LS_I2C controller
RM0082
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Doc ID 018672 Rev 1
28.6.10 IC_FS_SCL_HCNT register(0x01C)
The IC_FS_SCL_HCNT is a 16 bit RW register which allows to set the high period of the
SCL clock for fast-speed mode. The IC_FS_SCL_HCNT bit assignments are given in
Note:
1
This register can be written only when the I
2
C controller is disabled, which corresponds to
the IC_ENABLE (
) register being set to ‘b0. Write at other times has no
effect.
2
This register must be set before any I
2
C bus transaction can take place in order to ensure
proper I/O timing.
100
125
4.7
16‘h024C/’d588
4.70
100
1000
4.7
16‘h125C/’d4700
4.70
Table 550.
IC_SS_SCL_LCNT sample calculations (continued)
I
2
C data rate - SS
(Kbps)
SCL clock
frequency
(MHz)
SCL low time
required min
(µs)
IC_SS_SCL_LCNT
(hex/decimal)
SCL low
timeactual
(µs)
Table 551.
IC_FS_SCL_HCNT register bit assignments
Bit
Name
Type
Reset
value
Description
[15:00]
IC_FS_SCL_HCNT
RW
16'h64
SCL clock high period count for fast speed.
This 16 bit field states the SCL clock high period
count for fast speed. The minimum valid value is
6, and hardware prevents that a value less than
this minimum will be written (setting 6 if
attempted). It is used in high speed mode to
send the master code and START BYTE or
general CALL.
Table 552.
IC_FS_SCL_HCNT sample calculations
I
2
C data rate - FS
(Kbps)
SCL clock
frequency
(MHz)
SCL high time
required min
(µs)
IC_FS_SCL_HCNT
(hex/decimal)
SCL high time
actual
(µs)
400
10
0.6
16‘h0006/’d6
0.60
400
25
0.6
16‘h000F/’d15
0.60
400
50
0.6
16‘h001E/’d30
0.60
400
75
0.6
16‘h002D/’d45
0.60
400
100
0.6
16‘h003C/’d60
0.60
400
125
0.6
16‘h004B/’d75
0.60
400
1000
0.6
16‘h0258/’d600
0.60