Rev. 1.50 130 August 28, 2017 Rev. 1.50 131 August 28, 2017
HT66F0175/HT66F0185
A/D Flash MCU with EEPROM
HT66F0175/HT66F0185
A/D Flash MCU with EEPROM
SPI Master/Slave Connection
SPI Block Diagram
SPI Registers
TherearethreeinternalregisterswhichcontroltheoveralloperationoftheSPIinterface.Theseare
theSIMDdataregisterandtworegistersSIMC0andSIMC2.NotethattheSIMC1registerisonly
usedbytheI
2
Cinterface.
Register
Name
Bit
7 6 5 4 3 2 1 0
SIMC0 SIM2 SIM1 SIM0 — SIMDEB1 SIMDEB0 SIMEN SIMICF
SIMC2 D7 D6 CKPOLB CKEG MLS CSEN WCOL TRF
SIMD D7 D6 D5 D4 D3 D2 D1 D0
SPI Registers List
SIMD Register
TheSIMDregisterisusedtostorethedatabeingtransmittedandreceived.Thesameregisterisused
byboththeSPIandI
2
Cfunctions.BeforethedeviceswritedatatotheSPIbus,theactualdatato
betransmittedmustbeplacedintheSIMDregister.AfterthedataisreceivedfromtheSPIbus,the
devicecanreaditfromtheSIMDregister.AnytransmissionorreceptionofdatafromtheSPIbus
mustbemadeviatheSIMDregister.
Bit 7 6 5 4 3 2 1 0
Name D7 D6 D5 D4 D3 D2 D1 D0
R/W R/W R/W R/W R/W R/W R/W R/W R/W
POR x x x x x x x x
“x”: unknown