HT45R37V Holtek Semiconductor Inc., HT45R37V Datasheet - Page 43

• Manufacturer Part Number: HT45R37V
• Description: C/r-f Type 8-bit Otp Mcu
• Manufacturer: Holtek Semiconductor Inc.

The status of the SPI interface pins is determined by a
number of factors such as whether the device is in the
master or slave mode and upon the condition of certain
control bits such as CSEN, SIMEN and SCS. In the table
I, Z represents an input floating condition.
There are several configuration options associated with
the SPI interface. One of these is to enable the SIM
function which selects the SIM pins rather than normal
I/O pins. Note that if the configuration option does not
select the SIM function then the SIMEN bit in the
SIMCTL0 register will have no effect. Another two SIM
configuration options determine if the CSEN and WCOL
bits are to be used.
Note:
Rev. 1.00
SDO
SCS
SCK
SDI
Pin
LSB first or MSB first data transmission modes
Transmission complete flag
Rising or falling active clock edge
WCOL and CSEN bit enabled or disable select
Z floating, H output high, L output low, I Input, O output level, I,Z input floating (no pull-high)
Master/Salve
SIMEN=0
Z
Z
Z
Z
H: CKPOL=0
L: CKPOL=1
CSEN=0
I, Z
Master - SIMEN=1
O
Z
SPI Interface Pin Status
H: CKPOL=0
L: CKPOL=1
SPI Block Diagram
CSEN=1
I, Z
O
L
43
SPI Registers
There are three internal registers which control the over-
all operation of the SPI interface. These are the SIMDR
data register and two control registers SIMCTL0 and
SIMCTL2. Note that the SIMCTL1 register is only used
by the I
Configuration Option
SIM Function
SPI CSEN bit
SPI WCOL bit
CSEN=0
2
C interface.
SPI Interface Configuration Options
I, Z
I, Z
O
Z
Slave - SIMEN=1
CSEN=1
SCS=0
SIM interface enable/disable
Enable/Disable
Enable/Disable
I, Z
I, Z
I, Z
O
Function
October 20, 2009
HT45R37V
CSEN=1
SCS=1
I, Z
Z
Z
Z