ST & T UPSD3212C Computer Hardware User Manual


 
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uPSD3212A, uPSD3212C, uPSD3212CV
Address Register (S2ADR)
This 8-bit register may be loaded with the 7-bit
slave address to which the controller will respond
when programmed as a slave receive/transmitter.
The Start/Stop Hold Time Detection and System
Clock registers (Tables 57 and 58) are included in
the I
2
C unit to specify the start/stop detection time
to work with the large range of MCU frequency val-
ues supported. For example, with a system clock
of 40MHz.
Table 56. Address Register (S2ADR)
Note: SLA6 to SLA0: Own slave address.
Table 57. Start /Stop Hold Time Detection Register (S2SETUP)
Table 58. System Cock of 40MHz
Table 59. System Clock Setup Examples
76543210
SLA6 SLA5 SLA4 SLA3 SLA2 SLA1 SLA0
Address Register Name Reset Value Note
SFR D2h S2SETUP 00h
To control the start/stop hold time detection for the multi-master
I²C module in Slave Mode
S1SETUP,
S2SETUP Register
Value
Number of Sample
Clock (f
OSC
/2 – >
50ns)
Required Start/
Stop Hold Time
Note
00h 1EA 50ns
When Bit 7 (enable bit) = 0, the number of
sample clock is 1EA (ignore Bit 6 to Bit 0)
80h 1EA 50ns
81h 2EA 100ns
82h 3EA 150ns
... ... ...
8Bh 12EA 600ns Fast Mode I²C Start/Stop hold time specification
... ... ...
FFh 128EA 6000ns
System Clock
S1SETUP,
S2SETUP Register
Value
Number of Sample
Clock
Required Start/Stop Hold Time
40MHz (f
OSC
/2 – > 50ns)
8Bh 12 EA 600ns
30MHz (f
OSC
/2 – > 66.6ns)
89h 9 EA 600ns
20MHz (f
OSC
/2 – > 100ns)
86h 6 EA 600ns
8MHz (f
OSC
/2 – > 250ns)
83h 3 EA 750ns