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    "# 8051 Calculations for Baud Rate Generator\n",
    "\n",
    "Desired baud rate is 9600. What oscillator frequencies and timer settings can we use in order to generate that baud rate with acceptable error?\n",
    "\n",
    "$BaudRate = \\frac{K \\;\\times\\; OscillatorFreq}{32 \\;\\times\\; 12 \\;\\times\\; (256 - TH1)}$\n",
    "\n",
    "$TH1 = 256 - \\frac{K \\;\\times\\; OscillatorFreq}{32 \\;\\times\\; 12 \\;\\times\\; BaudRate}$\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
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       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>F (MHz)</th>\n",
       "      <th>K</th>\n",
       "      <th>TH1</th>\n",
       "      <th>Baud</th>\n",
       "      <th>% Error</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>1.843200</td>\n",
       "      <td>2</td>\n",
       "      <td>255</td>\n",
       "      <td>9600.000000</td>\n",
       "      <td>0.000000</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>3.579545</td>\n",
       "      <td>1</td>\n",
       "      <td>255</td>\n",
       "      <td>9321.731771</td>\n",
       "      <td>-2.898627</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>3.579545</td>\n",
       "      <td>2</td>\n",
       "      <td>254</td>\n",
       "      <td>9321.731771</td>\n",
       "      <td>-2.898627</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>3.686400</td>\n",
       "      <td>1</td>\n",
       "      <td>255</td>\n",
       "      <td>9600.000000</td>\n",
       "      <td>0.000000</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>3.686400</td>\n",
       "      <td>2</td>\n",
       "      <td>254</td>\n",
       "      <td>9600.000000</td>\n",
       "      <td>0.000000</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>7.372800</td>\n",
       "      <td>1</td>\n",
       "      <td>254</td>\n",
       "      <td>9600.000000</td>\n",
       "      <td>0.000000</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>7.372800</td>\n",
       "      <td>2</td>\n",
       "      <td>252</td>\n",
       "      <td>9600.000000</td>\n",
       "      <td>0.000000</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>11.059200</td>\n",
       "      <td>1</td>\n",
       "      <td>253</td>\n",
       "      <td>9600.000000</td>\n",
       "      <td>0.000000</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>11.059200</td>\n",
       "      <td>2</td>\n",
       "      <td>250</td>\n",
       "      <td>9600.000000</td>\n",
       "      <td>0.000000</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "     F (MHz)  K  TH1         Baud   % Error\n",
       "0   1.843200  2  255  9600.000000  0.000000\n",
       "1   3.579545  1  255  9321.731771 -2.898627\n",
       "2   3.579545  2  254  9321.731771 -2.898627\n",
       "3   3.686400  1  255  9600.000000  0.000000\n",
       "4   3.686400  2  254  9600.000000  0.000000\n",
       "5   7.372800  1  254  9600.000000  0.000000\n",
       "6   7.372800  2  252  9600.000000  0.000000\n",
       "7  11.059200  1  253  9600.000000  0.000000\n",
       "8  11.059200  2  250  9600.000000  0.000000"
      ]
     },
     "execution_count": 4,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "import pandas as pd\n",
    "\n",
    "# Available oscillator frequencies <= 12 MHz\n",
    "Flist = [\n",
    "    1.0E6,\n",
    "    1.2288E6,\n",
    "    1.544E6,\n",
    "    1.8432E6,\n",
    "    2.0E6,\n",
    "    2.5476E6,\n",
    "    2.2768E6,\n",
    "    3.579545E6,\n",
    "    3.6864E6,\n",
    "    4.0E6,\n",
    "    4.096E6,\n",
    "    4.9152E6,\n",
    "    5.0E6,\n",
    "    5.0688E6,\n",
    "    6.0E6,\n",
    "    6.144E6,\n",
    "    7.3728E6,\n",
    "    8.0E6,\n",
    "    9.8304E6,\n",
    "    10.0E6,\n",
    "    11.0592E6,\n",
    "    12.0E6\n",
    "]\n",
    "\n",
    "# Multipliers for SMOD = (0,1)\n",
    "Klist = [1, 2]\n",
    "\n",
    "# Target baud rate\n",
    "Btarget = 9600\n",
    "\n",
    "# Calculate TH1 setting, actual baud rate, and error\n",
    "tbl = []\n",
    "for F in Flist:\n",
    "    for K in Klist:\n",
    "        TH1  = int(256 - (K * F)/(32 * 12 * Btarget))\n",
    "        if TH1 > 0:\n",
    "            Bactual = (K * F)/(32 * 12 * (256 - TH1))\n",
    "            Berror  = 100.0*(Bactual - Btarget)/Btarget\n",
    "            if abs(Berror) <= 5.0:\n",
    "                tbl.append([F/1.0E6, K, TH1, Bactual, Berror])\n",
    "pd.DataFrame(tbl, columns=['F (MHz)', 'K', 'TH1', 'Baud', '% Error'])\n",
    "\n",
    "        "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
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