ISA3 Ember, ISA3 Datasheet - Page 94

• Manufacturer Part Number: ISA3
• Description: INSIGHT ADAPTER 3 FOR EM35X
• Manufacturer: Ember

Specifications of ISA3

• Accessory Type: Adapter
• For Use With/related Products: EM35x
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 636-1022

EXP is the value written to the SCx_RATEEXP register and LIN is the value written to the SCx_RATELIN register.
Table 8-8 shows the rate settings for Standard-Mode TWI (100 kbps) and Fast-Mode TWI (400 kbps) operation.
Note: At 400 kbps, the Philips I
on the EM35x it is 1.25 µs. If a slave device requires strict compliance with SCL timing, the clock rate must be
lowered to 375 kbps.
The EM35x supports clock stretching. The slave device can hold SCL low on any received or transmitted data
bit. This inhibits further data transfers until SCL is allowed to go high again.
8.5.3
The TWI master controller supports generating various frame segments by means of the SC_TWISTART,
SC_TWISTOP, SC_TWISEND, and SC_TWIRECV bits in the SCx_TWICTRL1 registers. Table 8-9 summarizes these
frames.
Constructing Frames
Clock Rate
100 kbps
375 kbps
400 kbps
2
C Bus specification requires the minimum low period of SCL to be 1.3 µs, but
Table 8-8. TWI Clock Rate Programming
Final
8-19
SCx_RATELIN
14
15
14
EM351 / EM357
SCx_RATEEXP
3
1
1
120-035X-000G