Jon Wilder
Active Member
So the PIC18F27Q84 has 4 dedicated PWM modules (PWM1 - PWM4). In the datasheet where it talks about the output slices, it says -
The part where it says "An output slice consists of two PWM outputs, PWMxSaP1_out and PWMx_SaP2_out"...the names of the outputs would be say PWM1S1P1 and PWM1S1P2, which I take to mean PWM Module 1 Slice 1 Parameter 1 and PWM1 Slice 1 Parameter 2 (the parameter registers are two 8-bit cascaded 16-bit registers for the duty cycle value). This would be one slice. As a PWM module can have up to four output slices, I would think each PWM module would have 3 additional slices named PWM1S2P1/PWM1S2P2, PWM1S3P1/PWM1S3P2, and PWM1S4P1/PWM1S4P2. However, each of the 4 PWM modules only has one slice, denoted by the 'S1P1/S1P2 outputs on each of the 4 PWM modules. There is no S2/S3/S4 register for any of the PWM modules.
As it does have a mirror bit for the hardware enable control bit as well as the duty cycle load bit, which can control the EN and LD bits of all 4 PWM modules simultaneously, all I can see is that you can configure and combine each of the 4 PWM modules as one, with two output slices each, to work as one combined PWM module with a total of 4 two output slices.
But the wording in the datasheet does not imply this at all. As a matter of fact, even having the 'S1' in the parameter register name and no other 'S' values implies that in fact, each PWM module only has ONE output slice.
Can someone more experienced than I maybe shed some light on this?
The part where it says "An output slice consists of two PWM outputs, PWMxSaP1_out and PWMx_SaP2_out"...the names of the outputs would be say PWM1S1P1 and PWM1S1P2, which I take to mean PWM Module 1 Slice 1 Parameter 1 and PWM1 Slice 1 Parameter 2 (the parameter registers are two 8-bit cascaded 16-bit registers for the duty cycle value). This would be one slice. As a PWM module can have up to four output slices, I would think each PWM module would have 3 additional slices named PWM1S2P1/PWM1S2P2, PWM1S3P1/PWM1S3P2, and PWM1S4P1/PWM1S4P2. However, each of the 4 PWM modules only has one slice, denoted by the 'S1P1/S1P2 outputs on each of the 4 PWM modules. There is no S2/S3/S4 register for any of the PWM modules.
As it does have a mirror bit for the hardware enable control bit as well as the duty cycle load bit, which can control the EN and LD bits of all 4 PWM modules simultaneously, all I can see is that you can configure and combine each of the 4 PWM modules as one, with two output slices each, to work as one combined PWM module with a total of 4 two output slices.
But the wording in the datasheet does not imply this at all. As a matter of fact, even having the 'S1' in the parameter register name and no other 'S' values implies that in fact, each PWM module only has ONE output slice.
Can someone more experienced than I maybe shed some light on this?
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