projects / sigrok-firmware-fx2lafw.git / blame
| Commit | Line | Data |
|---|---|---|
| 3608c106 UH |
1 | /** |
| 2 | * Copyright (C) 2009 Ubixum, Inc. | |
| 3 | * | |
| 4 | * This library is free software; you can redistribute it and/or | |
| 5 | * modify it under the terms of the GNU Lesser General Public | |
| 6 | * License as published by the Free Software Foundation; either | |
| 7 | * version 2.1 of the License, or (at your option) any later version. | |
| 8 | * | |
| 9 | * This library is distributed in the hope that it will be useful, | |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 12 | * Lesser General Public License for more details. | |
| 13 | * | |
| 14 | * You should have received a copy of the GNU Lesser General Public | |
| 15 | * License along with this library; if not, write to the Free Software | |
| 16 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
| 17 | **/ | |
| 18 | ||
| 19 | ||
| 20 | #include <fx2regs.h> | |
| 21 | #include <fx2macros.h> | |
| 22 | #include <serial.h> | |
| 23 | ||
| 24 | ||
| 25 | /** | |
| 26 | * using the comp port implies that timer 2 will be used as | |
| 27 | * a baud rate generator. (Don't use timer 2) | |
| 28 | **/ | |
| 29 | void sio0_init( WORD baud_rate ) __critical { // baud_rate max should be 57600 since int=2 bytes | |
| 30 | ||
| 31 | WORD hl; // hl value for reload | |
| 32 | BYTE mult; // multiplier for clock speed | |
| 33 | DWORD tmp; // scratch for mult/divide | |
| 34 | ||
| 35 | // 0 = 12mhz, 1=24mhz, 2=48mhz | |
| 36 | mult = CPUFREQ == CLK_12M ? 1 : | |
| 37 | CPUFREQ == CLK_24M ? 2 : 4; // since only 3 clock speeds, fast switch instead of doing 2^clock speed pow(2,clkspd) | |
| 38 | ||
| 39 | // set the clock rate | |
| 40 | // use clock 2 | |
| 41 | RCLK=1;TCLK=1; | |
| 42 | ||
| 43 | // RCAP2H:L = 0xFFFF - CLKOUT / 32 x baud_rate | |
| 44 | ||
| 45 | // in order to round to nearest value.. | |
| 46 | // tmp * 2 // double | |
| 47 | // tmp / rate // do the divide | |
| 48 | // tmp + 1 // add one (which is like adding 1/2) | |
| 49 | // tmp / 2 // back to original rounded | |
| 50 | tmp = mult * 375000L * 2 ; | |
| 51 | tmp /= baud_rate; | |
| 52 | tmp += 1; | |
| 53 | tmp /= 2; | |
| 54 | ||
| 55 | hl = 0xFFFF - (WORD)tmp; | |
| 56 | ||
| 57 | RCAP2H= MSB(hl); | |
| 58 | // seems that the 24/48mhz calculations are always one less than suggested values | |
| 59 | // trm table 14-16 | |
| 60 | RCAP2L= LSB(hl) + (mult>0?1:0); | |
| 61 | TR2=1; // start the timer | |
| 62 | ||
| 63 | // set up the serial port | |
| 64 | SM0 = 0; SM1=1;// serial mode 1 (asyncronous) | |
| 65 | SM2 = 0 ; // has to do with receiving | |
| 66 | REN = 1 ; // to enable receiving | |
| 67 | PCON |= 0x80; // SET SMOD0, baud rate doubler | |
| 68 | TI = 1; // we send initial byte | |
| 69 | ||
| 70 | } | |
| 71 | ||
| 72 | char getchar() { | |
| 73 | char c; | |
| 74 | while (!RI) | |
| 75 | ; | |
| 76 | c=SBUF0; | |
| 77 | RI=0; | |
| 78 | return c; | |
| 79 | } | |
| 80 | ||
| 81 | void _transchar(char c) { | |
| 82 | while ( !TI ); // wait for TI=1 | |
| 83 | TI=0; | |
| 84 | SBUF0=c; | |
| 85 | } | |
| 86 | ||
| 87 | void putchar (char c) { | |
| 88 | if (c=='\n') _transchar('\r'); // transmit \r\n | |
| 89 | _transchar(c); | |
| 90 | if (c == '\r' ) _transchar('\n'); // transmit \r\n | |
| 91 | } | |
| 92 |