Datasheet

Table Of Contents
Table 485.
IC_SS_SCL_HCNT
Register
Bits Name Description Type Reset
31:16 Reserved. - - -
15:0 IC_SS_SCL_HCNT This register must be set before any I2C bus transaction
can take place to ensure proper I/O timing. This register
sets the SCL clock high-period count for standard speed.
For more information, refer to 'IC_CLK Frequency
Configuration'.
This register can be written only when the I2C interface is
disabled which corresponds to the IC_ENABLE[0] register
being set to 0. Writes at other times have no effect.
The minimum valid value is 6; hardware prevents values
less than this being written, and if attempted results in 6
being set. For designs with APB_DATA_WIDTH = 8, the
order of programming is important to ensure the correct
operation of the DW_apb_i2c. The lower byte must be
programmed first. Then the upper byte is programmed.
NOTE: This register must not be programmed to a value
higher than 65525, because DW_apb_i2c uses a 16-bit
counter to flag an I2C bus idle condition when this counter
reaches a value of IC_SS_SCL_HCNT + 10.
RW 0x0028
IC_SS_SCL_LCNT Register
Description
Standard Speed I2C Clock SCL Low Count Register
Table 486.
IC_SS_SCL_LCNT
Register
Bits Name Description Type Reset
31:16 Reserved. - - -
15:0 IC_SS_SCL_LCNT This register must be set before any I2C bus transaction
can take place to ensure proper I/O timing. This register
sets the SCL clock low period count for standard speed.
For more information, refer to 'IC_CLK Frequency
Configuration'
This register can be written only when the I2C interface is
disabled which corresponds to the IC_ENABLE[0] register
being set to 0. Writes at other times have no effect.
The minimum valid value is 8; hardware prevents values
less than this being written, and if attempted, results in 8
being set. For designs with APB_DATA_WIDTH = 8, the
order of programming is important to ensure the correct
operation of DW_apb_i2c. The lower byte must be
programmed first, and then the upper byte is programmed.
RW 0x002f
IC_FS_SCL_HCNT Register
Description
Fast Mode or Fast Mode Plus I2C Clock SCL High Count Register
RP2040 Datasheet
4.4. I2C 496