SPRUJD3A July 2025 – October 2025 F28E120SB , F28E120SC
On this device, the Input X-BAR is used to route signals from a GPIO to many different IP blocks such as the ADC, eCAP, MCPWM, and external interrupts. The input of each Input X-BAR instance (INPUTx) can be any GPIO , while the output of each instance connects to various IP blocks in the device. The digital input of AIOs are also available as inputs to the Input X-BAR. This flexibility relieves some of the constraints on peripheral muxing by allowing the user to connect any GPIO to the specified outputs of each Input X-BAR instance. Note that the GPIO selected by the Input X-BAR can be configured as either an input or an output. The Input X-BAR simply connects the signal on the input buffer to the output of the selected Input X-BAR instance. Therefore, you can do things such as route the output of an MCPWM to the eCAP module for a frequency test).
The Input X-BAR is configured by way of the INPUTxSELECT registers. The destinations for each INPUTx are shown in Figure 9-1 and Table 9-1. For additional details on how each Input X-BAR connects to other IP blocks throughout the device, look for references to Input X-BAR in the chapter associated with that IP. Note that the destinations of each INPUTx are fixed and are not user-configurable. For more information on configuring the Input X-BAR, see the INPUT_XBAR_REGS register definitions in the XBAR Registers section.
Figure 9-1 Input X-BAR| INPUT | ECAP | PWM XBAR | OUTPUT XBAR | CPU XINT | ADC START OF CONVERSION | PWM / ECAP SYNC | DCCx | CMPSS |
|---|---|---|---|---|---|---|---|---|
| 1 | Yes | Yes | Yes | - | - | - | - | - |
| 2 | Yes | Yes | Yes | - | - | - | - | - |
| 3 | Yes | Yes | Yes | - | - | - | - | - |
| 4 | Yes | Yes | Yes | XINT1 | - | - | - | - |
| 5 | Yes | Yes | Yes | XINT2 | ADCEXTSOC | EXTSYNCIN1 | - | - |
| 6 | Yes | Yes | Yes | XINT3 | - | EXTSYNCIN2 | - | - |
| 7 | Yes | Yes | - | - | - | - | - | CMPSS1_EXT_FILTIN_H[1] / CMPSS3_EXT_FILTIN_H[1] |
| 8 | Yes | Yes | - | - | - | - | - | CMPSS1_EXT_FILTIN_L[1] / CMPSS3_EXT_FILTIN_L[1] |
| 9 | Yes | Yes | - | - | - | - | - | CMPSS2_EXT_FILTIN_H[1] / CMPSS4_EXT_FILTIN_H[1] |
| 10 | Yes | Yes | - | - | - | - | - | CMPSS2_EXT_FILTIN_L[1] / CMPSS4_EXT_FILTIN_L[1] |
| 11 | Yes | Yes | - | - | - | - | CLK1 | - |
| 12 | Yes | Yes | - | - | - | - | CLK1 | - |
| 13 | Yes | Yes | - | XINT4 | - | - | - | - |
| 14 | Yes | Yes | - | XINT5 | - | - | - | - |
| 15 | Yes | - | - | - | - | - | CLK1 | - |
| 16 | Yes | - | - | - | - | - | CLK0 | - |