}{left*14}PO{cm t*10}PO{up*4}{left*12}"
63104 pt$=bt$+"{up*6}{right*26}"+pt$+"{black}"
63105 sn=1030:IFPEEK(0)=47THENsn=2054
63110 d$="{home}":FORi=1TO25:d$=d$+"{down}":NEXT
63120 r$="":FORi=1TO40:r$=r$+"{right}":NEXT:p$="{home}{down*3}{right*20}"
63130 bl$="{space*18}{down}{left*18}"
63199 RETURN
63200 FORi=1TO2:PRINTpt$"{space*10}"
63201 FORt=1TO50:NEXT
63202 PRINTpt$ms$
63203 FORt=1TO50:NEXT:NEXT:RETURN
63300 GOSUB63200:FORt=1TO1000:NEXT:RETURN
63500 vs=VAL(sn$):vs=vs-1000:IFvs<1000THENvs=100
63510 sn$=MID$(STR$(vs),2):sn$=RIGHT$("{0*5}"+sn$,5):GOSUB63520:RUN
63520 FORi=1TO5:POKEsn+i-1,ASC(MID$(sn$,i,1)):NEXT:RETURN
stop tok64
(bastext 1.0)