Bit-Toggle Benchmark with GCC

A single bit (digital output port) is toggled by software as fast as possible. The other bits of the port are not affected. Programming is in ANSI-C with the C-compilers ECO-C-11, WinECO-C and ECO-C-arm.

Targets

SBC	Controller	Clock	Program Memory	C-Source
IC11B	MC68HC11A1 (HC11)	2MHz	8Bit Data bus ext. RAM	view
ZWERG332A	MC68332 (CPU32)	25MHz	8Bit Data bus ext. RAM	view
MEGA332A	MC68332 (CPU32)	25MHz	16Bit Data bus ext. RAM or fast termination ext. RAM	view
LC7024	AduC7024 (ARM7)	45MHz	16Bit Data bus int. FLASH	view
NET2106	LPC2106 (ARM7)	60MHz	32Bit Data bus int. FLASH	view
S2103	LPC2103 (ARM7)	70MHz	32Bit Data bus int. FLASH	view

Results

SBC	Periode	Frequency	Oscillogram	Assembleroutput C-Compiler
IC11B	8.5us	0.117MHz	view	view
ZWERG332A	1.28us	0.819MHz	view	view
MEGA332A fast termination	1.12us 1us	0.892MHz 1MHz	view view	view
LC7024	0.6us	1.66MHz	view	view
NET2106	0.29us	3.45MHz	view	view
S2103	0.1us	10MHz	view	view

Conclusions

The output frequency depends on the processor clock and the access times to the program memory. The LPC2106 has an advantage because of its very fast access to the internal FLASH.

The system performance however is application-dependent. Special hardware like the timer system, PWM outputs etc. can free the CPU considerably and so increase the overall performance significantly.

The MC68332 is almost a multi-processor system. The TPU can, for example, independently control motors and process quadrature encoder information.

www.mct.net