LPC1837FET256,551 NXP Semiconductors, LPC1837FET256,551 Datasheet - Page 399

• Manufacturer Part Number: LPC1837FET256,551
• Description: Microcontrollers (MCU) 32BIT ARM CORTEX-M3 MCU 136KB SRAM
• Manufacturer: NXP Semiconductors
• Series: LPC18xxr

Specifications of LPC1837FET256,551

• Core: ARM Cortex M3
• Core Processor: ARM® Cortex-M3™
• Core Size: 32-Bit
• Speed: 150MHz
• Connectivity: CAN, EBI/EMI, Ethernet, I²C, Microwire, SD/MMC, SPI, SSI, SSP, UART/USART, USB OTG
• Peripherals: Brown-out Detect/Reset, DMA, I²S, Motor Control PWM, POR, PWM, WDT
• Number Of I /o: 80
• Program Memory Size: 1MB (1M x 8)
• Program Memory Type: FLASH
• Eeprom Size: -
• Ram Size: 136K x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 3.6 V
• Data Converters: A/D 16x10b; D/A 1x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 256-LBGA
• Lead Free Status / Rohs Status: Details
• Other names: 935293795551

NXP Semiconductors
<Document ID>
User manual
20.7.8.1 Auto reset
20.7.8.2 Data pulse
20.7.8.3 B-disconnect to A-connect (Transition to the A-peripheral state)
When the HAAR in the OTGSC register is set to one, the host will automatically start a
reset after a connect event. This shortcuts the normal process where software is notified
of the connect event and starts the reset. Software will still receive notification of the
connect event (CCS bit in the PORTSC register) but should not write the reset bit in the
USBCMD register when the HAAR is set. Software will be notified again after the reset is
complete via the enable change bit in the PORTSC register which causes a port change
interrupt.
This assist will ensure the OTG parameter TB_ACON_BSE0_MAX = 1 ms is met (see
OTG specification for an explanation of the OTG timing requirements).
Writing a one to HADP in the OTGSC register will start a data pulse of approximately 7 ms
in duration and then automatically cease the data pulsing. During the data pulse, the DP
bit will be set and then cleared. This automation relieves software from accurately
controlling the data-pulse duration. During the data pulse, the HCD can poll to see that the
HADP and DP bit have returned low to recognize the completion, or the HCD can simply
launch the data pulse and wait to see if a VBUS Valid interrupt occurs when the A-side
supplies bus power.
This assist will ensure data pulsing meets the OTG requirement of > 5 ms and < 10 ms.
During HNP, the B-disconnect occurs from the OTG A_suspend state, and within 3 ms,
the A-device must enable the pull-up on the DP leg in the A-peripheral state. For the
hardware assist to begin the following conditions must be met:
The hardware assist consists of the following steps:
When software has enabled this hardware assist, it must not interfere during the transition
and should not write any register in the OTG core until it gets an interrupt from the device
controller signifying that a reset interrupt has occurred or until it has verified that the core
has entered device mode. HCD/DCD must not activate the core soft reset at any time
1. Hardware resets the OTG controller (writes 1 to the RST bit in USBCMD).
2. Hardware selects the device mode (writes 10 to bits CM[1:0] in USBMODE).
3. Hardware sets the RS bit in USBCMD and enables the necessary interrupts:
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Auto reset (set bit HAAR).
Data pulse (set bit HADP).
B-disconnect to A-connect (set bit HABA).
HABA is set.
Host controller is in suspend mode.
Device is disconnecting.
– USB reset enable (URE) - enables interrupt on USB bus reset to device.
– Sleep enable (SLE) - enables interrupt on device suspend.
– Port change detect enable (PCE) - enables interrupt on device connect.
All information provided in this document is subject to legal disclaimers.
Rev. 00.13 — 20 July 2011
Chapter 20: LPC18xx USB0 Host/Device/OTG controller
UM10430
© NXP B.V. 2011. All rights reserved.
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