NXP Semiconductors LPCXpresso804 User Manual

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 16NXP Semiconductors LPCXpresso804User ManualA digital oscillator circuit is also included on the Shield, with 1.024kHz and 8Hz outputsavailable. LPC804 signal PIO0_1 can be connected to these oscillator signals in order toprovide a low speed clock to the flip-flops in the PLU block. The center pin (2) of JP12connects to PIO0_1, so a jumper can be placed onto JP12 to connect this signal to therequired clock (see markings on the Shield silk screen.) An external clock can be providedto the PLU by connecting it to the center pin of JP12.8.2 PLU output optionsAll 8 possible PLU output ports may be connected to LEDs via jumpers to give an easymethod for simple visualization or to allow connection to those outputs. Table 8 showsthese connections. Note that some connections are shared so require otherconfigurations/settings before use (see Notes column in the table.)8.3 DAC/ADC continuity tester circuitThe PLU shield includes a simple circuit to implement a continuity tester, as shown below.Table 7. PLU input on/off switchesSwitch LPC804 signal NotesS1 PIO0_0 Also connected to debug UART. Remove JP2 to avoid conflictsS2 PIO0_10 Shared with potentiometer. Move potentiometer to center position toavoid conflicts.S3 PIO0_11 Also connected to user LED; remove JP21 to disconnect LEDS4 PIO0_4 Also connected to debug UART. Remove JP24 to avoid conflictsS5 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 LEDsLED LPC804signalJumper installedto enableNotesD1 PIO0_15 JP6D2 PIO0_16 JP7D3 PIO0_10 JP8 Ensure S2 is in VCC position to use.D4 PIO0_18 JP9D5 PIO0_12 JP10 Also used for green User LED. Remove JP22 toisolate.D6 PIO0_20 JP11D7 PIO0_7 JP4 I 2C connections also used for LM75. Remove JP23to isolate.D8 PIO0_14 JP5 I 2C connections also used for LM75. Remove JP23to isolate.