Fast I2C & Smbus - Kontron COMe-mSP1 User Manual

4.5 Fast I2C & SMBus
The COMe-mSP1 integrates two configurable I2C buses. The external I2C provided via US15W GPIOs on COM Express®
Connector Pin B33/B34, the LVDS I2C from US15W SCH is available on COM express® connector pin A83/A84. The I2C
interface offers full MultiMaster and Clock Stretching support. Fast I2C and SMBus clock speed depends on the CPU
performance and differs between ATOM™ Z510 and ATOM™ Z530 modules. See the tables below for measured values on
COMe-mSP1 with BIOS NOW1R118.
JIDA/external I2C speed
JIDA/external I2C speed
Setup ATOM™ Z510
Extra high not supported
Very high 166 kHz
High 80 kHz
Medium 41 kHz
Slow 10 kHz
Very slow 1 kHz
Ultra slow 0.7 kHz
31
ATOM™ Z530 ATOM™ Z510
not supported not supported
215 kHz 80 kHz
110 kHz 55 kHz
60 kHz 34 kHz
15 kHz 9.6 kHz
2 kHz 1.5 kHz
1 kHz not supported
COMe-mSP1 / Features and Interfaces
JILI I2C speed
ATOM™ Z530 ATOM™ Z510
not supported 375 kHz
125 kHz 214 kHz
80 kHz 57 kHz
50 kHz 35 kHz
15 kHz 7.4 kHz
2 kHz 0.7 kHz
not supported not supported
SMBus speed
ATOM™ Z530
418 kHz
270 kHz
86 kHz
46 kHz
10 kHz
1 kHz
not supported