Migrating PDIUSBD12 to FT120

Application Note
AN_209
AN_209 PDIUSBD12 to FT120
Migration Guide
Version 1.1
Issue Date: 2012-12-14
The FT120 is a cost and feature optimized USB Full-Speed device controller. It
communicates with a micro-controller over a generic parallel interface, and
integrates USB device/slave functionality into a system. This application note
describes how to implement the device in legacy designs where the
PDIUSBD12 was being used, as well as some minor differences between the
two chips.
Use of FTDI devices in life support and/or safety applications is entirely at the user’s risk, and the
user agrees to defend, indemnify and hold FTDI harmless from any and all damages, claims, suits
or expense resulting from such use.
Future Technology Devices International Limited (FTDI)
Unit 1, 2 Seaward Place, Glasgow G41 1HH, United Kingdom
Tel.: +44 (0) 141 429 2777 Fax: + 44 (0) 141 429 2758
Web Site: http://ftdichip.com
Copyright © 2012 Future Technology Devices International Limited
Application Note
AN_209 PDIUSBD12 to FT120 Migration Guide
Version 1.1
Document Reference No.: FT_000676
Clearance No.: FTDI# 289
Table of Contents
1
Introduction .................................................................................................................................... 2
2
FT120 vs PDIUSBD12 ....................................................................................................................... 3
2.1
Features .................................................................................................................................. 3
2.2
Pinout ...................................................................................................................................... 4
3
Reference Schematic ...................................................................................................................... 6
4
BOM Changes Required .................................................................................................................. 7
5
Firmware ......................................................................................................................................... 8
5.1
Set DMA Functional Difference............................................................................................... 9
5.2
CLKOUT and SUSPEND Pin Differences ................................................................................. 10
6
IO Levels ........................................................................................................................................ 11
7
Ordering Information. ................................................................................................................... 12
8
Summary ....................................................................................................................................... 13
9
Contact Information...................................................................................................................... 14
Appendix A – References ...................................................................................................................... 15
Document References....................................................................................................................... 15
Acronyms and Abbreviations ............................................................................................................ 15
Appendix B – List of Tables & Figures ................................................................................................... 16
List of Tables ..................................................................................................................................... 16
List of Figures .................................................................................................................................... 16
Appendix C – Revision History .............................................................................................................. 17
1
Copyright © 2012 Future Technology Devices International Limited
Application Note
AN_209 PDIUSBD12 to FT120 Migration Guide
Version 1.1
Document Reference No.: FT_000676
Clearance No.: FTDI# 289
1 Introduction
The FT120 is a cost and feature optimized USB full-speed device controller. It communicates with
a micro-controller over the generic parallel interface. The design closely matches the PDIUSBD12
which has been a very popular USB solution over the past decade, but is now becoming
increasingly difficult to source in volume. To fill this gap in the market, the FT120T (28 pin TSSOP
package) may be used in designs originally intended for PDIUSBD12 devices by following the
advice in this application note.
2
Copyright © 2012 Future Technology Devices International Limited
Application Note
AN_209 PDIUSBD12 to FT120 Migration Guide
Version 1.1
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Clearance No.: FTDI# 289
2 FT120 vs PDIUSBD12
2.1 Features
The main features of the two generations of devices are shown below. To maximize compatibility,
the 28 pin TSSOP package has been selected.
FEATURE
FT120
PDIUSBD12
28 pin TSSOP
28 pin TSSOP
28 Pin QFN
SO28
-40°C to 85°C
-40°C to 85°C
VCC Supply
3V3 or 5.0V
3V3 or 5.0V
IO Levels
3V3 (5V tolerant)
3V3 or 5.0V
Operating Current
7mA
15mA
Suspend current
83uA
15uA
Speed
Full Speed
Full Speed
Transfer Modes
Bulk / Isochronous / Interrupt
Bulk / Isochronous / Interrupt
MECHANICAL
Packages
Temperature
ELECTRICAL
USB Modes
DATA THROUGHPUT
Bulk mode
Isochronous mode
DMA ENGINE
Up to 1MByte/s (typical)
Up to 1Mbit/s (typical)
YES
Up to 1MByte/s (typical)
Up to 1Mbit/s (typical)
YES
Table 2.1 Feature comparison
3
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Application Note
AN_209 PDIUSBD12 to FT120 Migration Guide
Version 1.1
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2.2 Pinout
The pinout of the two devices match as per the table below:
PIN
FT120T
PDIUSBD12
DESCRIPTION
1
DATA0
DATA0
Bit 0 of bi-directional data.
2
DATA1
DATA1
Bit 1 of bi-directional data.
3
DATA2
DATA2
Bit 2 of bi-directional data.
4
DATA3
DATA3
Bit 3 of bi-directional data.
5
GND
GND
Ground
6
DATA4
DATA4
Bit 4 of bi-directional data.
7
DATA5
DATA5
Bit 5 of bi-directional data.
8
DATA6
DATA6
Bit 6 of bi-directional data.
9
DATA7
DATA7
Bit 7 of bi-directional data.
ALE
Address Latch Enable. The falling edge
is used to close the latch of the address
information in a multiplexed address/
data bus. Permanently tied low for
separate address/ data bus
configuration.
CS_N
Chip Select (Active Low)
SUSPEND
Device suspend(output) and
wakeup(input)
10
11
12
ALE
CS_N
SUSPEND
13
CLKOUT
CLKOUT
Programmable Output Clock
14
INT_N
INT_N
Interrupt (Active Low)
15
RD_N
RD_N
Read Strobe (Active Low)
16
WR_N
WR_N
Write Strobe (Active Low)
17
DMREQ
DMREQ
DMA Request.
18
DMACK_N
DMACK_N
DMA Acknowledge (Active Low).
EOT_N
End of DMA Transfer (Active Low).
Double up as Vbus sensing. EOT_N is
only valid when asserted together with
DMACK_N and either RD_N or WR_N.
RESET_N
Reset (Active Low and asynchronous).
Built-in power-on reset circuit is present onchip, so this pin can be tied to VCC.
19
20
EOT_N
RESET_N
4
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Application Note
AN_209 PDIUSBD12 to FT120 Migration Guide
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PIN
FT120T
PDIUSBD12
DESCRIPTION
21
GL_N
GL_N
USB traffic LED indicator (Active Low)
XTAL1
Crystal connection 1 (6MHz);
alternatively, a 1.8V square wave clock
can be applied.
XTAL1
22
23
XTAL2
XTAL2
Crystal connection 2 (6MHz) ; if the
external clock signal, instead of
the crystal, is connected to XTAL1, then
XTAL2 should be left unconnected
Voltage supply (4.0 - 5.5V); To operate
the IC at 3.3 V, supply 3.3 V to both the
VCC and 3V3OUT pins
24
Vcc
Vcc
25
USBDM
D-
USB D- data line
26
USBDP
D+
USB D+ data line
VOUT3.3
3.3V regulated output; To operate the
IC at 3.3 V, supply 3.3 V to both the
VCC and 3V3OUT pins
3V3OUT
27
Address bit.
A0=1 selects command instruction;
28
A0
A0
A0=0 selects the data phase.
This pin is ignored in the multiplexed
address and data bus configuration and
should be tied to HIGH.
Table 2.2 Pinout comparison
5
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Application Note
AN_209 PDIUSBD12 to FT120 Migration Guide
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Document Reference No.: FT_000676
Clearance No.: FTDI# 289
3 Reference Schematic
Figure 3.1 shows a reference schematic. All power and termination options are the same as per a
PDIUSBD12 schematic.
Figure 3.1 Reference Schematic
6
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AN_209 PDIUSBD12 to FT120 Migration Guide
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4 BOM Changes Required
The only BOM change required to a design already using a PDIUSBD12 28 pin TSSOP device is to
replace the device with the FT120.
7
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AN_209 PDIUSBD12 to FT120 Migration Guide
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5 Firmware
The register map for the PDIUSBD12 and the FT120 are the same. This allows the control firmware
used for the PDIUSBD12 to be compatible with the FT120 and therefore application software
should not need to be changed. FTDI recommends that application software be revalidated with
the new chip.
Command Name
Recipient
Coding
Data phase
Initialization Commands
Set Address / Enable
Device
D0h
Write 1 byte
Set Endpoint Enable
Device
D8h
Write 1 byte
Set Mode
Device
F3h
Write 2 byte
Set DMA
Device
FBh
Write/Read 1 byte
Data Flow Commands
Read Interrupt Register
Device
F4h
Read 2 bytes
Select Endpoint
Control OUT
00h
Read 1 byte (optional)
Control IN
01h
Read 1 byte (optional)
Endpoint 1 OUT
02h
Read 1 byte (optional)
Endpoint 1 IN
03h
Read 1 byte (optional)
Endpoint 2 OUT
04h
Read 1 byte (optional)
Endpoint 2 IN
05h
Read 1 byte (optional)
Control OUT
40h
Read 1 byte
Control IN
41h
Read 1 byte
Endpoint 1 OUT
42h
Read 1 byte
Endpoint 1 IN
43h
Read 1 byte
Endpoint 2 OUT
44h
Read 1 byte
Endpoint 2 IN
45h
Read 1 byte
Control OUT
80h
Read 1 byte
Control IN
81h
Read 1 byte
Endpoint 1 OUT
82h
Read 1 byte
Endpoint 1 IN
83h
Read 1 byte
Endpoint 2 OUT
84h
Read 1 byte
Read Last Transaction
Status
Read Endpoint Status
8
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Application Note
AN_209 PDIUSBD12 to FT120 Migration Guide
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Endpoint 2 IN
85h
Read 1 byte
Read Buffer
Selected Endpoint
F0h
Read n bytes
Write Buffer
Selected Endpoint
F0h
Write n bytes
Set Endpoint Status
Control OUT
40h
Write 1 byte
Control IN
41h
Write 1 byte
Endpoint 1 OUT
42h
Write 1 byte
Endpoint 1 IN
43h
Write 1 byte
Endpoint 2 OUT
44h
Write 1 byte
Endpoint 2 IN
45h
Write 1 byte
Acknowledge Setup
Selected Endpoint
F1h
None
Clear Buffer
Selected Endpoint
F2h
None
Validate Buffer
Selected Endpoint
FAh
None
F6h
None
F5h
Read 1 or 2 bytes
General Commands
Send Resume
Read
Current
Frame
Number
Table 5.1 Register list
The bit mapping for each register is available in the FT120 datasheet.
5.1 Set DMA Functional Difference
In register FB (Set DMA) bits 6 and 7 allow for interrupts to be enabled / disabled.
With the PDIUSBD12, interrupts will be generated regardless of the setting in this register.
With the FT120, the interrupt will be enabled/disabled according to the value set when used in
DMA mode.
To ensure maximum compatibility with PDIUSBD12 designs it is recommended the interrupts are
enabled in this register. However new designs may use these bits to set the interrupts as per the
design requirements.
Firmware using non-DMA mode is not affected.
9
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Application Note
AN_209 PDIUSBD12 to FT120 Migration Guide
Version 1.1
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Clearance No.: FTDI# 289
5.2 CLKOUT and SUSPEND Pin Differences
The FT120 has a variety of different clock modes configured with the Set Mode register F3 as
shown in Table 5.2 affecting the CLKOUT and SUSPEND pin.
Table 5.2 Clock Modes
Modes 0 and 3 are 100% backward compatible with the PDIUSBD12, but for designs originally
using mode 1, (NO LAZY CLOCK = 0 and CLOCK RUNNING = 1) it is recommended to alter the
firmware to use mode 0. Thus ensuring the CLKOUT pin “Lazy clock” is enabled and the SUSPEND
pin is logic 1 during suspend mode.
For designs originally using mode 3, (NO LAZY CLOCK =1 and CLOCK RUNNNIG = 1) the SUSPEND
pin will not drive high as per USBD12 designs.
Firmware can be modified to set the CLOCK RUNNING bit of Set Mode command to be ‘0’ (Mode 0
or Mode 2). Under this configuration the CLKOUT will switch to 30 kHz suspend clock upon
entering USB suspend state. To resume the USB bus, firmware needs to wakeup FT120 by drive
the SUSPEND pin to LOW, and then issue Send Resume command to FT120.
10
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Application Note
AN_209 PDIUSBD12 to FT120 Migration Guide
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6 IO Levels
The FT120 has been designed to be used in 3V3 systems. The IO pins are designed to drive out at
3V3 levels, but support input levels from 3V3 to 5V.
In many systems 3V3 output will be sufficient to drive 5V logic, but in other cases it may require
additional logic to boost the logic level.
The PDIUSBD12 device was designed to operate in 3V3 to 5V systems and as such is capable of
driving out at 3V3 to 5V levels.
11
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Application Note
AN_209 PDIUSBD12 to FT120 Migration Guide
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7 Ordering Information.
Part Number
FT120T-00-U
Package
28 Pin TSSOP, Tube
Table 7.1 Part numbers
12
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AN_209 PDIUSBD12 to FT120 Migration Guide
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8 Summary
Updating an existing design from a PDIUSBD12 to the FT120 should be a simple process, requiring
a small BOM change ie swap the PDIUSBD12 out for the FT120T. All existing and proven firmware
shall run on the new FT120T as it did on the original device. This solution allows for a rapid
upgrade to ensure designs which may have been deemed obsolete due to supply difficulties with
the original parts can enjoy an extended life span.
13
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AN_209 PDIUSBD12 to FT120 Migration Guide
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9 Contact Information
Head Office – Glasgow, UK
Branch Office – Hillsboro, Oregon, USA
Future Technology Devices International Limited
Unit 1, 2 Seaward Place, Centurion Business Park
Glasgow G41 1HH
United Kingdom
Tel: +44 (0) 141 429 2777
Fax: +44 (0) 141 429 2758
7130 SW Fir Loop
Tigard, OR 97223-8160
USA
Tel: +1 (503) 547 0988
Fax: +1 (503) 547 0987
E-mail (Sales)
E-mail (Support)
E-mail (General Enquiries)
E-Mail (Sales)
E-Mail (Support)
E-Mail (General Enquiries)
[email protected]
[email protected]
[email protected]
Branch Office – Shanghai, China
Branch Office – Taipei, Taiwan
Room 1103, No. 666 West Huaihai Road,
Shanghai, 200052
China
Tel: +86 21 62351596
Fax: +86 21 62351595
2F, No. 516, Sec. 1, NeiHu Road
Taipei 114
Taiwan , R.O.C.
Tel: +886 (0) 2 8797 1330
Fax: +886 (0) 2 8751 9737
E-mail (Sales)
E-mail (Support)
E-mail (General Enquiries)
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
E-mail (Sales)
E-mail (Support)
E-mail (General Enquiries)
[email protected]
[email protected]
[email protected]
Web Site
http://ftdichip.com
System and equipment manufacturers and designers are responsible to ensure that their systems, and any Future Technology
Devices International Ltd (FTDI) devices incorporated in their systems, meet all applicable safety, regulatory and system-level
performance requirements. All application-related information in this document (including application descriptions, suggested
FTDI devices and other materials) is provided for reference only. While FTDI has taken care to assure it is accurate, this
information is subject to customer confirmation, and FTDI disclaims all liability for system designs and for any applications
assistance provided by FTDI. Use of FTDI devices in life support and/or safety applications is entirely at the user’s risk, and the
user agrees to defend, indemnify and hold harmless FTDI from any and all damages, claims, suits or expense resulting from
such use. This document is subject to change without notice. No freedom to use patents or other intellectual property rights is
implied by the publication of this document. Neither the whole nor any part of the information contained in, or the product
described in this document, may be adapted or reproduced in any material or electronic form without the prior written consent
of the copyright holder. Future Technology Devices International Ltd, Unit 1, 2 Seaward Place, Centurion Business Park,
Glasgow G41 1HH, United Kingdom. Scotland Registered Company Number: SC136640
14
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Appendix A – References
Document References
FT120 Data Sheet
Acronyms and Abbreviations
Terms
Description
DMA
Direct Memory Access
USB
Universal Serial Bus
15
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Appendix B – List of Tables & Figures
List of Tables
Table
Table
Table
Table
Table
2.1
2.2
5.1
5.2
6.1
Feature comparison ............................................................................................... 3
Pinout comparison ................................................................................................ 5
Register list .......................................................................................................... 9
Clock Modes ....................................................................................................... 10
Part numbers ..................................................................................................... 12
List of Figures
Figure 3.1 Reference Schematic ............................................................................................ 6
16
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Appendix C – Revision History
Document Title:
Document Reference No.:
Clearance No.:
Product Page:
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http://www.ftdichip.com/FTProducts.htm
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Changes
Initial Release
Added section 6 on IO levels
Update contact info
Date
2012-M05-08
2012-12-14
17
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