FT4232HQ - REEL FTDI, Future Technology Devices International Ltd, FT4232HQ - REEL Datasheet - Page 21

• Manufacturer Part Number: FT4232HQ - REEL
• Description: IC USB UART/MPSSE QUAD HS 64-QFN
• Manufacturer: FTDI, Future Technology Devices International Ltd
• Series: USBmadeEZ-FIFOr

Specifications of FT4232HQ - REEL

• Features: USB to UART and/or SPI, I2C, JTAG
• Number Of Channels: 4, QUART
• Fifo's: 2048 Byte
• Protocol: RS-232, RS-422, RS-485
• Voltage - Supply: 3 V ~ 3.6 V
• With Auto Flow Control: Yes
• With Modem Control: Yes
• With Cmos: Yes
• Mounting Type: Surface Mount
• Package / Case: 64-QFN
• For Use With: 768-1031 - MOD USB HS FT4232H EVAL
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 768-1027-2; FT4232HQ - REEL

4.4.1 MPSSE Adaptive Clocking
Adaptive clocking is a new MPSSE feature added to the FT24232H MPSSE engine.
The mode is effectively handshaking the CLK signal with a return clock RTCK. This is a technique used by
ARM processors.
The FT4232H will assert the CLK line and wait for the RTCK to be returned from the target device to
GPIOL3 line before changing the TDO (data out line).
Figure 4.5 Adaptive Clocking Interconnect
Figure 4.6: Adaptive Clocking waveform.
Adaptive clocking is not enabled by default.
See: AN_108 Command Processor for MPSSE and MCU Host Bus Emulation Modes.
RTCK
TDO
TCK
FT4232H
GPIOL3
TDO
TCK
Copyright © 2010 Future Technology Devices International Limited
FT4232H QUAD HIGH SPEED USB TO MULTIPURPOSE UART/MPSSE IC
RTCK
ARM CPU
TDO changes on falling
edge of TCK
Document No.: FT_000060
Clearance No.: FTDI#78
Datasheet Version 2.10
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