Enhanced Modular Input/Output Subsystem (eMIOS200)
23-28
Freescale Semiconductor
PXR40 Microcontroller Reference Manual, Rev. 1
EMIOS_CBDR[
n
] register. Reading EMIOS_CBDR[
n
] register forces A1 content to be transferred to B1
and re-enables transfers from B2 to B1, to take effect at the next edge capture.
The input pulse period is calculated by subtracting the value in B1 from A2.
shows how the unified channel can be used for input period measurement.
Figure 23-20. IPM Example
shows the A1 and B1 register updates when EMIOS_CADR[
n
] and EMIOS_CBDR[
n
] read
operations are performed. When a EMIOS_CADR[
n
] read occurs, the contents of A1 are transferred to
B1, thus providing coherent data in the A2 and B1 registers. Transfers from B2 to B1 are then blocked until
EMIOS_CBDR[
n
] is read. After EMIOS_CBDR[
n
] is read, the contents of register A1 are transferred to
register B1 and the transfers from B2 to B1 are re-enabled to occur at the transfer edges, which is the
leading edge in the
example.
Figure 23-21. A1 and B1 Updates at EMIOS_CADR[n] and EMIOS_CBDR[n] Reads
selected counter bus
0x000500
0x001000
0x001100
0x001250
0x001525
0x0016A0
A2(captured) value
2
A1 value
B2 (captured) value
$0xxxxxxx
0x001000
0x001250
$0xxxxxxx
0x001000
0x001250
0x0016A0
$0xxxxxxx
0x001000
0x001250
0x0016A0
Input signal
1
EDPOL = 1
FLAG pin register
Notes: 1. After input filter
2. EMIOSA[n] = A2
3. EMIOSB[n] = B1
A
A
A
B1 value
3
$0xxxxxxx
0x001000
0x001250
0x000500
0x001000
0x001100
0x001250
0x001525
0x0016A0
Selected
Counter Bus
FLAG Set Event
A
A
A
A2 (Captured) Value
2
0xxxxxxx
Notes:
1. After input filter
2. EMIOS_CADR[n] = A2
Input Signal
1
EDPOL = 1
B1 Value
3
0x001525
0xxxxxxx
0xxxxxxx
0x001000
0x001250
0x0016A0
B2 (Captured) Value
3. EMIOS_CBDR[n] = B1
0xxxxxxx
0x001250
A1 Value
0x001000
Read EMIOS_CADR[n]
Read EMIOS_CBDR[n]
0x001100
0x001250
0x001000
0x001000
0x001250
Summary of Contents for PXR4030
Page 1: ...PXR40 Microcontroller Reference Manual Devices Supported PXR4030 PXR4040 PXR40RM Rev 1 06 2011...
Page 30: ...PXR40 Microcontroller Reference Manual Rev 1 Freescale Semiconductor xxx...
Page 40: ...PXR40 Microcontroller Reference Manual Rev 1 xl Freescale Semiconductor...
Page 66: ...Memory Map PXR40 Microcontroller Reference Manual Rev 1 2 4 Freescale Semiconductor...
Page 120: ...Signal Descriptions 3 54 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Page 860: ...FlexCAN Module 24 50 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Page 1167: ...Decimation Filter Freescale Semiconductor 28 53 PXR40 Microcontroller Reference Manual Rev 1...
Page 1168: ...Decimation Filter 28 54 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...