| ??? 06/27/05 13:01 Read: times |
#96011 - Keil Test Responding to: ???'s previous message |
I tested the Keil C51 compiler with the code block that I previously showed as working for the IAR compiler. I found it to work the same way producing reasonable integer constants.
Here is the code I fed into the Keil C51 compiler:
#pragma SRC
#define AD_REF 3.0 // A/D converter reference voltage
#define AD_CNT_RANGE 1024.0 // count range of the A/D converter
#define VIN_R1 47.5E3 // value of upper resistor in the VIN divider
#define VIN_R2 10.0E3 // value of lower resistor in the VIN divider
#define VIN_OFF 0.3 // VIN drop through diode to the VIN divider
#define VIN_MIN 6.5 // minimum VIN volts for device operation
#define VIN_MAX 13.5 // maximum VIN volts for device operation
#define VIN_HYS 0.2 // hystersis of VIN voltage for recovery
#define VIN_MIN_CNT ((unsigned int)(((((VIN_MIN - VIN_OFF) * VIN_R2)/(VIN_R1 + VIN_R2))*AD_CNT_RANGE)/AD_REF))
#define VIN_MAX_CNT ((unsigned int)(((((VIN_MAX - VIN_OFF) * VIN_R2)/(VIN_R1 + VIN_R2))*AD_CNT_RANGE)/AD_REF))
#define VIN_HYS_CNT ((unsigned int)((((VIN_HYS * VIN_R2)/(VIN_R1 + VIN_R2))*AD_CNT_RANGE)/AD_REF))
unsigned int code cnt_array[3] = {
VIN_MIN_CNT,
VIN_MAX_CNT,
VIN_HYS_CNT
};
The compiler produced the following SRC output: ; FloatDefs.SRC generated from: FloatDefs.c ; COMPILER INVOKED BY: ; C:KeilC51BINC51.EXE FloatDefs.c BROWSE DEBUG OBJECTEXTEND NAME FLOATDEFS ?CO?FLOATDEFS SEGMENT CODE PUBLIC cnt_array RSEG ?CO?FLOATDEFS cnt_array: DW 00170H DW 0030FH DW 0000BH ; #pragma SRC >- snip-< ; ( original source code copy snipped out ) >- snip-< END Here is the circuit diagram concept that the above code was used with. An onboard A/D converter on the microcontroller monitored the input voltage as being in the proper range so as to provide safe device operation when in range and lockout when out of range.  Michael Karas |
