Interface Overview
11-4
ADSP-BF537 Blackfin Processor Hardware Reference
In master mode the TWI controller must set this signal to the desired fre-
quency. The TWI controller supports the standard mode of operation (up
to 100 KHz) or fast mode (up to 400 KHz).
The TWI control register (
TWI_CONTROL
) is used to set the
PRESCALE
value
which gives the relationship between the system clock (
SCLK
) and the TWI
controller’s internally timed events. The internal time reference is derived
from
SCLK
using a prescaled value.
PRESCALE
=
f
SCLK
/
10MHz
The
PRESCALE
value is the number of system clock (
SCLK
) periods used in
the generation of one internal time reference. The value of
PRESCALE
must
be set to create an internal time reference with a period of 10 MHz. It is
represented as a 7-bit binary value.
Serial data signal (SDA)
This is a bidirectional signal on which serial data is transmitted or received
depending on the direction of the transfer.
TWI Pins
shows the pins for the TWI. Two bidirectional pins externally
interface the TWI controller to the I
2
C bus. The interface is simple and
no other external connections or logic are required.
Table 11-1. TWI Pins
Pin
Description
SDA
In/Out TWI serial data, high impedance reset value.
SCL
In/Out TWI serial clock, high impedance reset value.
Summary of Contents for Blackfin ADSP-BF537
Page 42: ...Contents xlii ADSP BF537 Blackfin Processor Hardware Reference ...
Page 90: ...Development Tools 1 32 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 138: ...Programming Examples 4 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 340: ...SDC Programming Examples 6 84 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 606: ...Programming Examples 9 94 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 660: ...Programming Examples 10 54 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 720: ...Electrical Specifications 11 60 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 840: ...Programming Examples 13 42 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 876: ...Programming Examples 14 36 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 938: ...Programming Examples 15 62 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 958: ...Programming Examples 17 12 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 986: ...Programming Examples 18 28 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1162: ...G 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1218: ...Index I 56 ADSP BF537 Blackfin Processor Hardware Reference ...