1 00:00:00,710 --> 00:00:01,140 Hello. 2 00:00:01,200 --> 00:00:01,710 Welcome back. 3 00:00:01,920 --> 00:00:07,190 So let's develop our you outcry over creates a bit of space over here. 4 00:00:07,230 --> 00:00:11,910 I'm going to start off with our directives area 5 00:00:17,710 --> 00:00:18,860 to you. 6 00:00:20,280 --> 00:00:24,600 And then there's the code area is read only 7 00:00:28,180 --> 00:00:28,870 we aligned 8 00:00:31,680 --> 00:00:33,000 that thumb. 9 00:00:33,580 --> 00:00:34,350 This the entry 10 00:00:38,320 --> 00:00:45,720 we're going to export our main label right. 11 00:00:46,350 --> 00:00:46,770 And 12 00:00:49,670 --> 00:00:59,250 we going to start off over here on a score on a scope made and we're going to branch to fess up routine 13 00:00:59,430 --> 00:01:01,120 as you tune it. 14 00:01:01,500 --> 00:01:02,120 Right. 15 00:01:02,130 --> 00:01:06,060 So we start off by implementing our you turn it 16 00:01:10,630 --> 00:01:13,060 you turn it like this. 17 00:01:14,260 --> 00:01:14,710 OK. 18 00:01:14,800 --> 00:01:17,830 This was rather far away. 19 00:01:18,220 --> 00:01:20,410 We just move this a bit 20 00:01:26,980 --> 00:01:27,970 right. 21 00:01:28,260 --> 00:01:29,530 Okay. 22 00:01:30,070 --> 00:01:32,940 So we going to initialize that you add. 23 00:01:33,180 --> 00:01:35,640 I'm gonna start off by pushing the link register 24 00:01:39,080 --> 00:01:41,930 save the current value of the link register as it is 25 00:01:48,710 --> 00:01:51,390 and then next I'm going to load a. 26 00:01:53,900 --> 00:01:56,180 What you got RCC. 27 00:01:56,210 --> 00:02:00,500 Register and then enable clock access to that you do load 28 00:02:04,360 --> 00:02:05,000 are won 29 00:02:07,580 --> 00:02:10,430 because this control 30 00:02:13,530 --> 00:02:22,970 are a seat to see you at the school are just the name of the register and then or take what is in this 31 00:02:22,970 --> 00:02:25,520 register and put it in our receiver like this 32 00:02:30,160 --> 00:02:32,500 and then perform an operation 33 00:02:37,420 --> 00:02:39,520 with no symbolic name. 34 00:02:39,520 --> 00:02:46,090 You are to enable or is it you are to enable 35 00:02:50,240 --> 00:02:53,870 the once that is done or right the resort report to the register. 36 00:02:58,490 --> 00:02:59,290 Right. 37 00:02:59,340 --> 00:03:09,680 Once we've done this okay once we've done this we can um we can enable the clock access to GPL you put 38 00:03:09,770 --> 00:03:10,070 a 39 00:03:19,990 --> 00:03:21,730 For those of you who are not familiar. 40 00:03:21,970 --> 00:03:23,890 Yeah I'm wondering about this. 41 00:03:23,930 --> 00:03:26,630 I just put a C code here in C language. 42 00:03:26,740 --> 00:03:37,690 This is going to be I think this control using synapses is gonna be a source control you at just control 43 00:03:37,710 --> 00:03:48,350 R C G C you UT and then all you add 0 enable this is what we type in C language to get this in bare 44 00:03:48,350 --> 00:03:50,950 metal and add it to C right. 45 00:03:50,950 --> 00:04:00,090 So the next thing we're going to do is it's going to enable clock access for our GPA you put a. 46 00:04:00,380 --> 00:04:07,650 So I'm gonna in C language is gonna be cis control our C G C GP I O A No. 47 00:04:07,700 --> 00:04:16,080 C G C GPA oh and then it becomes GPA a e n over here would perform an operation for that so I'm gonna 48 00:04:16,090 --> 00:04:28,840 do a load and assembly we do load this control our CTC GPA you go ah we take what is in there and put 49 00:04:28,840 --> 00:04:30,460 it into register our 0 50 00:04:34,610 --> 00:04:46,490 and we perform an operation with with our GPA you a enable and we start a registered back we store the 51 00:04:46,490 --> 00:04:50,780 um the resorts back into the register like this. 52 00:04:50,780 --> 00:04:51,690 Okay. 53 00:04:51,710 --> 00:05:00,040 So this will enable clock access which EPR puts a the next then we Queen to do is we Queen to set a 54 00:05:00,070 --> 00:05:08,950 set or you pays for alternate function but before we do that we can digitally enable are where you are 55 00:05:08,960 --> 00:05:15,920 to PS P is you're in Pier 1 and we're going to digitally enabled them to come over here and 56 00:05:19,390 --> 00:05:31,130 I'm gonna do it see language 0 2 GPL you a digital enable register and I'm simply going to 57 00:05:34,070 --> 00:05:43,720 0 to sort of write this This will correspond to the bit that uh this corresponds to the bid for GPL 58 00:05:43,720 --> 00:05:55,000 you pin a and uh GPL you open one in GPL you pin zero right to so do this um in an assembly load are 59 00:05:55,120 --> 00:06:07,630 one we have copy I do a d n on this call R and then we take the content put it into our 0 like this 60 00:06:08,740 --> 00:06:20,470 we perform an operation of our 0 and 0 x 0 3 0 3. 61 00:06:20,800 --> 00:06:33,510 Remember this is the same as this or this or this is 0 before the digits doesn't matter right. 62 00:06:33,610 --> 00:06:44,440 So after we do this we write the results back store our as you are 1 like this okay. 63 00:06:44,590 --> 00:06:48,700 So once that is done we can figure that you are we go to the port control register 64 00:06:51,820 --> 00:06:58,900 and then we first cleared a port control field for P E 1 and P issue and then we write new values to 65 00:06:58,900 --> 00:07:00,280 that field. 66 00:07:00,280 --> 00:07:00,840 Okay. 67 00:07:00,910 --> 00:07:01,830 So I'm going to 68 00:07:04,980 --> 00:07:07,660 this let's see. 69 00:07:08,310 --> 00:07:09,400 And see language. 70 00:07:09,540 --> 00:07:13,620 We do it GPL U A P C T RL. 71 00:07:13,710 --> 00:07:21,440 This the port control register P.S. Well it is and then what we're going to do to clear a bit. 72 00:07:21,450 --> 00:07:22,410 We do. 73 00:07:23,310 --> 00:07:26,300 Um no sound because. 74 00:07:26,350 --> 00:07:34,080 And then to Tuesday over here and then we're going to use this hexadecimal number to clear the bit for 75 00:07:36,750 --> 00:07:45,590 for what you call it for P is you and Pier 1 right. 76 00:07:50,880 --> 00:08:01,490 Okay so I'm going to going to implement this and once we've cleared a bit we would need to sort of we'll 77 00:08:01,500 --> 00:08:06,860 need to we need to write new bits to it. 78 00:08:07,300 --> 00:08:13,830 We need to configure the P issue to p a one as you at in the port control register. 79 00:08:15,190 --> 00:08:31,810 So I'm going to load the register lowered our 1 e course GPA to a P C T L on the score register and 80 00:08:31,810 --> 00:08:35,680 then we're gonna take its content and put it into our 0 81 00:08:39,350 --> 00:08:49,690 and then we going to clear a bit using a b c instruction then we started resort back into our 0 we cleared 82 00:08:49,690 --> 00:08:51,460 a bit of what is in our 0 83 00:08:55,740 --> 00:09:01,490 cleared these using this hexadecimal number and then the resources put back into our issue we could 84 00:09:01,490 --> 00:09:05,910 use to appearance here if we want but I'm using our shoe. 85 00:09:05,950 --> 00:09:08,600 If I use just this is the same as this. 86 00:09:08,720 --> 00:09:15,410 So you need not worry so once that is done we're going to configure this uh the same bits we'll use 87 00:09:15,490 --> 00:09:19,090 and the results after clearing it's going to be put here. 88 00:09:19,190 --> 00:09:26,630 It's gonna point to our series so I'll see Iris you and and then I'm gonna configure 89 00:09:29,860 --> 00:09:35,530 P is your MP you want us you ut is the same I've seen Iris you Iris through the third opera and it's 90 00:09:35,680 --> 00:09:42,310 the destination in the case where you don't audit fed or print the second or print becomes the second 91 00:09:42,370 --> 00:09:45,320 or print as well as the destination. 92 00:09:45,490 --> 00:09:46,090 Right. 93 00:09:46,120 --> 00:09:56,860 So this this would do this for us did we deal with the alternate function register we've not dealt with 94 00:09:56,860 --> 00:10:02,590 that so I'm going to enable the alternate function register 95 00:10:06,570 --> 00:10:16,840 I'm gonna put that up here I'll see GPL you a alternate function select the what we want to do over 96 00:10:16,840 --> 00:10:27,250 here is set s p a zero and p a 1 to the ordinary functions so pass this here like this to do this in 97 00:10:27,250 --> 00:10:41,110 assembly 0 to load R 1 GPL you a lot and a function select register take the content and put it into 98 00:10:41,170 --> 00:10:41,890 Iris 0 99 00:10:45,840 --> 00:10:50,340 and then perform an operation 100 00:10:55,650 --> 00:10:59,390 with this and then store it back 101 00:11:02,980 --> 00:11:05,850 like this okay. 102 00:11:06,340 --> 00:11:06,750 Right. 103 00:11:06,760 --> 00:11:12,780 So once we're done with it we can start configuring the new art to configure the U. 104 00:11:12,790 --> 00:11:22,670 We start off by disabling it so we simply going to disable to you at we can just write to zero today 105 00:11:22,670 --> 00:11:26,460 you control register sort of everything in the register set to zero. 106 00:11:26,600 --> 00:11:33,620 We can just set a particular bit to enable disable it in the register to zero if we want to set a particular 107 00:11:33,680 --> 00:11:46,070 bits to zero we have to use the M B C instruction so let's do the start off by doing load our one with 108 00:11:46,070 --> 00:11:57,380 a you add control register you at zero c t o on the score R and then we're gonna take the content of 109 00:11:57,380 --> 00:12:06,920 the register and put it into our 0 and then we're gonna clear it by doing b c store the result in our 110 00:12:06,920 --> 00:12:17,400 zero take our 0 and then apply you to control enable which we've created a symbolic name for this one 111 00:12:17,400 --> 00:12:17,970 over here. 112 00:12:24,480 --> 00:12:25,040 Right. 113 00:12:25,090 --> 00:12:27,450 And then we store the results. 114 00:12:32,860 --> 00:12:35,030 Our 0 1 like this 115 00:12:38,010 --> 00:12:38,530 next. 116 00:12:38,600 --> 00:12:45,710 We configured the bot rate we're going to access the 2 bulk rate to registers the 1 for the integer 117 00:12:45,710 --> 00:12:47,810 part and the fractional part. 118 00:12:48,080 --> 00:12:52,700 So I'm gonna say load our 1 119 00:12:55,830 --> 00:13:02,980 portray to register in the name we gave it was it should be up here somewhere. 120 00:13:03,010 --> 00:13:03,760 Let's get a name 121 00:13:07,180 --> 00:13:14,860 there's the first one you at I P R T R This is the integer portraits register 122 00:13:18,070 --> 00:13:29,740 we load this first and then and then um and then we compute the bulk rate so to to the broke rate we 123 00:13:29,740 --> 00:13:38,750 have to divide our clock frequency by 16 multiplied by the board rate we want to use remember popular 124 00:13:38,780 --> 00:13:41,380 but rates that we often use include 125 00:13:46,040 --> 00:13:53,520 popular board rates include nine thousand six hundred one one five two hundred etc.. 126 00:13:53,810 --> 00:14:02,960 So to compute the value to put into the box rate in which I register the formula is to take our clock 127 00:14:02,960 --> 00:14:11,900 frequency the frequency of my MCU is sixteen figureheads mean 16 million or take this 16 million and 128 00:14:11,900 --> 00:14:18,740 then I would divide by sixteen multiplied by the portrait I want to use let's say I want a board rate 129 00:14:18,740 --> 00:14:27,650 of one thousand and fifteen one thousand fifteen and two hundred sorry one hundred and fifteen thousand 130 00:14:27,650 --> 00:14:34,490 two hundred let's say I want to board rate of one hundred fifteen thousand two hundred I'm going to 131 00:14:34,490 --> 00:14:42,800 compute this I'm going to do sixteen million divided by sixteen times one hundred and fifteen two hundred 132 00:14:42,830 --> 00:14:49,170 if I want this out put this here if I want a portrait of nine thousand six hundred multiply this system 133 00:14:49,190 --> 00:14:51,090 by this if my frequency is different. 134 00:14:51,090 --> 00:14:56,390 Leslie I'm running at fifty megaHertz I'll have to change the sixteen to fifty two how fifty million. 135 00:14:56,600 --> 00:14:59,980 But I'm run the sixteen megahertz This is a constant. 136 00:15:00,110 --> 00:15:04,560 So these are the two variables right. 137 00:15:05,030 --> 00:15:16,750 And when I compute this one you perform this calculation you get eight point six eight 0. 138 00:15:17,750 --> 00:15:19,410 So this is going to be the answer. 139 00:15:19,490 --> 00:15:21,790 This is the integer the integer between is 8. 140 00:15:21,800 --> 00:15:27,020 So we've got to take this 8 and put it into the integer both to register. 141 00:15:27,020 --> 00:15:27,440 Right. 142 00:15:28,580 --> 00:15:38,120 So what I'm going to do is move this to the to the register so I'm going to do I'm simply going to use 143 00:15:38,120 --> 00:15:54,610 the M the move instruction to achieve this oh do move move are zero the number eight and then I'll star 144 00:15:54,610 --> 00:16:02,310 it into the integer portraits register by doing so what is an ask you are 1 like this. 145 00:16:02,360 --> 00:16:08,000 Okay so now we've sorted out we've put just this eight How about a fraction politics it's not complete 146 00:16:08,480 --> 00:16:15,410 we're going to store a fraction part in the fraction register so I'm going to load that 147 00:16:18,570 --> 00:16:23,240 I'm going to do load R one equals 148 00:16:26,210 --> 00:16:34,070 you 0 F R D fraction board rate is F B T. 149 00:16:34,320 --> 00:16:45,320 Yeah on a school R and to compare it to the fraction part we'll use a different formula we take the 150 00:16:45,320 --> 00:16:52,790 French we take the this part here plus fractional number we multiply by sixty four and then zero point 151 00:16:52,790 --> 00:16:53,540 five. 152 00:16:53,690 --> 00:16:57,320 So we took what is left here that is gonna be 153 00:17:07,490 --> 00:17:16,410 this is going to be zero point six it's u of five multiplied by sixty four multiplied by zero point 154 00:17:16,410 --> 00:17:25,380 five and the answer we'll get to be forty four point zero five two. 155 00:17:25,710 --> 00:17:32,160 So this time we just take this as well we don't care about this last bit is fine so we're going to move 156 00:17:32,250 --> 00:17:34,770 forty four into register our zero 157 00:17:42,500 --> 00:17:43,990 and then we're going to store it. 158 00:17:55,340 --> 00:17:55,750 Right. 159 00:17:56,400 --> 00:18:02,290 So once this is done we have to set our um our wetlands. 160 00:18:02,300 --> 00:18:03,070 They pay to land. 161 00:18:03,070 --> 00:18:07,060 We want to use and we do it is by access the line control register. 162 00:18:07,990 --> 00:18:13,760 So I do know these are our one. 163 00:18:14,340 --> 00:18:26,790 I want a course you zero LC RH on a score are for register and then I'm going to do Delta. 164 00:18:26,810 --> 00:18:35,860 Ah I wish you would take the content and put into our receiver like this and then once we have that 165 00:18:37,930 --> 00:18:42,310 we're going to we're going to disable. 166 00:18:42,520 --> 00:18:45,040 We're going to clear all fields. 167 00:18:45,490 --> 00:18:53,410 Now we can do B C over here b c are as you are as you f f 168 00:18:56,610 --> 00:19:02,990 and once we've done that now we can set the with as well as enable. 169 00:19:03,000 --> 00:19:05,700 So I'm going to do at our zero end. 170 00:19:05,760 --> 00:19:11,110 Are you sorry and our zero hours zero 171 00:19:14,320 --> 00:19:20,590 and I'm going to get the symbolic name we've created here. 172 00:19:21,150 --> 00:19:21,810 I'll get this 173 00:19:25,740 --> 00:19:28,210 and then I'll include FIFO and naval as well. 174 00:19:28,400 --> 00:19:30,110 I'll get Fi for a. 175 00:19:30,570 --> 00:19:33,480 This one here. 176 00:19:33,480 --> 00:19:36,930 Bring it over here like this. 177 00:19:36,950 --> 00:19:43,470 Once that is done we can still use the stone instruction as the are r zero 178 00:19:47,520 --> 00:19:48,290 R 1. 179 00:19:49,780 --> 00:19:50,650 Okay. 180 00:19:50,650 --> 00:19:58,500 So finally all we have to do is enable it to you at because we disabled it when we start it. 181 00:19:58,750 --> 00:20:00,760 So we accessed the control register. 182 00:20:01,000 --> 00:20:10,460 Oh these are our one you at zero CTA L on the score. 183 00:20:12,400 --> 00:20:15,530 And then we move the content into register. 184 00:20:15,550 --> 00:20:17,320 Iris you were like this. 185 00:20:24,870 --> 00:20:26,110 And then with the form 1. 186 00:20:26,150 --> 00:20:26,940 Operation 187 00:20:30,130 --> 00:20:41,010 we created a symbolic name called U UT c t o u s e n. 188 00:20:41,670 --> 00:20:42,300 Right. 189 00:20:42,330 --> 00:20:45,570 And then we can store our 0 190 00:20:49,460 --> 00:20:49,920 r 1. 191 00:20:50,370 --> 00:20:50,740 OK. 192 00:20:50,750 --> 00:20:57,580 So because we pushed the link register when we started we've got a pop it gonna pop. 193 00:21:00,410 --> 00:21:01,350 LA um. 194 00:21:01,370 --> 00:21:01,750 Got it. 195 00:21:02,790 --> 00:21:03,660 I'm going to 196 00:21:08,860 --> 00:21:11,030 I'm gonna pop the LR here. 197 00:21:11,380 --> 00:21:12,740 Let's see. 198 00:21:12,880 --> 00:21:13,080 Yeah. 199 00:21:19,830 --> 00:21:22,950 Okay so this is going to be uh. 200 00:21:24,210 --> 00:21:27,500 There's gonna be a uh you out initialization subroutine. 201 00:21:28,200 --> 00:21:36,730 So the next thing we've got to do is create other subroutines for um for reading and write and data. 202 00:21:36,780 --> 00:21:37,210 Okay. 203 00:21:37,230 --> 00:21:38,940 So let's do that in the next lesson.