I use strcpy because I want the string to be in one line, puts does a new line.
That makes sense. I had forgotten about puts() adding a newline at the end. I often write my own routines for microcontrollers rather than use stdio.h routines to reduce compiled size, and my string printing routine doesn't add a newline.
I don't know how much space itoa is taking, but here is the routine I use for printing integers with a fixed width when I know the width. Adjust the mask for the max number of digits your value will ever have (eg. 100 for 3 digit numbers). SendChar() is my routine to send a single character (over the serial port).
Code: Select all
// Send a word (16-bits, 5 digits with leading 0s)
void SendWord(uint16_t w) {
uint16_t mask = 10000;
while (mask) {
SendChar('0'+(w/mask));
w %= mask;
mask/=10;
}
return;
}
While % and / are expensive operations, you are likely already paying that price with the code in itoa(). It's also possible to write it without division like this snippet that I found in my collection of junk that I wrote a long time ago - which certainly has
lots of room for optimization:
Code: Select all
void SendByte(unsigned char b) {
unsigned char mask = 100;
unsigned char digit;
// 100s digit.
digit = '0';
while(b >= mask)
{
digit++;
b = b - mask;
}
SendChar(digit);
// 10s digit.
mask = 10;
digit = '0';
while(b >= mask)
{
digit++;
b = b - mask;
}
SendChar(digit);
// 1s digit.
mask = 1;
digit = '0';
while(b >= mask)
{
digit++;
b = b - mask;
}
SendChar(digit);
return;
}
As for the K&R syntax, it started as a retro thing, then I quickly realized that the default C engine (or only engine) for cc65 is c89, which is wild to me.
I also did the k&r syntax so Aztec C can compile it natively for CP/M and Apple II, if you want!
So not just a retro feel, but actually compatible with retro compilers. That gets you bonus points, of course!
I heard in the past that the target was a 68K dev board. When I took the class the target was a PC booted from a floppy as a boot loader for the OS transferred over the serial port. The dev environment was a PC running linux.
