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Add Buffer.get/setNumber and i2c methods

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This commit is contained in:
Michal Moskal
2016-04-04 19:02:40 -07:00
parent 61fd28d840
commit bd7430b642
6 changed files with 174 additions and 18 deletions
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78
libs/microbit/buffer.cpp
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@ -1,5 +1,19 @@
#include "ksbit.h"
enum class NumberFormat {
Int8LE = 1,
UInt8LE,
Int16LE,
UInt16LE,
Int32LE,
Int8BE,
UInt8BE,
Int16BE,
UInt16BE,
Int32BE,
// UInt32,
};
//% indexerGet=BufferMethods::getByte indexerSet=BufferMethods::setByte
namespace BufferMethods {
//%
@ -17,6 +31,70 @@ namespace BufferMethods {
return buf->payload;
}
/**
* Write a number in specified format in the buffer.
*/
//%
void setNumber(Buffer buf, NumberFormat format, int offset, int value)
{
int8_t i8;
uint8_t u8;
int16_t i16;
uint16_t u16;
int32_t i32;
ManagedBuffer b(buf);
// Assume little endian
#define WRITEBYTES(isz, swap) isz = value; b.writeBytes(offset, (uint8_t*)&isz, sizeof(isz), swap); break
switch (format) {
case NumberFormat::Int8LE: WRITEBYTES(i8, false);
case NumberFormat::UInt8LE: WRITEBYTES(u8, false);
case NumberFormat::Int16LE: WRITEBYTES(i16, false);
case NumberFormat::UInt16LE: WRITEBYTES(u16, false);
case NumberFormat::Int32LE: WRITEBYTES(i32, false);
case NumberFormat::Int8BE: WRITEBYTES(i8, true);
case NumberFormat::UInt8BE: WRITEBYTES(u8, true);
case NumberFormat::Int16BE: WRITEBYTES(i16, true);
case NumberFormat::UInt16BE: WRITEBYTES(u16, true);
case NumberFormat::Int32BE: WRITEBYTES(i32, true);
}
}
/**
* Read a number in specified format from the buffer.
*/
//%
int getNumber(Buffer buf, NumberFormat format, int offset)
{
int8_t i8;
uint8_t u8;
int16_t i16;
uint16_t u16;
int32_t i32;
ManagedBuffer b(buf);
// Assume little endian
#define READBYTES(isz, swap) b.readBytes((uint8_t*)&isz, offset, sizeof(isz), swap); return isz
switch (format) {
case NumberFormat::Int8LE: READBYTES(i8, false);
case NumberFormat::UInt8LE: READBYTES(u8, false);
case NumberFormat::Int16LE: READBYTES(i16, false);
case NumberFormat::UInt16LE: READBYTES(u16, false);
case NumberFormat::Int32LE: READBYTES(i32, false);
case NumberFormat::Int8BE: READBYTES(i8, true);
case NumberFormat::UInt8BE: READBYTES(u8, true);
case NumberFormat::Int16BE: READBYTES(i16, true);
case NumberFormat::UInt16BE: READBYTES(u16, true);
case NumberFormat::Int32BE: READBYTES(i32, true);
}
return 0;
}
/** Returns the length of a Buffer object. */
//% property
int length(Buffer s) {