NXP Semiconductors LPCXpresso804, Руководство пользователя

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UM11083 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2018. All rights reserved.
User Manual Rev. 1.1 — 24 September 2018 12 of 16
NXP Semiconductors
LPCXpresso804
User Manual
A digital oscillator circuit is also included on the Shield, with 1.024kHz and 8Hz outputs
available. LPC804 signal PIO0_1 can be connected to these oscillator signals in order to
provide a low speed clock to the flip-flops in the PLU block. The center pin (2) of JP12
connects to PIO0_1, so a jumper can be placed onto JP12 to connect this signal to the
required clock (see markings on the Shield silk screen.) An external clock can be provided
to the PLU by connecting it to the center pin of JP12.
8.2 PLU output options
All 8 possible PLU output ports may be connected to LEDs via jumpers to give an easy
method for simple visualization or to allow connection to those outputs.
Table 8 shows
these connections. Note that some connections are shared so require other
configurations/settings before use (see Notes column in the table.)
8.3 DAC/ADC continuity tester circuit
The PLU shield includes a simple circuit to implement a continuity tester, as shown below.
Table 7. PLU input on/off switches
Switch LPC804 signal Notes
S1 PIO0_0 Also connected to debug UART. Remove JP2 to avoid conflicts
S2 PIO0_10 Shared with potentiometer. Move potentiometer to center position to
avoid conflicts.
S3 PIO0_11 Also connected to user LED; remove JP21 to disconnect LED
S4 PIO0_4 Also connected to debug UART. Remove JP24 to avoid conflicts
S5 PIO0_13 Also connected to user LED; remove JP25 to disconnect LED.
S6 PIO0_8 Also connected to SPI flash data input.
Table 8. PLU shield LEDs
LED LPC804
signal Jumper installed
to enable Notes
D1 PIO0_15 JP6
D2 PIO0_16 JP7
D3 PIO0_10 JP8 Ensure S2 is in VCC position to use.
D4 PIO0_18 JP9
D5 PIO0_12 JP10 Also used for green User LED. Remove JP22 to
isolate.
D6 PIO0_20 JP11
D7 PIO0_7 JP4 I
2
C connections also used for LM75. Remove JP23
to isolate.
D8 PIO0_14 JP5 I
2
C connections also used for LM75. Remove JP23
to isolate.