SDA_HD=B_0x0
I3C timing register 1
| AVAL | number of kernel clock cycles, that is used whatever I3C is acting as controller or target, to set the following MIPI I3C timings, like bus available condition time: When the I3C is acting as target: for bus available condition time: it must wait for (bus available condition) time to be elapsed after a stop and before issuing a start request for an IBI or a controller-role request (i.e. bus free condition is sustained for at least tAVAL). refer to MIPI timing tAVAL = 1 s. This timing is defined by: tAVAL = (AVAL[7:0] + 2) x tI3CCLK for bus idle condition time: it must wait for (bus idle condition) time to be elapsed after that both SDA and SCL are continuously high and stable before issuing a hot-join event. Refer to MIPI v1.1 timing tIDLE = 200 s . This timing is defined by: tIDLE = (AVAL[7:0] + 2) x 200 x tI3CCLK When the I3C is acting as controller, it can not stall the clock beyond a maximum stall time (i.e. stall the SCL clock low), as follows: on first bit of assigned address during dynamic address assignment: it can not stall the clock beyond the MIPI timing tSTALLDAA = 15 ms. This timing is defined by: tSTALLDAA = (AVAL[7:0] + 1) x 15000 x tI3CCLK on ACK/NACK phase of I3C/I2C transfer, on parity bit of write data transfer, on transition bit of I3C read transfer: it can not stall the clock beyond the MIPI timing tSTALL = 100 s. This timing is defined by: tSTALL = (AVAL[7:0] + 1) x 100 x tI3CCLK Whatever the I3C is acting as controller or as (controller-capable) target, during a controller-role hand-off procedure: The new controller must wait for a time (refer to MIPI timing tNEWCRLock) before pulling SDA low (i.e. issuing a start). And the active controller must wait for the same time while monitoring new controller and before testing the new controller by pulling SDA low. This time to wait is dependent on the defined I3C_TIMINGR1.ANSCR[1:0], as follows: If ASNCR[1:0]=00: tNEWCRLock = (AVAL[7:0] + 1) x tI3CCLK If ASNCR[1:0]=01: tNEWCRLock = (AVAL[7:0] + 1) x 100 x tI3CCLK If ASNCR[1:0]=10: tNEWCRLock = (AVAL[7:0] + 1) x 2000 x tI3CCLK If ASNCR[1:0]=11: tNEWCRLock = (AVAL[7:0] + 1) x 50000 x tI3CCLK |
| ASNCR | activity state of the new controller (when I3C is acting asactive- controller) This field indicates the time to wait before being accessed as new target, refer to the other field AVAL[7:0]. This field can be modified only when the I3C is acting as controller. |
| FREE | number of kernel clocks cycles that is used to set some MIPI timings like bus free condition time (when the I3C is acting as controller) When the I3C is acting as controller: for I3C start timing: it must wait for (bus free condition) time to be elapsed after a stop and before a start, refer to MIPI timings (I3C) tCAS and (I2C) tBUF. These timings are defined by: tBUF= tCAS = [ (FREE[6:0] + 1) x 2(0,5 + SDA_HD)] x tI3CCLK Note: for pure I3C bus: tCASmin= 38,4 ns. Note: for pure I3C bus: tCASmax=1s, 100s, 2ms, 50ms for respectively ENTAS0,1,2, and 3. Note: for mixed bus with I2C fm+ device: tBUFmin = 0,5 s. Note: for mixed bus with I2C fm device: tBUFmin = 1,3 s. for I3C repeated start timing: it must wait for time to be elapsed after a repeated start (i.e. SDA is de-asserted) and before driving SCL low, refer to. MIPI timing tCASr. This timing is defined by: tCASr = [ (FREE[6:0] + 1) x 2(0,5 + SDA_HD)] x tI3CCLK for I3C stop timing: it must wait for time to be elapsed after that the SCL clock is driven high and before the stop condition (i.e. SDA is asserted). This timing is defined by: tCBP = (FREE[6:0] + 1) x tI3CCLK for I3C repeated start timing (T-bit when controller ends read with repeated start followed by stop): it must wait for time to be elapsed after that the SCL clock is driven high and before the repeated start condition (i.e. SDA is de-asserted). This timing is defined by: tCBSr = (FREE[6:0] + 1) x tI3CCLK |
| SDA_HD | SDA hold time (when the I3C is acting as controller), in number of kernel clocks cycles (refer to MIPI timing SDA hold time in push-pull tHD_PP): 0 (B_0x0): SDA hold time = 0,5 x tI3CCLK 1 (B_0x1): SDA hold time = 1,5 x tI3CCLK |