diff --git a/gcode_parse.c b/gcode_parse.c index 43df42e..e2c16f7 100644 --- a/gcode_parse.c +++ b/gcode_parse.c @@ -32,54 +32,43 @@ GCODE_COMMAND next_target __attribute__ ((__section__ (".bss"))); decfloat_to_int() is the weakest subject to variable overflow. For evaluation, we assume a build room of +-1000 mm and STEPS_PER_MM_x between 1.000 and 4096. Accordingly for metric units: df->mantissa: +-0..1048075 (20 bit - 500 for rounding) - df->exponent: 0, 2, 3 or 4 (10 bit) - multiplicand / denominator: 20..4194303 / 1000 (22 bit - 10 bit) or - 0..4095 / 1 (12 bit - 0 bit) + df->exponent: 0, 2, 3, 4 or 5 (10 bit) + multiplicand: 1000 (10 bit) imperial units: df->mantissa: +-0..32267 (15 bit - 500 for rounding) - df->exponent: 0, 2, 3 or 4 (10 bit) - multiplicand: 1..105000 (17 bit) - denominator: 1 or 10 ( 4 bit) + df->exponent: 0, 2, 3, 4 or 5 (10 bit) + multiplicand: 25400 (15 bit) */ -// accordingly: -#define DECFLOAT_EXP_MAX 4 -#define DECFLOAT_MANT_MM_MAX 1048075 -#define DECFLOAT_MANT_IN_MAX 32267 +// decfloat_to_int() can handle a bit more: +#define DECFLOAT_EXP_MAX 3 // more is pointless, as 1 um is our presision +// (2^^32 - 1) / multiplicand - powers[DECFLOAT_EXP_MAX] / 2 = +// 4294967295 / 1000 - 5000 = +#define DECFLOAT_MANT_MM_MAX 4289967 // = 4290 mm +// 4294967295 / 25400 - 5000 = +#define DECFLOAT_MANT_IN_MAX 164093 // = 164 inches = 4160 mm /* utility functions */ extern const uint32_t powers[]; // defined in sermsg.c -// TODO: When the new approach to pass distances in micrometers instead of step -// numbers stays, this should be replaced by a simplified version. /// convert a floating point input value into an integer with appropriate scaling. /// \param *df pointer to floating point structure that holds fp value to convert /// \param multiplicand multiply by this amount during conversion to integer /// \param divide_by_1000 divide by 1000 during conversion to integer /// /// lots of work has been done in exploring this function's limitations in terms of overflow and rounding -/// this work may not be finished -static int32_t decfloat_to_int(decfloat *df, uint32_t multiplicand, uint8_t divide_by_1000) { +static int32_t decfloat_to_int(decfloat *df, uint32_t multiplicand) { uint32_t r = df->mantissa; uint8_t e = df->exponent; - uint32_t rnew1, rnew2; // e=1 means we've seen a decimal point but no digits after it, and e=2 means we've seen a decimal point with one digit so it's too high by one if not zero if (e) e--; - if (divide_by_1000) { - rnew1 = r * (multiplicand / 1000); - rnew2 = (r * (multiplicand % 1000) + (1000 / 2)) / 1000; - r = rnew1 + rnew2; - } - else { - r *= multiplicand; - } - + r *= multiplicand; if (e) r = (r + powers[e] / 2) / powers[e]; @@ -111,42 +100,42 @@ void gcode_parse_char(uint8_t c) { break; case 'X': if (next_target.option_inches) - next_target.target.X = decfloat_to_int(&read_digit, 25400, 1); + next_target.target.X = decfloat_to_int(&read_digit, 25400); else - next_target.target.X = decfloat_to_int(&read_digit, 1000, 0); + next_target.target.X = decfloat_to_int(&read_digit, 1000); if (DEBUG_ECHO && (debug_flags & DEBUG_ECHO)) serwrite_int32(next_target.target.X); break; case 'Y': if (next_target.option_inches) - next_target.target.Y = decfloat_to_int(&read_digit, 25400, 1); + next_target.target.Y = decfloat_to_int(&read_digit, 25400); else - next_target.target.Y = decfloat_to_int(&read_digit, 1000, 0); + next_target.target.Y = decfloat_to_int(&read_digit, 1000); if (DEBUG_ECHO && (debug_flags & DEBUG_ECHO)) serwrite_int32(next_target.target.Y); break; case 'Z': if (next_target.option_inches) - next_target.target.Z = decfloat_to_int(&read_digit, 25400, 1); + next_target.target.Z = decfloat_to_int(&read_digit, 25400); else - next_target.target.Z = decfloat_to_int(&read_digit, 1000, 0); + next_target.target.Z = decfloat_to_int(&read_digit, 1000); if (DEBUG_ECHO && (debug_flags & DEBUG_ECHO)) serwrite_int32(next_target.target.Z); break; case 'E': if (next_target.option_inches) - next_target.target.E = decfloat_to_int(&read_digit, 25400, 1); + next_target.target.E = decfloat_to_int(&read_digit, 25400); else - next_target.target.E = decfloat_to_int(&read_digit, 1000, 0); + next_target.target.E = decfloat_to_int(&read_digit, 1000); if (DEBUG_ECHO && (debug_flags & DEBUG_ECHO)) serwrite_uint32(next_target.target.E); break; case 'F': // just use raw integer, we need move distance and n_steps to convert it to a useful value, so wait until we have those to convert it if (next_target.option_inches) - next_target.target.F = decfloat_to_int(&read_digit, 25400, 1); + next_target.target.F = decfloat_to_int(&read_digit, 25400); else - next_target.target.F = decfloat_to_int(&read_digit, 1, 0); + next_target.target.F = decfloat_to_int(&read_digit, 1); if (DEBUG_ECHO && (debug_flags & DEBUG_ECHO)) serwrite_uint32(next_target.target.F); break; @@ -155,17 +144,17 @@ void gcode_parse_char(uint8_t c) { // cosmetically this should be done in the temperature section, // but it takes less code, less memory and loses no precision if we do it here instead if ((next_target.M == 104) || (next_target.M == 109) || (next_target.M == 140)) - next_target.S = decfloat_to_int(&read_digit, 4, 0); + next_target.S = decfloat_to_int(&read_digit, 4); // if this is heater PID stuff, multiply by PID_SCALE because we divide by PID_SCALE later on else if ((next_target.M >= 130) && (next_target.M <= 132)) - next_target.S = decfloat_to_int(&read_digit, PID_SCALE, 0); + next_target.S = decfloat_to_int(&read_digit, PID_SCALE); else - next_target.S = decfloat_to_int(&read_digit, 1, 0); + next_target.S = decfloat_to_int(&read_digit, 1); if (DEBUG_ECHO && (debug_flags & DEBUG_ECHO)) serwrite_uint16(next_target.S); break; case 'P': - next_target.P = decfloat_to_int(&read_digit, 1, 0); + next_target.P = decfloat_to_int(&read_digit, 1); if (DEBUG_ECHO && (debug_flags & DEBUG_ECHO)) serwrite_uint16(next_target.P); break; @@ -175,12 +164,12 @@ void gcode_parse_char(uint8_t c) { serwrite_uint8(next_target.T); break; case 'N': - next_target.N = decfloat_to_int(&read_digit, 1, 0); + next_target.N = decfloat_to_int(&read_digit, 1); if (DEBUG_ECHO && (debug_flags & DEBUG_ECHO)) serwrite_uint32(next_target.N); break; case '*': - next_target.checksum_read = decfloat_to_int(&read_digit, 1, 0); + next_target.checksum_read = decfloat_to_int(&read_digit, 1); if (DEBUG_ECHO && (debug_flags & DEBUG_ECHO)) serwrite_uint8(next_target.checksum_read); break; @@ -276,7 +265,7 @@ void gcode_parse_char(uint8_t c) { default: // can't do ranges in switch..case, so process actual digits here. if (c >= '0' && c <= '9') { - if (read_digit.exponent < DECFLOAT_EXP_MAX && + if (read_digit.exponent < DECFLOAT_EXP_MAX + 1 && ((next_target.option_inches == 0 && read_digit.mantissa < DECFLOAT_MANT_MM_MAX) || (next_target.option_inches &&