TI TUSB3410

Data Manual
NOTE
Designing with this device may require extensive support. Before incorporating this device into
a design, customers should contact TI or an Authorized TI Distributor.
June 2002
MSP USB
SLLS519B
IMPORTANT NOTICE
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Copyright  2002, Texas Instruments Incorporated
Contents
Section
1
2
3
4
Title
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.1
Controller Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Main Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.1
USB Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2
General Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3
Enhanced UART Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.4
Pinout Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Detailed Controller Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1
Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2
USB Interface Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2.1
External Memory Case . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2.2
Host Download Case . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3
USB Data Movement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.4
Serial Port Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5
Serial Port Data Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5.1
RS-232 Data Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5.2
RS-485 Data Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5.3
IrDA Data Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
MCU Memory Map (Internal Operation) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.1
Miscellaneous Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.1.1
ROMS: ROM Shadow Configuration Register
(Addr:FF90) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.1.2
Boot Operation (MCU Firmware Loading) . . . . . . . . . . . . . .
4.1.3
WDCSR: Watchdog Timer, Control, and Status Register
(Addr:FF93) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.2
Buffers + I/O RAM Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.3
Endpoint Descriptor Block (EDB–1 to EDB–3) . . . . . . . . . . . . . . . . . . .
4.3.1
OEPCNF_n: Output Endpoint Configuration (n = 1 to 3)
(Addr:FF08, FF10, FF18) . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.3.2
OEPBBAX_n: Output Endpoint X-Buffer Base Address
(n = 1 to 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.3.3
OEPBCTX_n: Output Endpoint X Byte Count
(n = 1 to 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.3.4
OEPBBAY_n: Output Endpoint Y-Buffer Base Address
(n = 1 to 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.3.5
OEPBCTY_n: Output Endpoint Y-Byte Count
(n = 1 to 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.3.6
OEPSIZXY_n: Output Endpoint X-/Y-Buffer Size
(n =1 to 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Page
1–1
1–1
2–1
2–1
2–1
2–1
2–2
3–1
3–1
3–1
3–1
3–1
3–1
3–1
3–2
3–2
3–2
3–2
4–1
4–2
4–2
4–2
4–3
4–3
4–5
4–6
4–6
4–7
4–7
4–7
4–8
iii
4.3.7
5
iv
IEPCNF_n: Input Endpoint Configuration (n = 1 to 3)
(Addr:FF48, FF50, FF58) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–8
4.3.8
IEPBBAX_n: Input Endpoint X-buffer Base Address
(n = 1 to 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–8
4.3.9
IEPBCTX_n: Input Endpoint X-Byte Count (n = 1 to 3) . . . 4–9
4.3.10
IEPBBAY_n: Input Endpoint Y-Buffer Base Address
(n = 1 to 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–9
4.3.11
IEPBCTY_n: Input Endpoint Y-Byte Count (n = 1 to 3) . . . 4–9
4.3.12
IEPSIZXY_n: Output Endpoint X-/Y-Buffer Size
(n = 1 to 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–10
4.4
Endpoint-0 Descriptor Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–10
4.4.1
IEPCNFG_0: Input Endpoint-0 Configuration Register
(Addr:FF80) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–10
4.4.2
IEPBCNT_0: Input Endpoint-0 Byte Count Register
(Addr:FF81) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–10
4.4.3
OEPCNFG_0: Output Endpoint-0 Configuration Register
(Addr:FF82) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–11
4.4.4
OEPBCNT_0: Output Endpoint-0 Byte Count Register
(Addr:FF83) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–11
USB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–1
5.1
USB Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–1
5.1.1
FUNADR: Function Address Register (Addr:FFFF) . . . . . . 5–1
5.1.2
USBSTA: USB Status Register (Addr:FFFE) . . . . . . . . . . . 5–1
5.1.3
USBMSK: USB Interrupt Mask Register (Addr:FFFD) . . . . 5–2
5.1.4
USBCTL: USB Control Register (Addr:FFFC) . . . . . . . . . . . 5–3
5.1.5
MODECNFG: Mode Configuration Register (Addr:FFFB) 5–4
5.1.6
Vendor ID/Product ID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–4
5.1.7
SERNUM7: Device Serial Number Register (Byte 7)
(Addr:FFEF) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–4
5.1.8
SERNUM6: Device Serial Number Register (Byte 6)
(Addr:FFEE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–5
5.1.9
SERNUM5: Device Serial Number Register (Byte 5)
(Addr:FFED) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–5
5.1.10
SERNUM4: Device Serial Number Register (Byte 4)
(Addr:FFEC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–6
5.1.11
SERNUM3: Device Serial Number Register (Byte 3)
(Addr:FFEB) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–6
5.1.12
SERNUM2: Device Serial Number Register (Byte 2)
(Addr:FFEA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–6
5.1.13
SERNUM1: Device Serial Number Register (Byte 1)
(Addr:FFE9) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–6
5.1.14
SERNUM0: Device Serial Number Register (Byte 0)
(Addr:FFE8) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–7
5.1.15
Function Reset And Power-Up Reset Interconnect . . . . . . 5–7
5.1.16
Pullup Resistor Connect/Disconnect . . . . . . . . . . . . . . . . . . 5–8
6
7
8
9
DMA Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–1
6.1
DMA Controller Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–1
6.1.1
DMACDR1: DMA Channel Definition Register (UART Transmit
Channel) (Addr:FFE0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–2
6.1.2
DMACSR1: DMA Control And Status Register (UART Transmit
Channel) (Addr:FFE1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–3
6.1.3
DMACDR3: DMA Channel Definition Register (UART Receive
Channel) (Addr:FFE4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–4
6.1.4
DMACSR3: DMA Control And Status Register (UART Receive
Channel) (Addr:FFE5) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–5
6.2
Bulk Data I/O Using the EDB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–5
6.2.1
IN Transaction (TUSB3410 to Host) . . . . . . . . . . . . . . . . . . . 6–5
6.2.2
OUT Transaction (Host to TUSB3410) . . . . . . . . . . . . . . . . . 6–6
UART . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–1
7.1
UART Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–1
7.1.1
RDR: Receiver Data Register (Addr:FFA0) . . . . . . . . . . . . . 7–1
7.1.2
TDR: Transmitter Data Register (Addr:FFA1) . . . . . . . . . . . 7–1
7.1.3
LCR: Line Control Register (Addr:FFA2) . . . . . . . . . . . . . . . 7–2
7.1.4
FCRL: UART Flow Control Register (Addr:FFA3) . . . . . . . . 7–3
7.1.5
Transmitter Flow Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–4
7.1.6
MCR: Modem-Control Register (Addr:FFA4) . . . . . . . . . . . . 7–5
7.1.7
LSR: Line-status Register (Addr:FFA5) . . . . . . . . . . . . . . . . 7–6
7.1.8
MSR: Modem-Status Register (Addr:FFA6) . . . . . . . . . . . . 7–7
7.1.9
DLL: Divisor Register Low Byte (Addr:FFA7) . . . . . . . . . . . 7–8
7.1.10
DLH: Divisor Register High Byte (Addr:FFA8) . . . . . . . . . . . 7–8
7.1.11
Baud-rate Calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–8
7.1.12
XON: Xon Register (Addr:FFA9) . . . . . . . . . . . . . . . . . . . . . . 7–9
7.1.13
XOFF: Xoff Register (Addr:FFAA) . . . . . . . . . . . . . . . . . . . . . 7–9
7.1.14
MASK: UART Interrupt-Mask Register (Addr:FFAB) . . . . . 7–10
7.2
UART Data Transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–10
7.2.1
Receiver Data Flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–10
7.2.2
Hardware Flow Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–11
7.2.3
Auto RTS (Receiver Control) . . . . . . . . . . . . . . . . . . . . . . . . . 7–11
7.2.4
Auto CTS (Transmitter Control) . . . . . . . . . . . . . . . . . . . . . . . 7–11
7.2.5
Xon/Xoff Receiver Flow Control . . . . . . . . . . . . . . . . . . . . . . . 7–12
7.2.6
Xon/Xoff Transmit Flow Control . . . . . . . . . . . . . . . . . . . . . . . 7–12
Expanded GPIO Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8–1
8.1
Input/Output and Control Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8–1
8.1.1
PUR_3: GPIO Pullup Register For Port 3 (Addr:FF9E) . . . 8–1
Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–1
9.1
8052 Interrupt and Status Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–1
9.1.1
8052 Standard Interrupt Enable (SIE) Register . . . . . . . . . 9–1
9.1.2
Additional Interrupt Sources . . . . . . . . . . . . . . . . . . . . . . . . . . 9–1
9.1.3
VECINT: Vector Interrupt Register (Addr:FF92) . . . . . . . . . 9–2
9.1.4
Logical Interrupt Connection Diagram (Internal/External) . 9–3
v
10
I2C-Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–1
10.1 I2C Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–1
10.1.1
I2CSTA: I2C Status and Control Register (Addr:FFF0) . . . 10–1
10.1.2
I2CADR: I2C Address Register (Addr:FFF3) . . . . . . . . . . . . 10–2
10.1.3
I2CDAI: I2C Data-Input Register (Addr:FFF2) . . . . . . . . . . 10–2
10.1.4
I2CDAO: I2C Data-Output Register (Addr:FFF1) . . . . . . . . 10–2
10.2 Random-Read Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–2
10.3 Current-Address Read Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–3
10.4 Sequential-Read Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–3
10.5 Byte-Write Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–4
10.6 Page-Write Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–5
11 TUSB3410 Bootcode Flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–1
11.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–1
11.2 Bootcode Programming Flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–1
11.3 Default Bootcode Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–2
11.3.1
Device Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–3
11.3.2
Configuration Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–3
11.3.3
Interface Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–4
11.3.4
Endpoint Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–4
11.3.5
String Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–5
11.4 External Device Header Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–6
11.4.1
Product Signature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–6
11.4.2
Descriptor Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–7
11.4.2.1
Descriptor Prefix . . . . . . . . . . . . . . . . . . . . . . . . 11–7
11.4.2.2
Descriptor Content . . . . . . . . . . . . . . . . . . . . . . 11–7
11.5 Checksum in Descriptor Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–7
11.6 Header Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–7
11.6.1
TUSB3410 Bootcode Supported Descriptor Block . . . . . 11–7
11.6.2
USB Descriptor Header . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–8
11.6.3
Autoexec Binary Firmware . . . . . . . . . . . . . . . . . . . . . . . . . 11–10
11.7 Host Driver Downloading Header Format . . . . . . . . . . . . . . . . . . . . . 11–10
11.8 Built-In Vendor Specific USB Requests . . . . . . . . . . . . . . . . . . . . . . . 11–11
11.8.1
Reboot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–11
11.8.2
Force Execute Firmware . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–11
11.8.3
External Memory Read . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–11
11.8.4
External Memory Write . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–11
11.8.5
I2C Memory Read . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–12
11.8.6
I2C Memory Write . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–12
11.8.7
Internal ROM Memory Read . . . . . . . . . . . . . . . . . . . . . . . 11–12
11.9 Bootcode Programming Consideration . . . . . . . . . . . . . . . . . . . . . . . 11–13
11.9.1
USB Requests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–13
11.9.2
Hardware Reset Introduced by Firmware . . . . . . . . . . . . 11–16
11.10 File Listings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–16
12 Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12–1
vi
12.1
12.2
12.3
Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Commercial Operating Condition (3.3 V) . . . . . . . . . . . . . . . . . . . . . . .
Electrical Characteristics TA = 255C, VCC = 3.3 V +5%,
VSS = 0 V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
13 Application Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
13.1 Crystal Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
13.2 External Circuit Required for Reliable Bus Powered Suspend
Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
14 Mechanical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12–1
12–1
12–1
13–1
13–1
13–1
14–1
vii
List of Illustrations
Figure
Title
Page
1–1 Controller Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–1
1–2 USB-to-Serial (Single Channel) Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–2
3–1 RS-232 and IR Mode Select . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–3
3–2 USB-to-Serial Implementation (RS-232) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–4
3–3 RS-485 Bus Implementation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–4
4–1 MCU Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–1
5–1 Reset Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–7
5–2 Pullup Resistor Connect/Disconnect Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . 5–8
6–1 Transaction Time-Out Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–3
7–1 MSR and MCR Registers in Loop-Back Mode . . . . . . . . . . . . . . . . . . . . . . . . 7–7
7–2 Receiver/Transmitter Data Flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–11
7–3 Auto Flow Control Interconnect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–11
9–1 Internal Vector Interrupt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–3
11–1 Control Read Transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–13
11–2 Control Write Transfer Without Data Stage . . . . . . . . . . . . . . . . . . . . . . . . . 11–14
13–1 Crystal Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13–1
13–2 External Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13–1
viii
List of Tables
Table
Title
Page
2–1 Terminal Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–4
4–1 ROM/RAM Size Definition Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–2
4–2 XDATA Space . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–3
4–3 Memory Mapped Registers Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–4
4–4 EDB Memory Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–5
4–5 EDB Entries in RAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–6
4–6 Input/Output EDB-0 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–10
6–1 DMA Controller Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–1
6–2 DMA OUT-Termination Condition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–3
6–3 DMA IN-Termination Condition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–5
7–1 UART Registers Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–1
7–2 Transmitter Flow-Control Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–4
7–3 Receiver Flow-Control Possibilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–4
7–4 DLL/DLH Values and Resulted Baud Rates . . . . . . . . . . . . . . . . . . . . . . . . . . 7–9
9–1 8052 Interrupt Location Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–1
9–2 Vector Interrupt Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–2
11–1 Device Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–3
11–2 Configuration Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–3
11–3 Interface Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–4
11–4 Output Endpoint1 Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–4
11–5 String Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–5
11–6 USB Descriptors Header . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–8
11–7 Autoexec Binary Firmware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–10
11–8 Host Driver Downloading Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–10
11–9 Bootcode Response to Control Read Transfer . . . . . . . . . . . . . . . . . . . . . . 11–14
11–10 Bootcode Response to Control Write Without Data Stage . . . . . . . . . . . 11–14
11–11 Vector Interrupt Values and Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–15
ix
x
1 Introduction
1.1 Controller Description
The TUSB3410 provides bridging between a USB port and an enhanced UART serial port. The TUSB3410 contains
all the necessary logic to communicate with the host computer using the USB bus. It contains an 8052 microcontroller
unit (MCU) with 16K bytes of RAM that can be loaded from the host or from external on-board memory via an I2C
bus. It also contains 10K bytes of ROM that allow the MCU to configure the USB port at boot time. The ROM code
also contains an I2C boot loader. All the device functions such as the USB command decoding, UART setup, and error
reporting are managed by the internal MCU firmware under the auspices of the PC host.
The TUSB3410 can be used to build an interface between a legacy serial peripheral device and a PC with USB ports,
such as a legacy-free PC. Once configured, data flows from the host to the TUSB3410 via USB OUT commands and
then out from the TUSB3410 on the SOUT line. Conversely, data flows into the TUSB3410 on the SIN line and then
into the host via USB IN commands.
Out
SOUT
Host
(PC or OTG DRD)
USB
TUSB3410
In
Legacy
Serial
Peripheral
SIN
Figure 1–1. Data Flow
1–1
12 MHz
Clock
Oscillator
PLL
and
Dividers
DP, DM
8052
Core
24 MHz
10K × 8
ROM
USB
TxR
16K × 8
RAM
2K × 8
SRAM
8
8
2 × 16-Bit
Timers
8
8
4
Port 3
P3.(4, 3,1,0)
8
8
I2C
Controller
I2C Bus
8
DMA-1
DMA-3
8
CPU-I/F
Susp./Res.
USB
SIE
8
8
UBM
USB Buffer
Manager
8
RTS
CTS
DTR
DSR
UART–1
SIN
SOUT
TDM
Control
Logic
IR
Encoder
M
U
X
M
U
X
IR
Encoder
Figure 1–2. USB-to-Serial (Single Channel) Controller Block Diagram
1–2
SOUT/IR_SO
SIN/IR_SIN
2 Main Features
2.1 USB Features
•
•
•
•
•
Fully compliant with USB 2.0 full speed Specifications
Supports 12-Mbps USB data rate (full speed)
Supports USB suspend, resume, and remote wakeup operations
Supports two power source modes:
– Bus-powered mode
– Self-powered mode
Can support a total of 3-input and 3-output (interrupt, bulk) endpoints
2.2 General Features
•
•
•
•
•
•
•
Integrated 8052 microcontroller with
– 256 × 8 RAM for internal data
– 10K × 8 ROM (with USB and I2C boot loader)
– 16K × 8 RAM for code space loadable from host or I2C port
– 2K × 8 Shared RAM used for data buffers and endpoint descriptor blocks (EDB)
– Four GPIO pins from 8052 port 3
– Master I2C controller for EEPROM device access
– MCU operates at 24 MHz providing 2 MIPS operation
– 128-ms Watchdog Timer
Built-in two-channel DMA controller for USB/UART bulk I/O
Operates from a 12-MHz crystal
Supports USB suspend and resume
Supports remote wake-up
Available in 32-pin LQFP
3.3-V operation with 1.8-V core operating voltage provided by on-chip 1.8-V voltage regulator
2.3 Enhanced UART Features
•
•
•
•
•
•
Software/hardware flow control:
– Programmable Xon/Xoff characters
– Programmable Auto-RTS/DTR and Auto-CTS/DSR
Automatic RS485-bus transceiver control, with and without echo
Selectable IrDA mode for up to 115.2 kbps transfer
Software selectable baud rate from 50 to 921.6 k baud
Programmable serial-interface characteristics
–
5-, 6-, 7-, or 8-Bit characters
–
Even, odd, or no parity-bit generation and detection
– 1-, 1.5-, or 2-Stop bit generation
Line break generation and detection
2–1
•
•
•
Internal test and loop-back capabilities
Modem-control functions (CTS, RTS, DSR, DTR, RI, and DCD)
Internal diagnostics capability
– Loopback control for communications link-fault isolation
– Break, parity, overrun, framing-error simulation
2.4 Pinout Information
TEST1
TEST0
CLKOUT
DTR
RTS
SOUT/IR_SOUT
GND
SIN/IR_SIN
VF PACKAGE
(TOP VIEW)
24 23 22 21 20 19 18 17
VCC
X2
X1/CLK1
GND
P3.4
P3.3
P3.1
P3.0
25
16
26
15
27
14
28
13
29
12
30
11
31
10
32
9
VREGEN
SUSPEND
VCC
VDD18
PUR
DP
DM
GND
1 2 3 4 5 6 7 8
2–2
RI/CP
DCD
DSR
CTS
WAKEUP
SCL
SDA
RESET
Table 2–1. Terminal Functions
TERMINAL
NAME
NO.
I/O
DESCRIPTION
CLKOUT
22
O
Clock output (controlled by CLKOUTEN and CLKSLCT in MODECNFG register (see Section 5.1.5
and Note 1)
CTS
13
I
UART: Clear to send (see Note 4)
DCD
15
I
UART: Data carrier detect (see Note 4)
DM
7
I/O
Upstream USB port differential data minus
DP
6
I/O
Upstream USB port differential data plus
DSR
14
I
UART: Data set ready (see Note 4)
DTR
21
O
UART: Data terminal ready (see Note 1)
GND
8, 18, 28
GND
P3.0
32
I/O
Port-3.0 (see Notes 3, 4, 5, and 8)
P3.1
31
I/O
Port-3.1 (see Notes 3, 4, 5, and 8)
P3.3
30
I/O
Port-3.3 (see Notes 3, 4, 5, and 8)
P3.4
29
I/O
Port-3.4 (see Notes 3, 4, 5, and 8)
PUR
5
O
Pull-up resistor connection (see Note 2)
RESET
9
I
Controller master reset signal (see Note 4)
RI/CP
16
I
UART: Ring indicator (see Note 4)
RTS
20
O
SCL
11
O
UART: Request to send (see Note 1)
Master I2C controller: clock signal (see Note 1)
SDA
10
I/O
Master I2C controller: data signal (see Notes 1 and 5)
SIN/IR_SIN
17
I
UART: Serial input data / IR Serial data input (see Note 6)
SOUT/IR_SOUT
19
O
UART: Serial output data / IR Serial data output (see Note 7)
SUSPEND
2
O
Suspend condition signal (see Note 3)
TEST0
23
I
Test input (for factory test only) (see Note 5)
TEST1
24
I
Test input (for factory test only) (see Note 5)
VCC
VDD18
3, 25
4
Digital ground
PWR 3.3 V
PWR 1.8-V Supply. An internal voltage regulator generates this supply voltage when terminal VREGEN
is asserted. When VREGEN is deasserted, 1.8 V must be supplied externally.
VREGEN
1
I
This active-low terminal is used to enable the 3.3-V to 1.8-V voltage regulator in the core.
WAKEUP
12
I
Remote wake-up request pin. When low, wakes up system (see Note 5)
X1/CLKI
27
I
12-MHz crystal input or clock input
X2
26
O
12-MHz crystal output
NOTES: 1.
2.
3.
4.
5.
6.
7.
8.
3-state CMOS output (±4-mA drive/sink)
3-state CMOS output (±8-mA drive/sink)
3-state CMOS output (±12-mA drive/sink)
TTL-compatible, hysteresis input
TTL-compatible, hysteresis input, with internal 100-µA active pullup
TTL-compatible input without hysteresis, with internal 100-µA active pullup
Normal or IR mode: 3-state CMOS output (±4-mA drive/sink)
The MCU treats the outputs as open drain types in that the output can be driven low continuously, but a high output is driven for two
clock cycles and then the output is tristated.
2–3
2–4
3 Detailed Controller Description
3.1 Operating Modes
The TUSB3410 controls its USB interface in response to USB commands, and this action remains the same
independent of the serial port mode selected. On the other hand, the serial port can be set up in three modes.
As with any interface device, data movement is the TUSB3410’s main function, but typically the initial configuration
and error handling consume most of the support code. The following sections describe the various modes the device
can be used in and the means of setting up the device.
3.2 USB Interface Configuration
The TUSB3410 contains onboard ROM microcode, which enables the MCU to enumerate the device as a USB
peripheral. The ROM microcode can also load application code into internal RAM from either external memory via
the I2C bus or from the host via the USB.
3.2.1
External Memory Case
After reset, the TUSB3410 is disconnected from the USB because the pullup resistor CONT bit is cleared. The
TUSB3410 checks the I2C port for the existence of valid code, if it finds valid code, it uploads the code from the
external memory device into the RAM program space. Once loaded, the TUSB3410 connects to the USB by setting
the CONT bit and enumeration and configuration are performed. This is the most likely use of the device.
3.2.2
Host Download Case
If the valid code is not found at the I2C port, the TUSB3410 connects to the USB by setting the CONT bit, and then
an enumeration and default configuration are performed. The host can then download additional microcode into RAM
to tailor the application. Then, the MCU causes a disconnect and reconnect by using the pullup resistor CONT bit
in the USBCTL register, which causes the TUSB3410 to be re-enumerated with a new configuration.
3.3 USB Data Movement
From the USB perspective, the TUSB3410 looks like a USB peripheral device. It uses endpoint 0 as its control
endpoint, as do all USB peripherals. It also configures up to three input and three output endpoints, although most
applications use one bulk input endpoint for data in, one bulk output endpoint for data out, and one interrupt endpoint
for status updates. The USB configuration likely remains the same regardless of the serial port configuration.
Most data is moved from the USB side to the UART side and vice versa using on-chip DMA transfers. Some special
cases may use programmed IO under control of the MCU.
3.4 Serial Port Setup
The serial port requires a few control registers to be written to configure its operation. This configuration likely remains
the same regardless of the data mode used. These registers include the line control register that controls the serial
word format and the divisor registers that control the baud rate.
These registers are usually controlled by the host application.
3.5 Serial Port Data Modes
The serial port can be configured in three different, although similar, data modes. Similar to the USB mode, once
configured for a specific application, it is unlikely that the mode would be changed. The different modes affect the
timing of the serial input and output or the use of the control signals. However, the basic serial-to-parallel conversion
3–1
of the receiver and parallel-to-serial conversion of the transmitter remain the same in all modes. Some features are
available in all modes, but are only applicable in certain modes. For instance, software flow control via Xoff/Xon
characters can be used in all modes, but would usually only be used in RS-232 or IrDA mode because the RS-485
mode is half-duplex communication. Similarly, hardware flow control via RTS/CTS (or DTR/DSR) handshaking is
available in RS-232 or IrDA mode. However, this would probably be used only in RS-232 mode, since in IrDA mode
only the SIN and SOUT paths are optically coupled.
3.5.1
RS-232 Data Mode
The default mode is called the RS-232 mode, and is usually used for full duplex communication on SOUT and SIN.
In this mode, the modem control outputs (RTS and DTR) are used to communicate to a modem or as general outputs.
The modem control inputs (CTS, DSR, DCD, and RI) are used for modem communication or as general inputs.
Alternatively, RTS and CTS (or DTR and DSR) can be used to throttle the data flow on SOUT and SIN to prevent
receive fifo overruns. Finally, software flow control via Xoff/Xon characters can be used for the same purpose.
This mode represents the most general-purpose applications, and the other modes are subsets of this mode.
3.5.2
RS-485 Data Mode
The RS-485 mode is very similar to the RS-232 mode in that the SOUT and SIN formats remain the same. Since
RS-485 is a bus architecture, it is inherently a single duplex communication system. The TUSB3410 in RS-485 mode
controls the RTS and DTR signals such that either can be used to enable an RS-485 driver or RS-485 receiver. When
in RS-485 mode, the enable signals for transmitting are automatically asserted whenever the DMA is set up for
outbound data. The receiver can be left enabled while the driver is enabled to allow an echo if desired, but when
receive data is expected, the driver must be disabled. Note that this precludes use of hardware flow control, since
this is a half duplex operation, it would not be effective anyhow. Software flow control is supported, but may be of
limited value.
The RS-485 mode is enabled by setting the 485E bit in the FCRL register, and a receiver enable (RCVE) bit in the
MCR allows the receiver to eavesdrop while in 485 mode.
3.5.3
IrDA Data Mode
The IrDA mode encodes SOUT and decodes SIN in the manner prescribed by the IrDA standard, up to 115.2 kbps.
Connection to an external IrDA transceiver is required. Communications is usually full duplex. Generally in an IrDA
system only the SOUT and SIN paths are connected, so hardware flow control is usually not an option. Software flow
control is supported.
The IrDA mode is enabled by setting the IREN bit in the USB control register.
The IR encoder and decoder circuitry work with the UART to change the serial bit stream into a series of pulses and
back again. For every zero bit in the outbound serial stream, the encoder sends a low-to-high-to-low pulse with the
duration of 3/16 of a bit frame at the middle of the bit time. For every one bit in the serial stream, the output remains
low for the entire bit time.
The decoding process consists of receiving the signal from the IrDA receiver and converting it to a series of zeroes
and ones. As the converse to the encoder, the decoder converts a pulse to a zero bit and the lack of a pulse to a one
bit.
3–2
SOUT
0
M
U
X
From
UART
SOUT
IR_TX
IR
Encoder
SOUT/IR_SOUT
1
IREN
0
UART
BaudOut
Clock
M
U
X
SOFTSW
1
TXCNTL
0
M
U
X
3.556 MHz
CLKOUT Pin
CLKOUTEN
1
CLKSLCT
3.3 V
0
To
UART
Receiver
SIN
M
U
X
1
IR_RX
IR
Decoder
SIN/IR_SIN Pin
Figure 3–1. RS-232 and IR Mode Select
3–3
DB9
Connector
Transceivers
12 MHz
DTR
4
RTS
7
RI
DCD
1
DSR
6
CTS
8
SOUT
3
SIN
2
Serial Port
USB-0
TUSB3410
P3.0
P3.1
P3.3
P3.4
GPIO Pins for
Other Onboard
Control Function
Figure 3–2. USB-to-Serial Implementation (RS-232)
12 MHz
RTS
RS-485 Bus
SOUT
DTR
SIN
USB-0
TUSB3410
RS-485
Transceiver
2-Bits Time
1-Bit Max
SOUT
DTR
RTS
Receiver is Disabled if RCVE = 0
Figure 3–3. RS-485 Bus Implementation
3–4
4 MCU Memory Map (Internal Operation)
Figure 4–1 illustrates the MCU memory map under boot and normal operation. For more information regarding the
integrated 8052, see the TUSBxxxx Microcontroller Reference Guide (SLLU044).
NOTE:
The internal 256 bytes of RAM are not shown, since they are assumed to be in the standard
8052 location (0000 to 00FF). The shaded areas represent the internal ROM/RAM.
When SDW bit = 0 (boot mode): The 10K ROM is mapped to address (0x0000–0x27FF) and is duplicated in location
(0x8000–0xA7FF) in code space. The internal 16K RAM is mapped to address range (0x0000–0x3FFF) in data
space. Buffers, MMR, and I/O are mapped to address range (0xF800–0xFFFF) in data space.
When SDW bit = 1 (normal mode): The 10K ROM is mapped to (0x8000–0xA7FF) in code space. The internal 166K
RAM is mapped to address range (0x0000–0x3FFFF) in code space. Buffers, MMR, and I/O are mapped to address
range (0xF800–0xFFFF) in data space.
CODE
Boot Mode (SDW = 0)
XDATA
Normal Mode (SDW = 1)
CODE
XDATA
0000
10K Boot ROM
(16K)
Read/Write
16K
Code RAM
Read Only
27FF
3FFF
8000
10K Boot ROM
10K Boot ROM
A7FF
F800
FF7F
FF80
FFFF
2K Data
2K Data
MMR
MMR
Figure 4–1. MCU Memory Map
4–1
4.1 Miscellaneous Registers
4.1.1
ROMS: ROM Shadow Configuration Register (Addr:FF90)
This register is used by the MCU to switch from boot mode to normal operation mode (boot mode is set on power-on
reset only). In addition, this register provides the device revision number and the ROM/RAM configuration.
7
6
5
4
3
2
1
0
ROA
S1
S0
R3
R2
R1
R0
SDW
R/O
R/O
R/O
R/O
R/O
R/O
R/O
R/W
BIT
0
NAME
SDW
RESET
0
FUNCTION
This bit enables/disables boot ROM. (Shadow the ROM).
SDW = 0
When clear, the MCU executes from the 10K boot-ROM space. The boot ROM appears in two
locations: 0000 and 8000h. The 16K RAM is mapped to XDATA space; therefore, read/write
operation is possible. This bit is set by the MCU after the RAM load is completed. MCU cannot
clear this bit; it is cleared on power-up reset or watchdog time-out reset.
SDW = 1
When set by the MCU, the 10K boot-ROM maps to location 8000h, and the 16K RAM is mapped
to code space, starting at location 0000h. At this point, the MCU executes from RAM, and the
write operation is disabled (no write operation is possible in code space).
4–1
R[3:0]
No effect
These bits reflect the device revision number.
6–5
S[1:0]
No effect
Code space size. These bits define the ROM or RAM code-space size (ROA bit defines ROM or RAM).
These bits are permanently set and are not affected by reset (see Table 4–1).
00 = 4K bytes code space size
01 = 8K bytes code space size
10 = 16K bytes code space size
11 = 32K bytes code space size
7
ROA
No effect
ROM or RAM version. This bit indicates whether the code space is RAM or ROM based. This bit is
permanently set and is not affected by reset (see Table 4–1).
ROA = 0 Code space is ROM
ROA = 1 Code space is RAM
Table 4–1. ROM/RAM Size Definition Table
ROMS REGISTER
4.1.2
BOOT ROM
RAM CODE
ROM CODE
0
None
None
4K
0
1
None
None
8K
1
0
None
None
16K (reserved)
1
1
1
None
None
32K (reserved)
1
0
0
10K
4K
None
1
0
1
10K
8K
None
1
1
0
10K
16K
None
1
1
1
10K
32K (reserved)
None
ROA
S1
S0
0
0
0
0
Boot Operation (MCU Firmware Loading)
Since the code space is in RAM (with the exception of the boot ROM), the TUSB3410 firmware must be loaded from
an external source. Two sources are available for booting: one from an external serial E2PROM connected to the I2C
bus and the other from the host via the USB. On device reset, the SDW bit (in ROMS register) and CONT bit (in
USBCTL: USB control register) are cleared. This configures the memory space to boot mode (see Memory Map) and
keeps the device disconnected from the host. The first instruction is fetched from location 0000h (which is in the 10K
ROM). The 16K RAM is mapped to XDATA space (location 0000h). The MCU executes a read from an external
E2PROM and tests whether it contains the code (by testing for boot signature). If it contains the code, the MCU reads
from E2PROM and writes to the 16K RAM in XDATA space. If it does not contain the code, the MCU proceeds to boot
from the USB.
4–2
Once the code is loaded, the MCU sets SDW = 1. This switches the memory map to normal mode; i.e. the 16K RAM
is mapped to code space, and the MCU starts executing from location 0000h. Once the switch is done, the MCU sets
CONT = 1 (in the USBCTL register). This connects the device to the USB and results in normal USB device
enumeration.
4.1.3
WDCSR: Watchdog Timer, Control, and Status Register (Addr:FF93)
A watchdog timer (WDT) with 1-ms clock is provided. If this register is not accessed for a period of 128 ms, the WDT
counter resets the MCU. (see Figure 5–1). The watchdog timer is enabled by default and can be disabled by writing
a pattern of 101010 into the WDD[5:0] bits.
7
6
5
4
3
2
1
0
ROA
S1
S0
R3
R2
R1
R0
SDW
R/W
R/W
R/W
R/W
R/W
R/W
R/W
W/O
BIT
0
5–1
6
7
NAME
RESET
FUNCTION
WDT
0
MCU must write a 1 to this bit to prevent the WDT from resetting the MCU. If MCU does not write a 1
in a period of 128 ms, the WDT resets the device. Writing a 0 has no effect on the WDT. (WDT is a
7-bit counter using a 1-ms CLK). This bit is read as 0.
WDD[5:1]
00000
These bits are used to disable the watchdog timer. For the timer to be disabled these bits must be set
to 10101 and WDD[0] must also be set to 0. If any other pattern is present, the watchdog timer is in
operation.
WDR
0
Watchdog reset indication bit. This bit indicates if the reset occurred due to power-on reset or
watchdog timer reset.
WDD[0]
1
WDR = 0
A power-up reset occurred
WDR = 1
A USB reset or watchdog time-out reset occurred. To clear this bit, the MCU must write a 1.
Writing a 0 has no effect.
This bit is one of the disable bits for the watchdog timer. This bit must be cleared in order for the
watchdog timer to be disabled.
4.2 Buffers + I/O RAM Map
The address range from F800 to FFFF (2K bytes) is reserved for data buffers, setup packet, endpoint descriptors
block (EDB), and all I/O. There are 128 locations reserved for MMR (memory mapped registers). Table 4–2
represents the XDATA space allocation and access restriction for the DMA, UBM, and MCU.
Table 4–2. XDATA Space
DESCRIPTION
ADDRESS RANGE
UBM ACCESS
DMA ACCESS
MCU ACCESS
Internal MMRs
(Memory Mapped Registers)
FFFF
↑
FF80
No
(Only EDB-0)
No
(only Data reg. and EDB-0)
Yes
EDB
(Endpoint Descriptors Block)
FF7F
↑
FF08
Only for EDB update
Only for EDB update
Yes
Setup Packet
FF07
↑
FF00
Yes
No
Yes
Input Endpoint-0 Buffer
FEFF
↑
FEF8
Yes
Yes
Yes
Output Endpoint-0 Buffer
FEF7
↑
FEF0
Yes
Yes
Yes
Data Buffers
FEEF
↑
F800
Yes
Yes
Yes
4–3
Table 4–3. Memory Mapped Registers Summary (XDATA Range = FF80 → FFFF)
ADDRESS
DESCRIPTION
FFFF
FUNADR
Function address register
FFFE
USBSTA
USB status register
FFFD
USBMSK
USB interrupt mask register
FFFC
USBCTL
USB control register
FFFB
MODECNFG
Mode configuration register
FFFA
DEVVIDH
Device custom VID high byte register
FFF9
DEVVIDL
Device custom VID low byte register
FFF8
DEVPIDH
Device custom PID high byte register
FFF7
DEVPIDL
Device custom PID low byte register
FFF6
DEVREVH
Device custom revision number high byte register
FFF5
DEVREVL
Device custom revision number low byte register
↑
4–4
REGISTER
RESERVED
FFF3
I2CADR
FFF2
I2CDATI
FFF1
I2CDATO
I2C-port address register
I2C-port data input register
FFF0
I2CSTA
I2C-port data output register
I2C-port status register
FFEF
SERNUM7
Serial number byte 7 register
FFEE
SERNUM6
Serial number byte 6 register
FFED
SERNUM5
Serial umber byte 5 register
FFEC
SERNUM4
Serial number byte 4 register
FFEB
SERNUM3
Serial number byte 3 register
FFEA
SERNUM2
Serial number byte 2 register
FFE9
SERNUM1
Serial number byte 1 register
FFE8
SERNUM0
Serial number byte 0 register
↑
RESERVED
FFE5
DMACSR3
DMA–3: Control and status register
FFE4
DMACDR3
DMA–3: Channel definition register
↑
RESERVED
FFE1
DMACSR1
DMA–1: Control and status register
FFE0
DMACDR1
DMA–1: Channel definition register
↑
RESERVED
FFAB
MASK
UART: Interrupt mask register
FFAA
XOFF
UART: Xoff register
FFA9
XON
UART: Xon register
FFA8
DLH
UART: Divisor high-byte register
FFA7
DLL
UART: Divisor low-byte register
FFA6
MSR
UART: Modem status register
FFA5
LSR
UART: Line status register
FFA4
MCR
UART: Modem control register
FFA3
FCRL
UART: Flow control register
FFA2
LCR
UART: Line control registers
FFA1
TDR
UART: Transmitter data registers
FFA0
RDR
UART: Receiver data registers
FF9E
PUR_3
GPIO: Pullup register for port 3
Table 4–3. Memory Mapped Registers Summary (XDATA Range = FF80 → FFFF) (Continued)
ADDRESS
REGISTER
DESCRIPTION
↑
FF93
RESERVED
WDCSR
Watchdog timer control and status register
FF92
VECINT
Vector interrupt register
↑
FF90
RESERVED
ROMS
ROM shadow configuration register
↑
RESERVED
FF83
OEPBCNT_0
Output endpoint_0: Byte count register
FF82
OEPCNFG_0
Output endpoint_0: Configuration register
FF81
IEPBCNT_0
Input endpoint_0: Byte count register
FF80
IEPCNFG_0
Input endpoint_0: Configuration register
Table 4–4. EDB Memory Locations
ADDRESS
↑
REGISTER
DESCRIPTION
RESERVED
FF58
IEPCNF_3
Input endpoint_3: Configuration
FF50
IEPCNF_2
Input endpoint_2: Configuration
FF48
IEPCNF_1
Input endpoint_1: Configuration
FF47
↑
RESERVED
FF20
FF18
OEPCNF_3
Output endpoint_3: Configuration
FF10
OEPCNF_2
Output endpoint_2: Configuration
FF08
OEPCNF_1
Output endpoint_1: Configuration
(8 bytes)
Setup packet block
(8 bytes)
Input endpoint-0 buffer
(8 bytes)
Output endpoint-0 buffer
TOPBUFF
Top of buffer space
FF07
↑
FF00
FEFF
↑
FEF8
FEF7
↑
FEF0
FEEF
↑
F800
Buffer space
STABUFF
Start of buffer space
4.3 Endpoint Descriptor Block (EDB–1 to EDB–3)
Data transfers between the USB, the MCU, and external devices that are defined by an endpoint descriptor Block
(EDB). Three input- and three output-EDBs are provided. With the exception of EDB–0 (I/O endpoint–0), all EDBs
are located in SRAM as per Table 4–3. Each EDB contains information describing the X- and Y-buffers. In addition,
each EDB provides general status information.
Table 4–5 illustrates the EDB entries for EDB–1 to EDB–3. EDB–0 registers are described separately.
4–5
Table 4–5. EDB Entries in RAM (n = 1 to 3)
OFFSET
4.3.1
ENTRY NAME
07
EPSIZXY_n
I/O Endpoint_n: X/Y-buffer size
06
EPBCTY_n
I/O Endpoint_n: Y-byte count
05
EPBBAY_n
I/O Endpoint_n: Y-buffer base address
04
SPARE
Not used
03
SPARE
Not used
02
EPBCTX_n
I/O Endpoint_n: X-byte count
01
EPBBAX_n
I/O Endpoint_n: X-buffer base address
00
EPCNF_n
I/O Endpoint_n: Configuration
OEPCNF_n: Output Endpoint Configuration (n = 1 to 3) (Addr:FF08, FF10, FF18)
7
6
5
4
3
2
1
0
UBME
ISO=0
TOGLE
DBUF
STALL
USBIE
RSV
RSV
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
BIT
NAME
1–0
RESET
FUNCTION
RSV
x
Reserved = 0
2
USBIE
x
USB interrupt enable on transaction completion. Set/cleared by the MCU
USBIE = 0 No interrupt
USBIE = 1 Interrupt on transaction completion
3
STALL
0
USB stall condition indication. Set/cleared by the MCU
STALL = 0
Stall = 1
No stall
USB stall condition. If set by the MCU, a STALL handshake is initiated and the bit is cleared
by the MCU.
4
DBUF
x
Double-buffer enable. Set/cleared by the MCU
DBUF = 0 Primary buffer only (X-buffer only)
DBUF = 1 Toggle bit selects buffer
5
TOGLE
x
USB toggle bit. This bit reflects the toggle sequence bit of DATA0, DATA1
6
ISO
x
ISO = 0 Nonisochronous transfer. This bit must be cleared by the MCU since only nonisochronous transfer
is supported
7
UBME
x
UBM enable/disable bit. Set/cleared by the MCU
UBME = 0 UBM cannot use this endpoint
UBME = 1 UBM can use this endpoint
4.3.2
OEPBBAX_n: Output Endpoint X-Buffer Base Address (n = 1 to 3)
7
6
5
4
3
2
1
0
A10
A9
A8
A7
A6
A5
A4
A3
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
BIT
7–0
4–6
DESCRIPTION
NAME
A[10:3]
RESET
FUNCTION
x
A[10:3] of X-buffer base address (padded with 3 LSB of zeros for a total of 11 bits). This value is set by the
MCU. The UBM or DMA uses this value as the start-address of a given transaction. Note that the UBM or
DMA does not change this value at the end of a transaction.
4.3.3
OEPBCTX_n: Output Endpoint X Byte Count (n = 1 to 3)
7
6
5
4
3
2
1
0
NAK
C6
C5
C4
C3
C2
C1
C0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
NAME
BIT
6–0
7
4.3.4
FUNCTION
x
X-buffer byte count:
X000.0000b Count = 0
X000.0001b Count = 1 byte
:
:
X011.1111b Count = 63 bytes
X100.0000b Count = 64 bytes
Any value ≥ 100.0001b may result in unpredictable results.
NAK
x
NAK =0
NAK = 1
No valid data in buffer. Ready for host OUT
Buffer contains a valid packet from host (gives NAK response to Host OUT request)
OEPBBAY_n: Output Endpoint Y-Buffer Base Address (n = 1 to 3)
7
6
5
4
3
2
1
0
A10
A9
A8
A7
A6
A5
A4
A3
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
BIT
NAME
7–0
RESET
FUNCTION
x
A[10:3] of Y-buffer base address (padded with 3 LSB of zeros for a total of 11 bits). This value is set by the
MCU. The UBM or DMA uses this value as the start-address of a given transaction. Furthermore, UBM or
DMA does not change this value at the end of a transaction.
A[10:3]
4.3.5
OEPBCTY_n: Output Endpoint Y-Byte Count (n = 1 to 3)
7
6
5
4
3
2
1
0
NAK
C6
C5
C4
C3
C2
C1
C0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
BIT
6–0
7
RESET
C[6:0]
NAME
RESET
FUNCTION
C[6:0]
x
Y-byte count:
X000.0000b Count = 0
X000.0001b Count = 1 byte
:
:
X011.1111b Count = 63 bytes
X100.0000b Count = 64 bytes
Any value ≥ 100.0001b may result in unpredictable results.
NAK
x
NAK =0
NAK = 1
No valid data in buffer. Ready for host OUT
Buffer contains a valid packet from host (gives NAK response to Host OUT request)
4–7
4.3.6
OEPSIZXY_n: Output Endpoint X-/Y-Buffer Size (n =1 to 3)
7
6
5
4
3
2
1
0
RSV
S6
S5
S4
S3
S2
S1
S0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
NAME
BIT
6–0
7
4.3.7
FUNCTION
x
X- and Y-buffer size:
0000.0000b Size = 0
0000.0001b Size = 1 byte
:
:
0011.1111b Size = 63 bytes
0100.0000b Size = 64 bytes
Any value ≥ 100.0001b may result in unpredictable results.
RSV
x
Reserved = 0
IEPCNF_n: Input Endpoint Configuration (n = 1 to 3) (Addr:FF48, FF50, FF58)
7
6
5
4
3
2
1
0
UBME
ISO=0
TOGLE
DBUF
STALL
USBIE
RSV
RSV
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
NAME
BIT
1–0
RESET
FUNCTION
RSV
x
Reserved = 0
2
USBIE
x
USB interrupt enable on transaction completion
USBIE = 0 No interrupt
USBIE = 1 Interrupt on transaction completion
3
STALL
0
USB stall condition indication. Set by the UBM but can be set/cleared by the MCU
STALL = 0 No stall
STALL = 1 USB stall condition. If set by the MCU a STALL handshake is initiated and the bit is cleared
automatically.
4
DBUF
x
Double buffer enable
DBUF = 0 Primary buffer only (X-buffer only)
DBUF = 1 Toggle bit selects buffer
5
TOGLE
x
USB toggle bit. This bit reflects the toggle sequence bit of DATA0, DATA1
6
ISO
x
ISO = 0 Nonisochronous transfer. This bit must be cleared by the MCU since only nonisochronous
transfer is supported
7
UBME
x
UBM enable/disable bit. Set/cleared by the MCU
UBME = 0 UBM cannot use this endpoint
UBME = 1 UBM can use this endpoint
4.3.8
IEPBBAX_n: Input Endpoint X-buffer Base Address (n = 1 to 3)
7
6
5
4
3
2
1
0
A10
A9
A8
A7
A6
A5
A4
A3
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
BIT
7–0
4–8
RESET
C[6:0]
NAME
A[10:3]
RESET
FUNCTION
x
A[10:3] of X-buffer base address (padded with 3 LSB of zeros for a total of 11 bits). This value is set by the
MCU. The UBM or DMA uses this value as the start-address of a given transaction, but note that the UBM
or DMA does not change this value at the end of a transaction.
4.3.9
IEPBCTX_n: Input Endpoint X-Byte Count (n = 1 to 3)
7
6
5
4
3
2
1
0
NAK
C6
C5
C4
C3
C2
C1
C0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
NAME
BIT
6–0
7
RESET
FUNCTION
C[6:0]
x
X-Buffer byte count:
X000.0000b Count = 0
X000.0001b Count = 1 byte
:
:
X011.1111b Count = 63 bytes
X100.0000b Count = 64 bytes
Any value ≥ 100.0001b may result in unpredictable results.
NAK
x
NAK = 0
NAK = 1
Buffer contains a valid packet for host-IN transaction
Buffer is empty (gives NAK response to host-OUT request)
4.3.10 IEPBBAY_n: Input Endpoint Y-Buffer Base Address (n = 1 to 3)
7
6
5
4
3
2
1
0
A10
A9
A8
A7
A6
A5
A4
A3
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
BIT
NAME
7–0
RESET
FUNCTION
x
A[10:3] of Y-buffer base address (padded with 3 LSB of zeros for a total of 11 bits). This value is set by the
MCU. The UBM or DMA uses this value as the start-address of a given transaction, but note that the UBM
or DMA does not change this value at the end of a transaction.
A[10:3]
4.3.11 IEPBCTY_n: Input Endpoint Y-Byte Count (n = 1 to 3)
7
5
4
3
2
1
0
NAK
C6
C5
C4
C3
C2
C1
C0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
BIT
6–0
7
6
NAME
RESET
FUNCTION
C[6:0]
x
Y-Byte count:
X000.0000b Count = 0
X000.0001b Count = 1 byte
:
:
X011.1111b Count = 63 bytes
X100.0000b Count = 64 bytes
Any value ≥ 100.0001b may result in unpredictable results.
NAK
x
NAK =0
NAK = 1
Buffer contains a valid packet for host-IN transaction
Buffer is empty (gives NAK response to host-IN request)
4–9
4.3.12 IEPSIZXY_n: Output Endpoint X-/Y-Buffer Size (n = 1 to 3)
7
6
5
4
3
2
1
0
RSV
S6
S5
S4
S3
S2
S1
S0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
BIT
NAME
6–0
7
RESET
FUNCTION
C[6:0]
x
X- and Y-buffer size:
0000.0000b Size = 0
0000.0001b Size = 1 byte
:
:
0011.1111b Size = 63 bytes
0100.0000b Size = 64 bytes
Any value ≥ 100.0001b may result in unpredictable results.
RSV
x
Reserved = 0
4.4 Endpoint-0 Descriptor Registers
Unlike registers EDB–1 to EDB–3, which are defined as memory entries in SRAM, endpoint–0 is described by a set
of four registers (two for output and two for input). The registers and their respective addresses, used for EDB–0
description, are defined in Table 4–6. EDB–0 has no base-address register, since these addresses are hardwired into
FEF8 and FEF0. Note that the bit positions have been preserved to provide consistency with EDB–n (n = 1 to 3).
Table 4–6. Input/Output EDB-0 Registers
ADDRESS
4.4.1
DESCRIPTION
BASE ADDRESS
OEPBCNT_0
OEPCNFG_0
Output endpoint_0: Byte count register
Output endpoint_0: Configuration register
FEF0
FF81
FF80
IEPBCNT_0
IEPCNFG_0
Output endpoint_0: Byte count register
Output endpoint_0: Configuration register
FEF8
IEPCNFG_0: Input Endpoint-0 Configuration Register (Addr:FF80)
7
6
5
4
3
2
1
0
UBME
RSV
TOGLE
RSV
STALL
USBIE
RSV
RSV
R/W
R/O
R/O
R/O
R/W
R/W
R/O
R/O
BIT
NAME
1–0
RESET
FUNCTION
RSV
0
Reserved = 0
2
USBIE
0
USB interrupt enable on transaction completion. Set/cleared by the MCU.
USBIE = 0 No interrupt
USBIE = 1 Interrupt on transaction completion
3
STALL
0
USB stall condition indication. Set/cleared by the MCU
STALL = 0 No stall
STALL = 1 USB stall condition. If set by the MCU a STALL handshake is initiated and the bit is cleared
automatically by the next setup transaction.
4
RSV
0
Double buffer enable
DBUF = 0 Primary buffer only (X-buffer only)
DBUF = 1 Toggle bit selects buffer
5
TOGLE
0
USB toggle bit. This bit reflects the toggle sequence bit of DATA0, DATA1.
6
RSV
0
Reserved = 0
7
UBME
0
UBM enable/disable bit. Set/cleared by the MCU
UBME = 0 UBM cannot use this endpoint
UBME = 1 UBM can use this endpoint
4.4.2
IEPBCNT_0: Input Endpoint-0 Byte Count Register (Addr:FF81)
7
4–10
REGISTER NAME
FF83
FF82
6
5
4
3
2
1
0
NAK
RSV
RSV
RSV
C3
C2
C1
C0
R/W
R/O
R/O
R/O
R/W
R/W
R/W
R/W
BIT
NAME
3–0
C[3:0]
0h
Byte count:
0000b Count = 0
:
:
1111b Count = 7
1000b Count = 8
1001b to 1111b are reserved. (If used, they default to 8)
6–4
rsv
0
Reserved = 0
NAK
1
NAK =0
NAK = 1
7
4.4.3
RESET
FUNCTION
Buffer contains a valid packet for host-IN transaction
Buffer is empty (gives NAK response to host-IN request)
OEPCNFG_0: Output Endpoint-0 Configuration Register (Addr:FF82)
7
6
5
4
3
2
1
0
UBME
RSV
TOGLE
RSV
STALL
USBIE
RSV
RSV
R/W
R/O
R/O
R/O
R/W
R/W
R/O
R/O
BIT
NAME
1–0
RSV
0
Reserved = 0
2
USBIE
0
USB interrupt enable on transaction completion. Set/cleared by the MCU.
USBIE = 0 No interrupt
USBIE = 1 Interrupt on transaction completion
3
STALL
0
USB stall condition indication. Set/cleared by the MCU
STALL = 0 No stall
STALL = 1 USB stall condition. If set by the MCU, a STALL handshake is initiated and the bit is cleared
automatically.
4
RSV
0
Reserved = 0
5
TOGLE
0
USB \toggle bit. This bit reflects the toggle sequence bit of DATA0, DATA1.
6
RSV
0
Reserved = 0
7
UBME
0
UBM enable/disable bit. Set/cleared by the MCU
UBME = 0 UBM cannot use this endpoint
UBME = 1 UBM can use this endpoint
4.4.4
RESET
FUNCTION
OEPBCNT_0: Output Endpoint-0 Byte Count Register (Addr:FF83)
7
6
5
4
NAK
RSV
RSV
RSV
C3
C2
C1
C0
R/W
R/O
R/O
R/O
R/O
R/O
R/O
R/O
BIT
NAME
3–0
C[3:0]
0h
Byte count:
0000b Count = 0
:
:
1111b Count = 7
1000b Count = 8
1001b to 1111b are reserved
6–4
rsv
0
Reserved = 0
NAK
1
NAK =0
NAK = 1
7
RESET
3
2
1
0
FUNCTION
No valid data in buffer. Ready for host OUT
Buffer contains a valid packet from host (gives NAK response to host-IN request).
4–11
4–12
5 USB
5.1 USB Registers
5.1.1
FUNADR: Function Address Register (Addr:FFFF)
This register contains the device function address.
7
6
5
4
3
2
1
0
RSV
FA6
FA5
FA4
FA3
FA2
FA1
FA0
R/O
R/W
R/W
R/W
R/W
R/W
R/W
R/W
RESET
FUNCTION
FA[6:0]
NAME
0
These bits define the current device address assigned to the function. The MCU writes a value to this
register because of the SET-ADDRESS host command.
RSV
0
Reserved = 0
BIT
6–0
7
5.1.2
USBSTA: USB Status Register (Addr:FFFE)
All bits in this register are set by the hardware and are cleared by the MCU when writing a 1 to the proper bit location
(writing a 0 has no effect). In addition, each bit can generate an interrupt if its corresponding mask bit is set (R/C
notation indicates read and clear only by the MCU).
7
6
5
4
3
2
1
0
RSTR
SUSR
RESR
RSV
URRI
SETUP
WAKEUP
STPOW
R/C
R/C
R/C
R/O
R/C
R/C
R/C
R/C
BIT
0
NAME
STPOW
RESET
FUNCTION
0
SETUP Overwrite bit. Set by hardware when setup packet is received while there is already a packet in
the setup buffer.
STPOW = 0
STPOW = 1
1
WAKEUP
0
Remote wakeup bit
WAKEUP = 0
WAKEUP = 1
2
SETUP
0
URRI
0
The MCU can clear this bit by writing a 1 (writing 0 has no effect).
Remote wakeup request from WAKEUP pin
SETUP transaction received bit. As long as SETUP is 1, IN and OUT on endpoint–0 are NAKed,
regardless of their real NAK bits value.
SETUP = 0
SETUP = 1
3
MCU can clear this bit by writing a 1 (writing 0 has no effect).
SETUP overwrite
MCU can clear this bit by writing a 1 (writing 0 has no effect).
SETUP transaction received
UART RI status bit – a rising edge causes this bit to be set.
URRI = 0
URRI = 1
URRI = 0 The MCU can clear this bit by writing a 1 (writing 0 has no effect).
URRI = 1 Ring detected, which is used to wake the chip up (bring it out of suspend).
4
RSV
0
Reserved
5
RESR
0
Function resume request bit
RESR = 0
RESR = 1
6
SUSR
0
Function suspended request bit. This bit is set in response to a global or selective suspend condition.
FSUSP = 0
FSUSP = 1
7
RSTR
0
The MCU can clear this bit by writing a 1 (writing 0 has no effect).
Function resume is detected
The MCU can clear this bit by writing a 1 (writing 0 has no effect).
Function suspend is detected
Function reset request bit. This bit is set in response to host initiating a port reset. This bit is not
affected by the USB function reset.
FRST = 0
FRST = 1
The MCU can clear this bit by writing a 1 (writing 0 has no effect).
Function reset is detected
5–1
5.1.3
USBMSK: USB Interrupt Mask Register (Addr:FFFD)
7
6
5
4
3
2
1
0
RSTR
SUSR
RESR
RSV
UR1RI
SETUP
WAKEUP
STPOW
R/W
R/W
R/W
R/O
R/W
R/W
R/W
R/W
BIT
0
NAME
STPOW
RESET
0
FUNCTION
SETUP overwrite interrupt-enable bit
STPOW = 0
STPOW = 1
1
WAKEUP
0
Remote wakeup interrupt enable bit
WAKEUP = 0
WAKEUP = 1
2
SETUP
0
UR1RI
0
SETUP interrupt disabled
SETUP interrupt enabled
UART 1 R1 interrupt enable bit
URRI = 0
URRI = 1
UR1RI interrupt disable
UR1RI interrupt enable
4
RSV
0
Reserved
5
RESR
0
Function resume interrupt enable bit
RESR = 0
RESR = 1
6
SUSR
0
7
RSTR
0
Function resume interrupt disabled
Function resume interrupt enabled
Function suspend interrupt enable
FSUSP = 0
FSUSP = 1
Function suspend interrupt disabled
Function suspend interrupt enabled
Function reset interrupt bit. This bit is not affected by USB function reset.
FRST = 0
FRST = 1
5–2
WAKEUP interrupt disable
WAKEUP interrupt enable
SETUP interrupt enable bit
SETUP = 0
SETUP = 1
3
STPOW interrupt disabled
STPOW interrupt enabled
Function reset interrupt disabled
Function reset interrupt enabled
5.1.4
USBCTL: USB Control Register (Addr:FFFC)
Unlike the rest of the registers, this register is cleared by the power-up reset signal only. The USB reset cannot reset
this register (see Figure 5–1).
BIT
0
7
6
5
4
3
2
1
0
R/W
R/O
R/W
R/W
R/W
R/O
R/W
R/W
NAME
DIR
RESET
0
As a response to a setup packet, the MCU decodes the request and sets/clears this bit to reflect the data transfer
direction.
DIR = 0
DIR = 1
1
SIR
0
USB data-OUT transaction (from host to TUSB3410)
USB data-IN transaction (from TUSB3410 to host)
SETUP interrupt-status bit. This bit is controlled by the MCU to indicate to the hardware when the SETUP interrupt
is being served.
SIR = 0
SIR = 1
SETUP interrupt is not served. The MCU clears this bit before exiting the SETUP interrupt routine.
SETUP interrupt is in progress. The MCU sets this bit when servicing the SETUP interrupt.
2
RSV
0
Reserved = 0
3
RSV
0
Reserved = 0
4
FRSTE
1
Function reset-connection bit. This bit connects/disconnects the USB function reset to/from the MCU reset.
FRSTE = 0
FRSTE = 1
5
RWUP
0
Device remote wakeup request. This bit is set by the MCU and is cleared automatically.
RWUP = 0
RWUP = 1
6
IREN
0
CONT
0
Writing a 0 to this bit has no effect
When MCU writes a 1, a remote-wakeup pulse is generated.
IR mode enable. This bit is set and cleared by firmware.
IREN = 0
IREN = 1
7
Function reset is not connected to MCU reset
Function reset is connected to MCU reset
IR encoder/decoder is disabled, UART mode is selected
IR encoder/decoder is enabled, UART mode is deselected
Connect/disconnect bit
CONT = 0
CONT = 1
Upstream port is disconnected. Pullup disabled.
Upstream port is connected. Pullup enabled.
5–3
5.1.5
MODECNFG: Mode Configuration Register (Addr:FFFB)
This register is cleared by the power-up reset signal only. The USB reset cannot reset this register.
7
6
5
4
3
2
1
0
RSV
RSV
RSV
RSV
CLKSLCT
CLKOUTEN
SOFTSW
TXCNTL
R/O
R/O
R/O
R/O
R/W
R/W
R/W
R/W
NAME
BIT
0
RESET
TXCNTL
0
FUNCTION
Transmit output control: Hardware or firmware switching select for 3-state serial output buffer.
TXCNTL = 0
TXCNTL = 1
1
SOFTSW
0
Soft switch: Firmware controllable 3-state output buffer enable for serial output pin.
SOFTSW = 0
SOFTSW = 1
2
CLKOUTEN
0
CLKSLCT
0
RSV
0
Clock output is disabled. Device drives low at CLKOUT terminal.
Clock output is enabled
Clock output source select: Select between 3.556-MHz fixed clock or UART baud out clock as output
clock source.
CLKSLCT = 0
CLKSLCT = 1
4–7
Serial output buffer is enabled
Serial output buffer is disabled
Clock output enable: Enable/disable the clock output at CLKOUT terminal.
CLKOUTEN = 0
CLKOUTEN = 1
3
Hardware automatic switching is selected
Firmware toggle switching is selected
UART baud out clock is selected as clock output
Fixed 3.556-MHz free running clock is selected as clock output
Reserved
Clock Output Control
The CLKOUTEN bit in the Mode Configuration Register (MODECNFG) is used to enable or disable the clock output
at the CLKOUT terminal of the TUSB3410. The power up default of CLKOUT is disabled to ensure the clock is not
applied to the smart card until it is powered. Firmware can write a 1 to enable the clock output if needed.
The CLKSLCT bit in the MODECNFG register is used to select the output clock source from either a fixed 3.556-MHz
free-running clock or the UART BaudOut clock.
5.1.6
Vendor ID/Product ID
USB–IF and Microsoft WHQL certification requires that end equipment makers use their own unique vendor ID and
product ID for each product (model). OEMs cannot use silicon vendor’s (for instance, TI’s default) VID/PID in their
end products. A unique VID/PID combination will avoid potential driver conflicts and enable logo certification. See
www.usb.org for more information.
5.1.7
SERNUM7: Device Serial Number Register (Byte 7) (Addr:FFEF)
Each TUSB3410 chip has a unique 64-bit serial die id number, which is generated during manufacturing. The die id
is incremented sequentially, however there is no assurance without skip in the die id number. The device serial
number register utilizes (mirrors) this unique 64-bit serial die id number.
After power-up reset, this read-only register (SERNUM7) contains the most significant byte (byte 7) of the complete
64-bit device serial number. The USB reset cannot reset this register.
7
6
5
4
3
2
1
0
D63
D62
D61
D60
D59
D58
D57
D56
R/O
R/O
R/O
R/O
R/O
R/O
R/O
R/O
BIT
7–0
5–4
NAME
D[7:0]
RESET
Device serial number byte 7 value
FUNCTION
Device serial number byte 7 value
Procedure to load device serial number value in shared RAM:
•
After power-up reset, boot code copies the predefined USB descriptors to shared RAM. As a result, the
default serial number hard-coded in the boot code (0x00 hex) is copied to the shared RAM data space.
•
Once the boot code finishes copying descriptors, it performs a read to the SERNUM7 to SERNUM0
registers and overwrites the device serial number value stored in the shared RAM with the one found in the
SERNUM7 to SERNUM0 registers.
•
Once the boot code finishes the read to SERNUM7 – SERNUM0 registers, it then checks if EEPROM is
present on the I2C port. If the EEPROM is present and contains a valid device serial number as part of the
USB device descriptor information stored in EEPROM, the boot code overwrites the serial number value
stored in shared RAM with the one found in EEPROM. Otherwise, the device serial number value stored
in shared RAM stays unchanged from previous step.
•
In summary, the serial number value in external EEPROM has the highest priority to be loaded into shared
RAM data space. The serial number value stored in shared RAM is used as part of the valid device
descriptor information during normal operation.
5.1.8
SERNUM6: Device Serial Number Register (Byte 6) (Addr:FFEE)
The device serial number register utilizes (mirrors) this unique 64-bit serial die id number.
After power-up reset, this read-only register (SERNUM6) contains byte 6 of the complete 64-bit device serial number.
The USB reset cannot reset this register.
7
6
5
4
3
2
1
0
D55
D54
D53
D52
D51
D50
D49
D48
R/O
R/O
R/O
R/O
R/O
R/O
R/O
R/O
BIT
NAME
7–0
RESET
D[7:0]
FUNCTION
Device serial number byte 6 value
Device serial number byte 6 value
NOTE: See the same procedure described in SERNUM7 register for procedure to load device serial number into the shared RAM.
5.1.9
SERNUM5: Device Serial Number Register (Byte 5) (Addr:FFED)
The device serial number register utilizes (mirrors) this unique 64-bit serial die id number.
After power-up reset, this read-only register (SERNUM5) contains byte 5 of the complete 64-bit device serial number.
The USB reset cannot reset this register.
7
6
5
4
3
2
1
0
D47
D46
D45
D44
D43
D42
D41
D40
R/O
R/O
R/O
R/O
R/O
R/O
R/O
R/O
BIT
7–0
NAME
D[7:0]
RESET
Device serial number byte 5 value
FUNCTION
Device serial number byte 5 value
NOTE: See the same procedure described in SERNUM7 register for procedure to load device serial number into the shared RAM.
5–5
5.1.10 SERNUM4: Device Serial Number Register (Byte 4) (Addr:FFEC)
The device serial number register utilizes (mirrors) this unique 64-bit serial die id number.
After power-up reset, this read-only register (SERNUM4) contains byte 4 of the complete 64-bit device serial number.
The USB reset cannot reset this register.
7
6
5
4
3
2
1
0
D39
D38
D37
D36
D35
D34
D33
D32
R/O
R/O
R/O
R/O
R/O
R/O
R/O
R/O
NAME
BIT
7–0
RESET
D[7:0]
FUNCTION
Device serial number byte 4 value
Device serial number byte 4 value
NOTE: See the same procedure described in SERNUM7 register for procedure to load device serial number into the shared RAM.
5.1.11 SERNUM3: Device Serial Number Register (Byte 3) (Addr:FFEB)
The device serial number register utilizes (mirrors) this unique 64-bit serial die id number.
After power-up reset, this read-only register (SERNUM3) contains byte 3 of the complete 64-bit device serial number.
The USB reset cannot reset this register.
7
6
5
4
3
2
1
0
D31
D30
D29
D28
D27
D26
D25
D24
R/O
R/O
R/O
R/O
R/O
R/O
R/O
R/O
NAME
BIT
7–0
RESET
D[7:0]
FUNCTION
Device serial number byte 3 value
Device serial number byte 3 value
NOTE: See the same procedure described in SERNUM7 register for procedure to load device serial number into the shared RAM.
5.1.12 SERNUM2: Device Serial Number Register (Byte 2) (Addr:FFEA)
The device serial number register utilizes (mirrors) this unique 64-bit serial die id number.
After power-up reset, this read-only register (SERNUM2) contains byte 2 of the complete 64-bit device serial number.
The USB reset cannot reset this register.
7
6
5
4
3
2
1
0
D23
D22
D21
D20
D19
D18
D17
D16
R/O
R/O
R/O
R/O
R/O
R/O
R/O
R/O
BIT
NAME
7–0
RESET
D[7:0]
FUNCTION
0
Device serial number byte 2 value
NOTE: See the same procedure described in SERNUM7 register for procedure to load device serial number into the shared RAM.
5.1.13 SERNUM1: Device Serial Number Register (Byte 1) (Addr:FFE9)
The device serial number register utilizes (mirrors) this unique 64-bit serial die id number.
After power-up reset, this read-only register (SERNUM1) contains byte 1 of the complete 64-bit device serial number.
The USB reset cannot reset this register.
7
6
5
4
3
2
1
0
D15
D14
D13
D12
D11
D10
D9
D8
R/O
R/O
R/O
R/O
R/O
R/O
R/O
R/O
BIT
7–0
NAME
D[7:0]
RESET
Device serial number byte 1 value
FUNCTION
Device serial number byte 1 value
NOTE: See the same procedure described in SERNUM7 register for procedure to load device serial number into the shared RAM.
5–6
5.1.14 SERNUM0: Device Serial Number Register (Byte 0) (Addr:FFE8)
The device serial number register utilizes (mirrors) this unique 64-bit serial die id number.
After power-up reset, this read-only register (SERNUM0) contains byte 0 of the complete 64-bit device serial number.
The USB reset cannot reset this register.
7
6
5
4
3
2
1
0
D7
D6
D5
D4
D3
D2
D1
D0
R/O
R/O
R/O
R/O
R/O
R/O
R/O
R/O
BIT
7–0
NAME
D[7:0]
RESET
FUNCTION
Device serial number byte 0 value
Device serial number byte 0 value
NOTE: See the same procedure described in SERNUM7 register for procedure to load device serial number into the shared RAM.
5.1.15 Function Reset And Power-Up Reset Interconnect
Figure 5–1 represents the logical connection of the USB-function reset (USBR) and power-up reset (RESET) pins.
The internal RESET signal is generated from the RESET pin (PURS signal) or from the USB reset (USBR signal).
The USBR can be enabled or disabled by the FRSTE bit in the USBCTL register (on power up, FRSTE = 0). The
internal RESET is used to reset all registers and logic, with the exception of the USBCTL and GLOBCTL registers
which are cleared by the PURS signal only.
USBCTL Register
GLOBCTL Register
To Internal MMRs
MCU
RESET
PURS
RESET
USBR
G2
USB Function Reset
FRSTE
WDT Reset
WDD[4:0]
Figure 5–1. Reset Diagram
5–7
5.1.16 Pullup Resistor Connect/Disconnect
The TUSB3410 enumeration can be activated by the MCU (there is no need to disconnect the cable physically).
Figure 5–2 represents the implementation of the TUSB3410 connect and disconnect from a USB up-stream port.
When CONT = 1 in the USBCTL register, the CMOS driver sources VDD to the pullup resistor (PUR pin) presenting
a normal connect condition to the USB hub (high speed). When CONT = 0, the PUR pin is driven low. In this state,
the 1.5-kΩ resistor is connected to GND, resulting in the device disconnection state. The PUR driver is a CMOS driver
that can provide (VDD – 0.1 V) minimum at 8-mA source current.
PUR
CMOS
CONT-Bit
1.5 kΩ
HUB
D+
DP0
D–
DM0
15 kΩ
TUSB3410
Figure 5–2. Pullup Resistor Connect/Disconnect Circuit
5–8
6 DMA Controller
Table 6–1 outlines the DMA channels and their associated transfer directions. Two channels are provided for data
transfer between the host and the UART.
Table 6–1. DMA Controller Registers
DMA CHANNEL
TRANSFER DIRECTION
COMMENTS
DMA–1
Host to UART
DMA writes to UART TDR register
DMA–3
UART to host
DMA reads from UART RDR register
6.1 DMA Controller Registers
Each DMA channel can point to one of three EDBs (EDB[3:1]) and transfer data to/from the UART channel. The DMA
can move data from a given out-point buffer (defined by EDB) to the destination port. Similarly, the DMA can move
data from a port to a given input-endpoint buffer. Two modes of DMA transfers are supported: burst and continuous.
•
Burst (CNT = 0) Mode
The DMA stops at the end of a block-data transfer (or if an error condition occurred) and interrupts the MCU.
It is the responsibility of the MCU to update the X/Y bit and the NAK bit in the EDB.
•
Continuous (CNT = 1) Mode
At the end of a block transfer the DMA updates the byte count and NAK bit in the EDB when receiving. In
addition, it uses the X/Y bit to switch automatically, without interrupting the MCU (the X/Y bit toggle is
performed by the UBM). The DMA stops only when a time-out or error condition occurs. When the DMA is
transmitting (from the X/Y buffer) it continues alternating between X/Y buffers until it detects a byte count
smaller than the buffer size (buffer size is typically 64 bytes). At that point it completes the transfer and stops.
6–1
6.1.1
DMACDR1: DMA Channel Definition Register (UART Transmit Channel) (Addr:FFE0)
These registers are used to define the EDB number that the DMA uses for data transfer to the UARTS. In addition,
these registers define the data transfer direction and selects X or Y as the transaction buffer.
7
6
5
4
3
2
1
0
EN
INE
CNT
XY
T/R
E2
E1
E0
R/W
R/W
R/W
R/W
R/O
R/W
R/W
R/W
BIT
NAME
RESET
2–0
E[2:0]
0
Endpoint descriptor pointer. This field points to a set of EDB registers that is to be used for a given transfer.
3
T/R
0
This bit is always zero, indicating that the DMA data transfer is from SRAM to the UART TDR register. (The MCU
cannot change this bit.)
4
XY
0
X/Y buffer select bit. Valid only when CNT = 0
FUNCTION
XY = 0
XY = 1
5
6
7
6–2
CNT
INE
EN
0
0
0
Next buffer to transmit/receive is the X buffer
Next buffer to transmit/receive is the Y buffer
DMA continuous transfer control bit. This bit defines the mode of the DMA transfer.
CNT = 0
Burst mode: The DMA stops the transfer when the byte count is zero or when a partial packet has been
received (byte count < 64). At the end of transfer, the high-to-low transition of EN interrupts the MCU (if
enabled). In this mode, the X/Y bit is set by the MCU to define the current buffer (X or Y).
CNT = 1
Continuous mode: In this mode, the DMA and UBM alternate between the X- and Y-buffers. The DMA
sets the X/Y bit and the UBM uses it for the transfer. The DMA alternates between the X-/Y-buffers and
continues transmitting (from X-/Y-buffer) without MCU intervention. The DMA terminates, and interrupts
the MCU, under the following conditions:
1. When the UBM byte count < buffer size (in EDB), the DMA transfers the partial packet and interrupt
the MCU on completion.
2. Transaction timer expires. The DMA interrupts the MCU.
DMA Interrupt enable/disable bit. This bit is used to enable/disable the interrupt on transfer completion.
INE = 0
Interrupt is disabled. In addition, PPKT and TXFT do not clear the EN-bit and the DMAC is not disabled.
INE = 1
Enables the EN interrupt. When this bit is set, the DMA interrupts the MCU on a 1 to 0 transition of the
EN bit. (When transfer is completed, EN = 0)
DMA channel enable bit. The MCU sets this bit to start the DMA transfer. When the transfer completes, or when it
is terminated due to error, this bit is cleared. The 1 to 0 transition of this bit generates an interrupt (if interrupt is
enabled).
EN = 0
DMA is halted. The DMA is halted when the byte count reaches zero or transaction time-out occurs. When
halted, the DMA updates the byte count, sets NAK = 0 in OEDB, and interrupts the MCU (if INE = 1).
EN = 1
Setting this bit starts the DMA transfer.
6.1.2
DMACSR1: DMA Control And Status Register (UART Transmit Channel) (Addr:FFE1)
This register is used to define the transaction time-out value. In addition, it contains a completion code that reports
any errors or a time-out condition.
7
6
5
4
3
2
1
0
TEN
C4
C3
C2
C1
C0
TXFT
PPKT
R/W
R/W
R/W
R/W
R/W
R/W
R/C
R/C
BIT
0
1
6–2
7
NAME
RESET
PPKT
TXFT
0
0
FUNCTION
Partial packet condition bit. This bit is set by the DMA and cleared by the MCU (see Table 6–2).
PPKT = 0
No partial-packet condition
PPKT = 1
Partial-packet condition detected. When IEN = 0, this bit does not clear the EN bit in DMACDR;
therefore, the DMAC stays enabled, ready for the next transaction. Clears when MCU writes a 1.
Writing a 0 has no effect.
Transfer time-out condition (see Table 6–2)
TXFT = 0
DMA stopped transfer without time-out
TXFT = 1
DMA stopped due to transaction time-out. When IEN = 0, this bit does not clear the EN bit in
DMACDR; therefore, the DMAC stays enabled, ready for the next transaction. DMA clears when
the MCU writes a 1. Writing a 0 has no effect.
C[4:0]
0
This field is used to define the transaction time-out value in 1-ms increments. This value is loaded to a down
counter every time a byte transfer occurs. The down counter is decremented every SOF pulse (1 ms). If the
counter decrements to zero it sets TXFT = 1 (in DMACSR register) and halts the DMA transfer. The counter starts
counting only when TEN = 1 and EN = 1 (in DMACDR) and the first byte has been transmitted (see Figure 6–1).
00000 = 0-ms time-out
:
:
11111 = 31-ms time-out
TEN
0
Transaction time-out counter enable/disable bit.
TEN = 0
TEN = 1
Counter is disabled (does not time-out)
Counter is enabled
Table 6–2. DMA OUT-Termination Condition
OUT TERMINATION
TXFT
PPKT
COMMENTS
UART partial packet
0
1
This condition occurs when the host sends a partial packet.
UART time-out
1
0
This condition occurs when X- and Y-output buffers are full and the UART transmitter cannot
transmit (due to flow-control restriction) or if host has no data to transmit.
C[4:0]
SOF
TEN
EN
Counter
Load
TXFT
Figure 6–1. Transaction Time-Out Diagram
6–3
6.1.3
DMACDR3: DMA Channel Definition Register (UART Receive Channel) (Addr:FFE4)
These registers are used to define the EDB number that the DMA uses for data transfer from the UARTS. In addition,
these registers define the data transfer direction and selects X or Y as the transaction buffer.
7
6
5
4
3
2
1
0
EN
INE
CNT
XY
T/R
E2
E1
E0
R/W
R/W
R/W
R/W
R/O
R/W
R/W
R/W
BIT
2–0
NAME
RESET
FUNCTION
E[2:0]
0
Endpoint descriptor pointer. This field points to a set of EDB registers that are used for a given transfer.
3
T/R
1
This bit is always 1. This indicates that the DMA data transfer is from UART RDR register to SRAM.
(The MCU cannot change this bit.)
4
XY
0
XY Buffer select bit. Valid only when CNT = 0.
XY = 0
XY = 1
5
6
7
6–4
CNT
INE
EN
0
0
0
Next buffer to transmit/receive is X
Next buffer to transmit/receive is Y
DMA continuous transfer control bit. This bit defines the mode of the DMA transfer.
CNT = 0
Burst mode: DMA stops the transfer when the byte count = 0 or when a receiver error occurs.
At the end of transfer, the high-to-low transition of EN interrupts the MCU (if enabled). In this
mode, the XY bit is set by the MCU to define the current buffer (X or Y).
CNT = 1
Continuous mode: In this mode, the DMA and UBM alternate between the X- and Y-buffers.
The UBM sets the XY bit and the DMA uses it for the transfer. The DMA alternates between
the X-/Y-buffers and continues receiving (to X-/Y-buffer) without MCU intervention. The DMA
terminates the transfer and interrupts the MCU, under the following conditions:
1. Transaction time-out expired: DMA updates EDB and interrupts the MCU. UBM transfers
the partial packet to the host.
2. UART receiver error condition: DMA updates EDB and does not interrupt the MCU. UBM
transfers the partial packet to the host.
DMA interrupt enable/disable bit. This bit is used to enable/disable the interrupt on transfer completion.
INE = 0
Interrupt is disabled. In addition, OVRUN and TXFT do not clear the EN bit and the DMAX is
not disabled.
INE = 1
Enables the EN interrupt. When this bit is set, the DMA interrupts the MCU on a 1 to 0 transition
of the EN bit. (When transfer is completed, EN = 0).
DMA channel enable bit. The MCU sets this bit to start the DMA transfer. When transfer completes, or
when terminated due to error, this bit is cleared. The 1 to 0 transition of this bit generates an interrupt (if
interrupt is enabled).
EN = 0
DMA is halted. The DMA is halted when transaction time-out occurs, or under a UART
receiver-error condition. When halted, the DMA updates the byte count and sets NAK = 0 in
IEDB. If the termination is due to transaction time-out, the DMA generates an interrupt.
However, if the termination is due to a UART error condition, the DMA does not generate an
interrupt. (The UART generates the interrupt.)
EN = 1
Setting this bit starts the DMA transfer.
6.1.4
DMACSR3: DMA Control And Status Register (UART Receive Channel) (Addr:FFE5)
This register is used to define the transaction time-out value. In addition, it contains a completion code that reports
any errors or a time-out condition.
7
6
5
4
3
2
1
0
TEN
C4
C3
C2
C1
C0
TXFT
OVRUN
R/W
R/W
R/W
R/W
R/W
R/W
R/C
R/C
BIT
NAME
RESET
0
OVRUN
0
1
TXFT
6–2
7
0
C[4:0]
0
OVRUN = 0
No overrun condition
OVRUN = 1
Overrun condition detected. When IEN = 0, this bit does not clear the EN bit in DMACDR;
therefore, the DMAC stays enabled, ready for the next transaction. Clears when the MCU writes
a 1. Writing a 0 has no effect.
Transfer time-out condition bit (see Table 6–3)
00000b
TEN
FUNCTION
Overrun condition bit. This bit is set by DMA and cleared by the MCU (see Table 6–3)
TXFT = 0
DMA stopped transfer without time-out
TXFT =1
DMA stopped due to transaction time-out. When IEN = 0, this bit does not clear the EN bit in
DMACDR; therefore, the DMAC stays enabled, ready for the next transaction. Clears when the
MCU writes a 1. Writing a 0 has no effect.
This field is used to define the transaction time-out value in 1-ms increments. This value is loaded to a down
counter every time a byte transfer occurs. The down counter is decremented every SOF pulse (1 ms). If the
counter decrements to zero it sets TXFT = 1 (in DMACSR register) and halts the DMA transfer. The counter starts
counting only when TEN = 1 and EN = 1 (in DMACDR) and the first byte has been received (see Figure 6–1).
00000 = 0-ms time-out
:
:
11111 = 31-ms time-out
Transaction time-out counter enable/disable bit
TEN = 0
TEN = 1
Counter is disabled (does not time-out)
Counter is enabled
Table 6–3. DMA IN-Termination Condition
TXFT
OVRUN
UART error
IN TERMINATION
0
0
UART error condition detected
COMMENTS
UART partial packet
1
0
This condition occurs when UART receiver has no more data for the host (data
starvation).
UART overrun
1
1
This condition occurs when X- and Y-input buffers are full and the UART FIFO is full (host
is busy).
6.2 Bulk Data I/O Using the EDB
The UBM (USB buffer manager) and the DMAC (DMA controller) access the EDB to fetch buffer parameters for IN
and OUT transactions (IN and OUT are with respect to host). In this discussion, it is assumed that (a) the MCU
initialized the EDBs, (b) DMA-continuous mode is being used, (c) double buffering is being used, and (d) the X/Y
toggle is controlled by the UBM.
NOTE: The IN and OUT transfers apply to UART.
6.2.1
IN Transaction (TUSB3410 to Host)
1. The MCU initializes the IEDB (64-byte packet, and double buffering is used) and the following DMA
registers:
•
DMACSR: Defines the transaction time-out value.
•
DMACDR: Defines the IEDB being used and the DMA mode of operation (continuous mode). Once this
register is set with EN = 1, the transfer starts.
6–5
2. The DMA transfers data from the UART to the X buffer. When a block of 64 bytes is transferred, the DMA
updates the byte count and sets NAK = 0 in IEDB (indicating to the UBM that the X buffer is ready to be
transferred to host). The UBM starts X-buffer transfer to host using the byte-count value in IEDB and toggles
the X/Y bit. The DMA continues transferring data from a device to Y-buffer. At the end of the block transfer,
the DMA updates the byte count and sets NAK = 0 in IEDB (indicating to the UBM that the Y-buffer is ready
to be transferred to host). The DMA continues the transfer from the device to host, alternating between
X-and Y-buffers without MCU intervention.
3. Transfer termination: As mentioned, the DMA/UBM continues the data transfer, alternating between the Xand Y-buffers. Termination of the transfer can happen under the following conditions:
6.2.2
•
Stop Transfer: The host notifies the MCU (via control-end-point) to stop the transfer. Under this
condition, the MCU sets EN = 0 in the DMACDR register.
•
Partial Packet: The device receiver has no data to be transferred to host. Under this condition, the
byte-count value is less than 64 when the transaction timer time-out occurs. When the DMA detects this
condition, it sets TXFT = 1 and OVRUN = 0, updates the byte count and NAK bit (partial packet) in the
IEDB, and interrupts the MCU. UBM transfers the partial packet to host.
•
Buffer Overrun: The host is busy, X- and Y-buffers are full (X NAK = 0 and Y–NAK = 0) and the DMA
cannot write to these buffers. The transaction time-out stops the DMA transfer, the DMA sets TXFT = 1
and OVRUN = 1, and interrupts the MCU.
•
UART Error Condition: When receiving from a UART, a receiver-error condition stops the DMA and
sets TXFT = 1 and OVRUN = 0, but the EN bit remains set at 1. Therefore, the DMA does not interrupt
the MCU. However, the UART generates a status interrupt, notifying the MCU that an error condition
has occurred.
OUT Transaction (Host to TUSB3410)
1. The MCU initializes the OEDB (64-byte packet, and double buffering is used) and the following DMA
registers:
•
DMACSR: Defines the transaction time-out value.
•
DMACDR: Defines the OEDB being used, and the DMA mode of operation (continuous mode). Once
the EN bit is set to 1 in this register, the transfer starts.
2. The UBM transfers data from host to X-buffer. When a block of 64 bytes is transferred, the UBM updates
the byte count and sets NAK = 1 in OEDB (indicating to DMA that the X-buffer is ready to be transferred
to the UART). The DMA starts X-buffer transfer using the byte-count value in OEDB. The UBM continues
transferring data from host to Y-buffer. At the end of the block transfer, the UBM updates the byte count and
sets NAK = 1 in OEDB (indicating to DMA that the Y-buffer is ready to be transferred to device). The DMA
continues the transfer from the X-/Y-buffers to the device, alternating between X- and Y-buffers without MCU
intervention.
3. Transfer termination: The DMA/UBM continues the data transfer alternating between X- and Y-buffers. The
termination of the transfer can happen under the following conditions:
6–6
•
Stop Transfer: The host notifies the MCU (via control-end point) to stop the transfer. Under this
condition, the MCU sets EN = 0 in the DMACDR register.
•
Partial-Packet: UBM receives a partial packet from host. Under this condition, the byte-count value is
less than 64 and the transaction timer does not time-out. When the DMA detects this condition, it
transfers the partial packet to the device, sets TXFT = 0 and PPKT = 1, updates NAK = 0 in OEDB, and
interrupts the MCU.
•
Time-out: The device is busy, X- and Y-buffers are full (X-NAK = 1 and Y-NAK = 1) and the UBM cannot
write to these buffers. Under this condition the transaction timer time-out stops the DMA transfer, sets
TXFT = 1 and OVRUN = 0, and interrupts the MCU.
7 UART
7.1 UART Registers
Table 7–1 summarizes the UART registers. These registers are used for data I/O, control, and status information.
UART setup is done by the MCU. Data transfer is typically performed by the DMAC. However, the MCU can perform
data transfer without DMA; this is useful when debugging the firmware.
Table 7–1. UART Registers Summary
7.1.1
REGISTER NAME
ACCESS
RDR
R/O
UART receiver data register
FUNCTION
Can be accessed by MCU or DMA
COMMENTS
TDR
W/O
UART transmitter data register
Can be accessed by MCU or DMA
LCR
R/W
UART line control register
FCRL
R/W
UART flow control register
MCR
R/W
UART modem control register
LSR
R/O
UART line status register
Can generate an interrupt
MSR
R/O
UART modem status register
Can generate an interrupt
DLL
R/W
UART divisor register (low byte)
DLH
R/W
UART divisor register (high byte)
XON
R/W
UART Xon register
XOFF
R/W
UART Xoff register
MASK
R/W
UART interrupt mask register
Can control three interrupt sources
RDR: Receiver Data Register (Addr:FFA0)
The receiver data register consists of a 32-byte FIFO. Data received from the SIN pin are converted from
serial-to-parallel format and stored in this FIFO. Data transfer from this register to the RAM buffer is the responsibility
of the DMA controller.
7
6
5
4
3
2
1
0
D7
D6
D5
D4
D3
D2
D1
D0
R/O
R/O
R/O
R/O
R/O
R/O
R/O
R/O
BIT
NAME
7–0
RESET
D[7:0]
7.1.2
FUNCTION
0
Receiver byte
TDR: Transmitter Data Register (Addr:FFA1)
The transmitter data register is double buffered. Data written to this register is loaded into the shift register, and shifted
out on SOUT. Data transfer from the RAM buffer to this register is the responsibility of the DMA controller.
7
6
5
4
3
2
1
0
D7
D6
D5
D4
D3
D2
D1
D0
W/O
W/O
W/O
W/O
W/O
W/O
W/O
W/O
BIT
7–0
NAME
D[7:0]
RESET
0
FUNCTION
Transmit byte
7–1
7.1.3
LCR: Line Control Register (Addr:FFA2)
This register controls the data communication format. The word length, number of stop bits, and parity type are
selected by writing the appropriate bits to the LCR.
7
6
5
4
3
2
1
0
FEN
BRK
FPTY
EPRTY
PRTY
STP
WL1
WL0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
BIT
NAME
RESET
1:0
WL{1–0]
0
Specifies the word length for transmit and receive
00b = 5 bits
01b = 6 bits
10b = 7 bits
11b = 8 bits
STP
0
Specifies the number of stop bits for transmit and receive
2
FUNCTION
STP = 0
STP = 1
STP = 1
3
PRTY
0
Specifies whether parity is used
PRTY = 0
PRTY = 1
4
EPRTY
0
FPTY
0
BRK
0
FEN
0
Normal operation
Forces SOUT into break condition (logic 0)
FIFO enable. This bit is used to disable/enable the FIFO. To reset the FIFO, the MCU clears and then sets
this bit.
FEN = 0
FEN = 1
7–2
Parity is not forced
Parity bit is forced. If [EPRTY = 0], the parity bit is forced to 1
This bit is the break-control bit
BRK = 0
BRK = 1
7
Odd parity is generated (if PRTY = 1)
Even parity is generated (if PRTY = 1)
Selects the forced parity bit
FPTY = 0
FPTY = 1
6
No parity
Parity is generated
Specifies whether even or odd parity is generated
EPRTY = 0
EPRTY = 1
5
1 stop bit (word length = 5, 6, 7, 8)
1.5 stop bits (word length = 5)
2 stop bits (word length = 6, 7, 8)
The FIFO is cleared and disabled. When disabled the selected receiver flow control is activated.
The FIFO is enabled and it can receive data.
7.1.4
FCRL: UART Flow Control Register (Addr:FFA3)
This register provides the flow-control modes of operation (see Table 7–3 for more details).
7
6
5
4
3
2
1
0
485E
DTR
RTS
RXOF
DSR
CTS
TXOA
TXOF
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
BIT
0
NAME
TXOF
RESET
0
FUNCTION
This bit controls the transmitter Xon/Xoff flow control.
TXOF = 0
TXOF = 1
1
TXOA
0
This bit controls the transmitter Xon-on-any/Xoff flow control
TXOA = 0
TXOA = 1
2
CTS
0
DSR
0
RXOF
0
RTS
0
DTR
0
485E
0
Disables receiver RTS flow control
Receiver RTS flow control is enabled. RTS output pin goes high when the receiver FIFO HALT
trigger level is reached; it goes low, when the receiver FIFO RESUME receiving trigger level is
reached.
Receiver DTR flow-control enable bit
DTR = 0
DTR = 1
7
Receiver does not attempt to match Xon/Xoff characters
Receiver searches for Xon/Xoff characters
Receiver RTS flow control enable bit
RTS = 0
RTS = 1
6
Disables transmitter DSR flow control
DSR flow control is enabled, i.e., when DSR input pin is high, transmission is halted; when the DSR
pin is low, transmission resumes.
This bit controls the receiver Xon/Xoff flow control.
RXOF = 0
RXOF = 1
5
Disables transmitter CTS flow control
CTS flow control is enabled, i.e., when CTS input pin is high, transmission is halted; when the CTS
pin is low, transmission resumes.
Transmitter DSR flow-control enable bit
DSR = 0
DSR = 1
4
Disable the transmitter Xon-on-any/Xoff flow control
Enable the transmitter Xon-on-any/Xoff flow control
Transmitter CTS flow-control enable bit
CTS = 0
CTS = 1
3
Disable transmitter Xon/Xoff flow control
Enable transmitter Xon/Xoff flow control
Disables receiver DTR flow control
Receiver DTR flow control is enabled. DTR output pin goes high when the receiver FIFO HALT
trigger level is reached; it goes low, when the receiver FIFO RESUME receiving trigger level is
reached.
RS485 enable bit. This bit is used to configure the UART to control external RS485 transceivers. When
configured in half-duplex mode (485E=1), RTS or DTR can be used to enable the RS485 driver or receiver.
See Figure 5.
485E = 0
485E = 1
UART is in normal operation mode (full duplex)
The UART is in half duplex RS485 mode. In this mode RTS and DTR are active with opposite
polarity (when RTS = 0, DTR = 1). When the DMA is ready to transmit, it drives RTS = 1 (and
DTR = 0) 2–bit–time before transmission starts. When DMA terminates the transmission, it drives
RTS = 0 (and DTR = 1) after transmission stops. When 485E is set to 1, the DTR and RTS bits in
the MCR register have no effect. Also, see the RCVE bit in MCR: modem-control register.
7–3
7.1.5
Transmitter Flow Control
On reset (power up, USB or soft reset) the transmitter defaults to the Xon state and the flow control is set to mode–0
(flow control is disabled).
Table 7–2. Transmitter Flow-Control Modes
MODE
3
2
1
0
DSR
CTS
TXOA
TXOF
0
All flow control is disabled
0
0
0
0
1
Xon/Xoff flow control is enabled
0
0
0
1
2
Xon on any/ Xoff flow control
0
0
1
0
3
Not permissible (see Note 1)
X
X
1
1
4
CTS flow control
0
1
0
0
5
Combination flow control (see Note 2)
0
1
0
1
6
Combination flow control
0
1
1
0
7
DSR flow control
1
0
0
0
9-E
Combination flow control
NOTES: 1. This is a nonpermissible combination. If used, TXOA and TXOF are cleared.
2. Combination example: Transmitter stops when either CTS or Xoff is detected. Transmitter resumes when both CTS is negated and
Xon is detected.
Table 7–3. Receiver Flow-Control Possibilities
MODE
6
5
4
DTR
RTS
RXOF
0
All flow control is disabled
0
0
0
1
Xon/Xoff flow control is enabled
0
0
1
2
RTS flow control
0
1
0
3
Combination flow control (see Note 3)
0
1
1
4
DTR flow control
1
0
0
5
Combination flow control
1
0
1
6
Combination flow control (see Note 4)
1
1
0
7
Combination flow control
1
1
1
NOTES: 3. Combination example: Both RTS is asserted and Xoff transmitted when FIFO is full. Both RTS is deasserted and Xon is transmitted
when FIFO is empty.
4. Combination example: Both DTR and RTS are asserted when FIFO is full. Both DTR and RTS are deasserted when FIFO is empty.
7–4
7.1.6
MCR: Modem-Control Register (Addr:FFA4)
This register provides control for modem interface I/O and definition of the flow control mode.
7
6
5
4
3
2
1
0
LCD
LRI
RTS
DTR
SEN
LOOP
RCVE
URST
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
BIT
0
1
2
NAME
URST
RCVE
LOOP
RESET
0
0
0
FUNCTION
Uart soft reset. This bit can be used by the MCU to reset the UART.
URST = 0
Normal operation. Writing a 0 by MCU has no effect.
URST = 1
When the MCU writes a 1 to this bit, a UART reset is generated (ORed with hard reset). When
the UART exits the reset state, URST is cleared. The MCU can monitor this bit to determine if the
UART completed the reset cycle.
Receiver enable bit. This bit is valid only when 485E in FCRL is 1 (RS485 mode). When 485E = 0, this bit has
no effect on the receiver.
RCVE = 0
When 485E = 1, the UART receiver is disabled when RTS = 1, i.e., when data is being transmitted,
the UART receiver is disabled.
RCVE = 1
When 485E = 1, the UART receiver is enabled regardless of the RTS state, i.e., UART receiver
is enabled all the time. This mode can be used to detect collisions on the RS-485 bus when
received data does not match transmitted data.
This bit controls the normal-/loop-back mode of operation (see Figure 7–1).
LOOP = 0
Normal operation
LOOP = 1
Enable loop-back mode of operation. In this mode the following occur:
S
SOUT is set high
S
SIN is disconnected from the receiver input.
S
The transmitter serial output is looped back into the receiver serial input.
S
The four modem-control inputs: CTS, DSR, DCD, and RI are disconnected.
S
DTR, RTS, LRI and LCD are internally connected to the four modem-control inputs, and read
in the MSR register as follows:
S DTR is reflected in MSR[4] bit
S RTS is reflected in MSR[5] bit
S LRI is reflected in MSR[6] bit
S LCD is reflected in MSR[7] bit
3
RSV
0
Reserved
4
DTR
0
This bit controls the state of the DTR output pin (see Figure 7–1). This bit has no effect when auto-flow control
is used or when 485E = 1 (in FCRL register).
5
RTS
0
DTR = 0
Forces the DTR output pin to inactive (high)
DTR = 1
Forces the DTR output pin to active (low)
This bit controls the state of the RTS output pin (see Figure 7–1). This bit has no effect when auto-flow control
is used or when 485E = 1 (in FCRL register).
RTS = 0
Forces the RTS output pin to inactive (high)
RTS = 1
Forces the RTS output pin to active (low)
7–5
LRI
6
7
0
LCD
7.1.7
0
This bit is used for loop-back mode only. When in loop-back mode, this bit is reflected in MSR[6]-bit (see
Figure 7–1).
LRI = 0
Clears MSR[6] = 0
LRI = 1
Sets MSR[6] = 1
This bit is used for loop-back mode only. When in loop-back mode, this bit is reflected in MSR[7]-bit (see
Figure 7–1).
LCD = 0
Clears MSR[7] = 0
LCD = 1
Sets MSR[7] = 1
LSR: Line-status Register (Addr:FFA5)
This register provides the status of the data transfer. DMA transfer is halted when any of OVR, PTE, FRE, BRK, or
EXIT is 1.
7
6
5
4
3
2
1
0
RSV
TEMT
TxE
RxF
BRK
FRE
PTE
OVR
R/O
R/O
R/O
R/O
R/C
R/C
R/C
R/C
BIT
0
NAME
OVR
RESET
0
FUNCTION
This bit indicates the overrun condition of the receiver. If set, it halts the DMA transfer and generates a
status interrupt (if enabled).
OVR = 0
OVR = 1
1
PTE
0
This bit indicates the parity condition of the received byte. If set, it halts the DMA transfer and generates a
status interrupt (if enabled).
PTE = 0
PTE = 1
2
FRE
0
BRK
0
RxF
0
TxE
1
TEMT
1
7–6
RSV
0
TDR is not empty
TDR is empty. Generates Tx interrupt (if enabled).
This bit indicates the condition of both transmitter data register and shift register is empty.
TEMT = 0
TEMT = 1
7
No data in the RDR
RDR contains data. Generates Rx interrupt (if enabled).
This bit indicates the condition of the transmitter data register. Typically, the MCU does not monitor this bit
since data transfer is done by the DMA controller.
TxE = 0
TxE = 1
6
No break condition
A break condition in data received was detected. Clears when the MCU writes a 1. Writing a 0
has no effect.
This bit indicates the condition of the receiver data register. Typically, the MCU does not monitor this bit
since data transfer is done by the DMA controller.
RxF = 0
RxF = 1
5
No framing error in data received
Framing error in data received. Clears when MCU writes a 1. Writing a 0 has no effect.
This bit indicates the break condition of the received byte. If set, it halts the DMA transfer and generates a
status interrupt (if enabled).
BRK = 0
BRK = 1
4
No parity error in data received
Parity error in data received. Clears when the MCU writes a 1. Writing a 0 has no effect.
This bit indicates the framing condition of the received byte. If set, it halts the DMA transfer and generates
a status interrupt (if enabled).
FRE = 0
FRE = 1
3
No overrun error
Overrun error has occurred. Clears when the MCU writes a 1. Writing a 0 has no effect.
Either TDR or TSR is not empty
Both TDR and TSR are empty
Reserved = 0
CTS
DSR
MSR
(4) LCTS
RI
(5) LDSR
DCD
(6) LRI
(7) LCD
MCR
(4) DTR
DTR
(5) RTS
RTS
(6) LRI
(7) LCD
(2) LOOP
Figure 7–1. MSR and MCR Registers in Loop-Back Mode
7.1.8
MSR: Modem-Status Register (Addr:FFA6)
This register provides information about the current state of the control lines from the modem.
7
6
5
4
3
2
1
0
LCD
LRI
LDSR
LCTS
∆CD
TRI
∆DSR
∆CTS
R/O
R/O
R/O
R/O
R/C
R/C
R/C
R/C
BIT
0
NAME
∆CTS
RESET
0
FUNCTION
This bit indicates that the CTS input has changed state. Cleared when the MCU writes a 1 to this bit.
Writing a 0 has no effect.
∆CTS = 0
∆CTS = 1
1
∆DSR
0
This bit indicates that the DSR input has changed state. Cleared when the MCU writes a 1 to this bit.
Writing a 0 has no effect.
∆DSR = 0
∆DSR = 1
2
TRI
0
∆CD
0
LCTS
0
LDSR
0
LRI
0
CTS input is high
CTS input is low
During loop back, this bit reflects the status of MCR[0] (see Figure 7–1).
LDSR = 0
LDSR= 1
6
Indicates no change in the CD input
Indicates that the CD input has changed state since the last time it was read.
During loopback, this bit reflects the status of MCR[1] (see Figure 7–1)
LCTS = 0
LCTS = 1
5
Indicates no applicable transition on the RI input
Indicates that an applicable transition has occurred on the RI input.
This bit indicates that the CD input has changed state. Cleared when the MCU writes a 1 to this bit. Writing
a 0 has no effect.
∆CD = 0
∆CD = 1
4
Indicates no change in the DSR input
Indicates that the DSR input has changed state since the last time it was read. Clears when the
MCU writes a 1. Writing a 0 has no effect.
Trailing edge of the ring indicator. This bit indicates that the RI input has changed from low to high. This bit
is cleared when the MCU writes a 1 to this bit. Writing a 0 has no effect.
TRI = 0
TRI = 1
3
Indicates no change in the CTS input
Indicates that the CTS input has changed state since the last time it was read. Clears when the
MCU writes a 1. Writing a 0 has no effect.
DSR input is high
DSR input is low
During loop back, this bit reflects the status of MCR[2] (see Figure 7–1).
LRI = 0
LRI = 1
RI input is high
RI input is low
7–7
BIT
NAME
7
RESET
LCD
0
FUNCTION
During loopback, this bit reflects the status of MCR[3] (see Figure 7–1).
LCD = 0
LCD = 0
7.1.9
CD input is high
CD input is low
DLL: Divisor Register Low Byte (Addr:FFA7)
This register contains the low byte of the baud-rate divisor.
7
6
5
4
3
2
1
0
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
BIT
NAME
7–0
RESET
D[7:0]
08h
FUNCTION
Low-byte value of the 16-bit divisor for generation of the baud clock in the baud-rate generator.
7.1.10 DLH: Divisor Register High Byte (Addr:FFA8)
This register contains the high byte of the baud-rate divisor.
7
6
5
4
3
2
1
0
D15
D14
D13
D12
D11
D10
D9
D8
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
BIT
7–0
NAME
D[15:8]
RESET
00h
FUNCTION
High-byte value of the 16-bit divisor for generation of the baud clock in the baud-rate generator.
7.1.11 Baud-rate Calculation
The following formulas are used to calculate the baud-rate clock and the divisors. The baud-rate clock is derived from
the 96-MHz master clock (dividing by 6.5). The table below presents the divisors used to achieve the desired baud
rates, together with the associate rounding errors.
Baud CLK + 96 MHz + 14.76923077 MHz
6.5
Divisor + 14.76923077
Baud Rate
7–8
10 6
16
Table 7–4. DLL/DLH Values and Resulted Baud Rates
DLL/DLH VALUE
DESIRED BAUD
ACTUAL BAUD
ERROR %
DEC.
HEX.
1 200
769
0301
1 200.36
0.03
2 400
385
0181
2 397.60
0.01
4 800
192
00C0
4 807.69
0.16
7 200
128
0080
7 211.54
0.16
9 600
96
0060
9 615.38
0.16
14 400
64
0040
14 423.08
0.16
19 200
48
0030
19 230.77
0.16
38 400
24
0018
38 461.54
0.16
57 600
16
0010
57 692.31
0.16
115 200
8
0008
115 384.62
0.16
230 400
4
0004
230 769.23
0.16
460 800
2
0002
461 538.46
0.16
921 600
1
0001
923 076.92
0.16
NOTE: The TUSB3410 does support baud rates lower than 1200 bps, which are not
listed due to less interest.
7.1.12 XON: Xon Register (Addr:FFA9)
This register contains a value that is compared to the received data stream. Detection of a match interrupts the MCU
(only if the interrupt enable bit is set). This value is also used for Xon transmission.
7
6
5
4
3
2
1
0
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
BIT
NAME
7–0
RESET
D[7:0]
0000
FUNCTION
Xon value to be compared to the incoming data stream
7.1.13 XOFF: Xoff Register (Addr:FFAA)
This register contains a value that is compared to the received data stream. Detection of a match halts the DMA
transfer, and interrupts the MCU (only if the interrupt enable bit is set). This value is also used for Xoff transmission.
7
6
5
4
3
2
1
0
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
BIT
7–0
NAME
D[7:0]
RESET
0000
FUNCTION
Xoff value to be compared to the incoming data stream
7–9
7.1.14 MASK: UART Interrupt-Mask Register (Addr:FFAB)
This register controls the UARTs interrupt sources.
7
6
5
4
3
2
1
0
RSV
RSV
RSV
RSV
RSV
RRIE
SIE
MIE
R/O
R/O
R/O
R/O
R/O
R/W
R/W
R/W
BIT
0
NAME
MIE
RESET
0
FUNCTION
This bit controls the UART-modem interrupt.
MIE = 0
MIE = 1
1
SIE
0
This bit controls the UART-status interrupt.
SIE = 0
MIE = 1
2
TRI
0
RSV
0
Status interrupt is disabled
Status interrupt is enabled
This bit controls the UART-TxE/RxF interrupts
TRIE = 0
TRIE = 1
7–3
Modem interrupt is disabled
Modem interrupt is enabled
TxE/RxF interrupts are disabled
TxE/RxF interrupts are enable
Reserved = 0
7.2 UART Data Transfer
Figure 7–2 illustrates the data transfer between the UART and the host using the DMA controller and the USB buffer
manager (UBM). A buffer of 512 bytes is reserved for buffering the UART channel (transmit and receive buffers). The
UART channel has 64 bytes of double-buffer space (X- and Y-buffer). When the DMA writes to the X-buffer, the UBM
reads from the Y-buffer. Similarly, when the DMA reads from the X-buffer, the UBM writes to the Y-buffer. The DMA
channel is configured to operate in the continuous mode (by setting DMACDR[CNT] = 1). Once the MCU enables
the DMA, data transfer toggles between the UMB and the DMA without MCU intervention. See IN transaction
(TUSB3410 to host) for DMA transfer-termination condition.
7.2.1
Receiver Data Flow
The UART receiver has a 32-byte FIFO. The receiver FIFO has two trigger levels. One is the high-level mark (HALT),
which is set to 28 bytes, and the other is the low-level mark (RESUME), which is set to 4 bytes. When the HALT mark
is reached, either the RTS pin goes high or Xoff is transmitted (depending on the auto setting). When the FIFO
reaches the RESUME mark, then either the RTS pin goes low or Xon is transmitted.
7–10
Receiver
Halt on Error or Time-Out
64-Byte
Y-Buffer
RDR: 32-Byte FIFO
DMA
DMACDR
4
8
SIN
64-Byte
X-Buffer
RTS/DTR = 1
or Xoff Transmitted
X/Y
Host
RTS/DTR = 0
or Xon Transmitted
UBM
Xoff/Xon
CTS/DTR = 1/0
64-Byte
Y-Buffer
Pause/Run
DMA
DMACDR
64-Byte
X-Buffer
SOUT
TDR
Figure 7–2. Receiver/Transmitter Data Flow
7.2.2
Hardware Flow Control
Figure 7–3 illustrates the connection necessary to achieve hardware flow control. The CTS and RTS signals are
provided for this purpose. Auto CTS and auto RTS (and Xon/Xoff) can be enabled/disabled independently by
programming the FCRL register.
TUSB3410
SIN
RTS
SOUT
CTS
External Device
SOUT
CTS
SIN
RTS
Figure 7–3. Auto Flow Control Interconnect
7.2.3
Auto RTS (Receiver Control)
In this mode, the RTS output pin signals the receiver-FIFO status to an external device. The RTS output signal is
controlled by the high- and low-level marks of the FIFO. When the high-level mark is reached, RTS goes high,
signaling to an external sending device to halt its transfer. Conversely, when the low-level mark is reached, RTS goes
low, signaling to an external sending device to resume its transfer.
Data transfer from the FIFO to the X-/Y-buffer is performed by the DMA controller. See OUT transaction (TUSB3410
to host) for DMA transfer-termination condition.
7.2.4
Auto CTS (Transmitter Control)
In this mode, the CTS input pin controls the transfer from internal buffer (X or Y) to the TDR. When the DMA controller
transfers data from the Y-buffer to the TDR and the CTS input pin goes high, the DMA controller is suspended until
CTS goes low. Meanwhile, the UBM is transferring data from the host to the X-buffer. When CTS goes low, the DMA
resumes the transfer. Data transfer continues alternating between the X- and Y-buffers, without MCU intervention.
See OUT transaction (TUSB3410 to host) for DMA transfer-termination condition.
7–11
7.2.5
Xon/Xoff Receiver Flow Control
To enable Xon/Xoff flow control, certain MCR bits must be set as follows: MCR[5] = 1 and MCR[7:6] = 0. In this mode,
the Xon/Xoff bytes are transmitted to an external sending device to control the device’s transmission. When the
high-level mark (of the FIFO) is reached, the Xoff byte is transmitted, signaling to an external sending device to halt
its transfer. Conversely, when the low-level mark is reached, the Xon byte is transmitted, signaling to an external
sending device to resume its transfer. The data transfer from the FIFO to X-/Y-buffer is performed by the DMA
controller.
7.2.6
Xon/Xoff Transmit Flow Control
To enable Xon/Xoff flow control, certain MCR bits must be set as follows: MCR[5] = 1 and MCR[7:6] = 0. In this mode,
the incoming data are compared to the XON and XOFF registers. If a match to XOFF is detected, the DMA is paused.
If a match to XON is detected, the DMA resumes. Meanwhile, the UBM is transferring data from the host to the
X-buffer. The MCU does not switch the buffers unless the Y-buffer is empty and the X-buffer is full. When Xon is
detected, the DMA resumes the transfer.
7–12
8 Expanded GPIO Port
8.1 Input/Output and Control Registers
The TUSB3410 has four general-purpose I/O pins (P3.0, P3.1, P3.3, P3.4) that are controlled by firmware running
on the MCU. Each pin can be controlled individually and each is implemented with a 12-mA push/pull Cmos output
with tristate control plus input. The MCU treats the outputs as open drain types in that the output can be driven low
continuously, but a high output is driven for two clock cycles and then the output is tristated.
An input pin can be read using the MOV instruction. For example, MOV C,P3.3 reads the input on P3.3. As a
precaution, be certain the associated output is tristated before reading the input.
An output can be set high (and then tristated) using the SETB instruction. For example, SETB P3.1 sets P3.1 high.
An output can be set low using the CLR instruction, as in CLR P3.4, which sets P3.4 low (driven continuously until
changed).
Each GPIO pin has an associated internal pullup resistor. It is strongly recommended that the pullup resistor remain
connected to the pin to prevent oscillations in the input buffer. The only exception is if an external source always drives
the input.
8.1.1
PUR_3: GPIO Pullup Register For Port 3 (Addr:FF9E)
7
6
5
4
3
2
1
0
RSV
RSV
RSV
RSV
Pin3
RSV
Pin1
Pin0
R/O
R/O
R/O
R/W
R/W
R/O
R/W
R/W
BIT
NAME
RESET
FUNCTION
0–7
Pin N
(N = 0 to 7)
0
The MCU may write to this register. If the MCU sets this bit to 1, the pullup resistor is disconnected from
the pin. If the MCU clears this bit to 0, the pullup resistor is connected to the pin. The pullup resistor is
connected to the VCC power supply.
8–1
8–2
9 Interrupts
9.1 8052 Interrupt and Status Registers
All 8052 standard, five interrupt sources are preserved. SIE is the standard interrupt-enable register that controls the
five interrupt sources. All the additional interrupt sources are ORed together to generate EX0. The XINTO signal is
provided to interrupt an external MCU (see Figure 9–1).
Table 9–1. 8052 Interrupt Location Map
INTERRUPT SOURCE
DESCRIPTION
START ADDRESS
ES
UART interrupt
0023H
ET1
Timer-1 interrupt
001BH
EX1
External interrupt-1
0013H
ET0
Timer-0 interrupt
000BH
EX0
External interrupt-0
0003H
Reset
9.1.1
COMMENTS
Used for all internal peripherals
0000H
8052 Standard Interrupt Enable (SIE) Register
7
6
5
4
3
2
1
0
EA
X
X
ES
ET1
EX1
ET0
EX0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
BIT
NAME
RESET
FUNCTION
0
EX0
0
Enable or disable external interrupt-0
EX0 = 1 External interrupt-0 is disabled
EX0 = 1 External interrupt-0 is enabled
1
ET0
0
Enable or disable timer-0 interrupt
ET0 = 0
Timer-0 interrupt is disabled
ET0 = 1
Timer-0 interrupt is enabled
2
EX1
0
Enable or disable external interrupt-1
EX1 = 0 External interrupt-1 is disabled
EX1 = 1 External interrupt-1 is enabled
3
ET1
0
Enable or disable timer-1 interrupt
ET1 = 0
Timer-1 interrupt is disabled
EX1 = 1 Timer-1 interrupt is enabled
4
ES
0
Enable or disable serial port interrupts
ES = 0
Serial-port interrupt is disabled
ES = 1
Serial-port interrupt is enabled
RSV
EA
0
0
Reserved
Enable or disable all interrupts (global disable)
5, 6
7
EA = 0
EA = 1
9.1.2
Disable all interrupts
Each interrupt source is individually controlled
Additional Interrupt Sources
All nonstandard 8052 interrupts (DMA, I2C, etc.) are ORed to generate an internal INT0. Note, the external INT0 is
not used. Furthermore, the INT0 must be programmed as an active low-level interrupt (not edge triggered). A vector
interrupt register is provided to identify all interrupt sources (see VECINT: vector-interrupt register). Up to 64 interrupt
vectors are provided. It is the responsibility of the MCU to read the vector and dispatch to the proper interrupt routine.
9–1
9.1.3
VECINT: Vector Interrupt Register (Addr:FF92)
This register contains a vector value, which identifies the internal interrupt source that trapped to location 0003H.
Writing (any value) to this register removes the vector and updates the next vector value (if another interrupt is
pending). Note: the vector value is offset; therefore, its value is in increments of two (bit 0 is set to 0). When no interrupt
is pending, the vector is set to 00h (see Table 9–2). As shown, the interrupt vector is divided to two fields: I[2:0] and
G[3:0]. The I field defines the interrupt source within a group (on a first-come-first-served basis). In the G field, which
defines the group number, group G0 is the lowest, and G15 is the highest priority.
7
6
5
4
3
2
1
G3
G2
G1
G0
I2
I1
I0
0
R/O
R/O
R/O
R/O
R/O
R/O
R/O
R/O
BIT
NAME
RESET
FUNCTION
3–1
I[2:0]
0H
This field defines the interrupt source in a given group. See Table 9–2. Bit 0 = 0 always; therefore, vector values
are offset by two.
7–4
G[3:0]
0H
This field defines the interrupt group. I[2:0] and G[3:0] combine to produce the actual interrupt vector.
Table 9–2. Vector Interrupt Values
9–2
0
G[3:0]
I[2:0]
VECTOR
(Hex)
(Hex)
(Hex)
0
0
00
No interrupt
1
0
10
Not used
1
1
1
1
2
3
12
14
16
Output endpoint-1
Output endpoint-2
Output endpoint-3
2
0
20
Not used
2
2
2
3
3
3
3
3
3
3
3
1
2
3
0
1
2
3
4
5
6
7
22
24
26
30
32
34
36
38
3A
3C
3E
4
4
4
4
0
1
2
3
40
42
44
46
Input endpoint-1
Input endpoint-2
Input endpoint-3
STPOW packet received
SETUP packet received
RESERVED
RESERVED
RESR interrupt
SUSR interrupt
RSTR interrupt
Reserved
I2C TXE interrupt
I2C RXF interrupt
Input endpoint-0
Output endpoint-0
4
4–7
48 → 4E
Not used
5
5
5
0
1
4–7
50
52
58 → 5E
UART status interrupt
UART modem interrupt
Not used
6
6
6
7
0
1
4–7
5–7
60
62
68 → 6E
70 → 7E
UART RXF interrupt
UART TXE interrupt
Not used
Not used
8
8
8
0
2
5–7
80
84
88–8E
9–15
X
90 → FE
INTERRUPT SOURCE
DMA1 interrupt
DMA3 interrupt
Not used
Not used
9.1.4
Logical Interrupt Connection Diagram (Internal/External)
Figure 9–1 shows the logical connection of the interrupt sources and its relation with XINTO. The priority encoder
generates an 8-bit vector, corresponding to 64 interrupt sources (not all are used). The interrupt priorities are hard
wired. Vector 0x88 is the highest and 0x12 is the lowest.
Interrupts
Priority
Encoder
IEO
XINTO
Vector
IEO (INT0)
Figure 9–1. Internal Vector Interrupt
9–3
9–4
10 I2C-Port
10.1 I2C Registers
10.1.1 I2CSTA: I2C Status and Control Register (Addr:FFF0)
This register is used to control the stop condition for read and write operations. In addition, it provides transmitter and
receiver handshake signals with their respective interrupt enable bits.
7
6
5
4
3
2
1
0
RXF
RIE
ERR
1/4
TXE
TIE
SRD
SWR
R/O
R/W
R/C
R/W
R/O
R/W
R/W
R/W
BIT
NAME
RESET
FUNCTION
0
SWR
0
Stop write condition. This bit determines if the I2C controller generates a stop condition when data
from the I2CDAO register is transmitted to an external device.
1
2
SRD
TIE
0
0
SWR = 0
Stop condition is not generated when data from the I2CDAO register is shifted out to an
external device.
SWR = 1
Stop condition is generated when data from the I2CDAO register is shifted out to an
external device.
Stop read condition. This bit determines if the I2C controller generates a stop condition when data is
received and loaded into the I2CDAI register.
SRD = 0
Stop condition is not generated when data from the SDA line is shifted into the I2CDAI
register.
SRD = 1
Stop condition is generated when data from the SDA line are shifted into the I2CDAI
register.
I2C transmitter empty interrupt enable
TIE = 0
TIE = 1
3
4
TXE
1/4
1
0
I2C transmitter empty. This bit indicates that data can be written to the transmitter. It can be used for
polling or it can generate an interrupt.
TXE = 0
Transmitter is full. This bit is cleared when the MCU writes a byte to the II2CDAO
register.
TXE = 1
Transmitter is empty. The I2C controller sets this bit when the contents of the I2CDAO
register are copied to the SDA shift register.
Bus speed selection
1/4 = 0
1/4 = 1
5
6
ERR
RIE
0
0
RXF
0
100-kHz bus speed
400-kHz bus speed
Bus error condition. This bit is set by the hardware when the device does not respond. It is cleared by
the MCU.
ERR = 0
No bus error
ERR = 1
Bus error condition has been detected. Clears when the MCU writes a 1. Writing a 0 has
no effect.
I2C receiver ready interrupt enable
RIE = 0
RIE = 1
7
Interrupt disable
Interrupt enable
Interrupt disable
Interrupt enable
I2C receiver full. This bit indicates that the receiver contains new data. It can be used for polling or it
can generate an interrupt.
RXF = 0
RXF = 1
Receiver is empty. This bit is cleared when the MCU reads the I2CDAI register.
Receiver contains new data. This bit is set by the I2C controller when the received serial
data has been loaded into the I2CDAI register.
10–1
10.1.2 I2CADR: I2C Address Register (Addr:FFF3)
This register holds the device address and the read/write command bit.
7
6
5
4
3
2
1
0
A6
A5
A4
A3
A2
A1
A0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
BIT
NAME
0
RESET
R/W
0
FUNCTION
Read/write command bit
R/W = 0
R/W = 1
7–1
A[6:0]
0h
Write operation
Read operation
Seven address bits for device addressing
10.1.3 I2CDAI: I2C Data-Input Register (Addr:FFF2)
This register holds the received data from an external device.
7
6
5
4
3
2
1
0
D7
D6
D5
D4
D3
D2
D1
D0
R/O
R/O
R/O
R/O
R/O
R/O
R/O
R/O
BIT
NAME
7–0
RESET
D[7:0]
FUNCTION
8-bit input data from an I2C device
0
10.1.4 I2CDAO: I2C Data-Output Register (Addr:FFF1)
This register holds the data to be transmitted to an external device. Writing to this register starts the transfer on the
SDA line.
7
6
5
4
3
2
1
0
D7
D6
D5
D4
D3
D2
D1
D0
W/O
W/O
W/O
W/O
W/O
W/O
W/O
W/O
BIT
7–0
NAME
D[7:0]
RESET
0
FUNCTION
8-bit output data to an I2C device
10.2 Random-Read Operation
A random read requires a dummy byte-write sequence to load in the data word address. Once the device-address
word and the data-word address are clocked out and acknowledged by the device, the MCU starts a current-address
sequence. The following describes the sequence of events to accomplish this transaction.
Device Address + EPROM [High Byte]
• The MCU sets I2CSTA[SRD] = 0. This forces the I2C controller not to generate a stop condition after the
contents of the I2CDAI register are received.
• The MCU sets I2CSTA[SWR] = 0. This forces the I2C controller not to generate a stop condition after the
contents of the I2CDAO register are transmitted.
• The MCU writes the device address (R/W bit = 0) to the I2CADR register (write operation)
• The MCU writes the high byte of the E2PROM address into the I2CDAO register (this starts the transfer on
the SDA line).
• The TXE bit in the I2CSTA register is cleared (indicates busy).
• The content of the I2CADR register is transmitted to E2PROM (preceded by start condition on SDA).
10–2
•
•
•
The contents of the I2CDAO register are transmitted to E2PROM. (EPROM address).
The TXE bit in the I2CSTA register is set and interrupts the MCU, indicating that the I2CDAO register has
been transmitted.
A stop condition is not generated.
EPROM [Low Byte]
• The MCU writes the low byte of the E2PROM address into the I2CDAO register.
• The TXE bit in the I2CSTA register is cleared (indicates busy).
• The contents of the I2CDAO register are transmitted to the device (E2PROM address).
• The TXE bit in the I2CSTA register is set and interrupts the MCU, indicating that the I2CDAO register has
been transmitted.
• This completes the dummy write operation. At this point, the E2ROM address is set and the MCU can do
either a single- or a sequential-read operation.
10.3 Current-Address Read Operation
Once the E2PROM address is set, the MCU can read a single byte by executing the following steps:
• The MCU sets I2CSTA[SRD] = 1. This forces the I2C controller to generate a stop condition after the
I2CDAI-register contents are received.
• The MCU writes the device address (R/W bit = 1) to the I2CADR register (read operation).
• The MCU writes a dummy byte to the I2CDAO register (this starts the transfer on SDA line).
• The RXF bit in the I2CSTA register is cleared.
• The contents of the I2CADR register are transmitted to the device (preceded by start condition on SDA).
• The data from E2PROM are latched into the I2CDAI register (stop condition is transmitted).
• The RXF bit in the I2CSTA register is set and interrupts the MCU, indicating that the data are available.
• The MCU reads the I2CDAI register. This clears the RXF bit (I2CSTA[RXF] = 0).
• End
10.4 Sequential-Read Operation
Once the E2PROM address is set, the MCU can execute a sequential read operation by executing the following (this
example illustrates a 32-byte sequential read):
Device Address
• The MCU sets I2CSTA[SRD] = 0. This forces the I2C controller not to generate a stop condition after the
I2CDAI register contents are received.
• The MCU writes the device address (R/W bit = 1) to the I2CADR register (read operation).
• The MCU writes a dummy byte to the I2CDAO register (this starts the transfer on the SDA line).
• The RXF bit in the I2CSTA register is cleared.
• The contents of the I2CADR register are transmitted to the device (preceded by start condition on SDA).
N-Byte Read (31 Bytes)
• The data from the device are latched into the I2CDAI register (stop condition is not transmitted).
• The RXF bit in the I2CSTA register is set and interrupts the MCU, indicating that data are available.
• The MCU reads the I2CDAI register. This clears the RXF bit (I2CSTA[RXF] = 0).
• This operation repeats 31 times.
Last-Byte Read (Byte 32)
• MCU sets I2CSTA[SRD] = 1. This forces the I2C controller to generate a stop condition after the I2CDAI
register contents are received.
10–3
•
•
•
•
The data from the device is latched into the I2CDAI register (stop condition is transmitted).
The RXF bit in the I2CSTA register is set and interrupts the MCU, indicating that data are available.
The MCU reads the I2CDAI register. This clears the RXF bit (I2CSTA[RXF] = 0)
End
10.5 Byte-Write Operation
The byte-write operation involves three phases: device address + EPROM [high byte] phase, EPROM [low byte]
phase, and EPROM [DATA] phase. The following describes the sequence of events to accomplish the byte-write
transaction.
Device Address + EPROM [High Byte]
• The MCU sets I2CSTA[SWR] = 0. This forces the I2C controller to not generate a stop condition after the
contents of the I2CDAO register are transmitted.
• The MCU writes the device address (R/W bit = 0) to the I2CADR register (write operation).
• The MCU writes the high byte of the E2PROM address into the I2CDAO register (this starts the transfer
on the SDA line).
• The TXE bit in the I2CSTA register is cleared (indicates busy).
• The contents of the I2CADR register are transmitted to the device (preceded by start condition on SDA).
• The contents of the I2CDAO register are transmitted to the device (E2PROM high address).
• The TXE bit in the I2CSTA register is set and interrupts the MCU, indicating that the I2CDAO register
contents have been transmitted.
EPROM [Low Byte]
• The MCU writes the low byte of the E2PROM address into the I2CDAO register.
• The TXE bit in the I2CSTA register is cleared (indicating busy).
• The contents of the I2CDAO register are transmitted to the device (E2PROM address).
• The TXE bit in the I2CSTA register is set and interrupts the MCU, indicating that the I2CDAO register
contents have been transmitted.
EPROM [DATA]
• The MCU sets I2CSTA[SWR] = 1. This forces the I2C controller to generate a stop condition after the
contents of I2CDAO register are transmitted.
• The The data to be written to E2PROM is written by the MCU into the I2CDAO register.
• The TXE bit in the I2CSTA register is cleared (indicates busy).
• The contents of the I2CDAO register are transmitted to the device (E2PROM data).
• The TXE bit in the I2CSTA register is set and interrupts the MCU, indicating that the I2CDAO register
contents have been transmitted.
• The I2C controller generates a stop condition after the contents of the I2CDAO register are transmitted.
• End
10–4
10.6 Page-Write Operation
The page-write operation is initiated in the same way as byte write, with the exception that a stop condition is not
generated after the first EPROM [DATA] is transmitted. The following describes the sequence of writing 32 bytes in
page mode.
Device Address + EPROM [High Byte]
• The MCU sets I2CSTA[SWR] = 0. This forces the I2C controller not to generate a stop condition after the
contents of the I2CDAO register are transmitted.
• The MCU writes the device address (R/W bit = 0) to the I2CADR register (write operation).
• The MCU writes the high byte of the E2PROM address into the I2CDAO register
• The TXE bit in the I2CSTA register is cleared (indicating busy).
• The contents of the I2CADR register are transmitted to the device (preceded by start condition on SDA).
• The contents of the I2CDAO register are transmitted to the device (E2PROM address).
• The TXE bit in the I2CSTA register is set and interrupts the MCU, indicating that the I2CDAO register
contents have been transmitted.
EPROM [Low Byte]
• The MCU writes the low byte of the E2PROM address into the I2CDAO register.
• The TXE bit in the I2CSTA register is cleared (indicates busy).
• The contents of the I2CDAO register are transmitted to the device (E2PROM address).
• The TXE bit in the I2CSTA register is set and interrupts the MCU, indicating that the I2CDAO register
contents have been transmitted.
EPROM [DATA]—31 Bytes
• The data to be written to the E2PROM are written by the MCU into the I2CDAO register.
• The TXE bit in the I2CSTA register is cleared (indicates busy).
• The contents of the I2CDAO register are transmitted to the device (E2PROM data).
• The TXE bit in the I2CSTA register is set and interrupts the MCU, indicating that the I2CDAO register
contents have been transmitted.
• This operation repeats 31 times.
EPROM [DATA]—Last Byte
• The MCU sets I2CSTA[SWR] = 1. This forces the I2C controller to generate a stop condition after the
contents of the I2CDAO register are transmitted.
• The MCU writes the last date byte to be written to the E2PROM, into the I2CDAO register.
• The TXE bit in the I2CSTA register is cleared (indicates busy).
• The contents of the I2CDAO register are transmitted to E2PROM (E2PROM data).
• The TXE bit in the I2CSTA register is set and interrupts the MCU, indicating that the I2CDAO register
contents have been transmitted.
• The I2C controller generates a stop condition after the contents of the I2CDAO register are transmitted.
• End of 32-byte page-write operation.
10–5
10–6
11 TUSB3410 Bootcode Flow
11.1 Introduction
TUSB3410 bootcode is a program embedded within TUSB3410 device. This program is designed to load application
firmware from either external memory device or USB host bootloader device driver. After finished downloading,
bootcode releases its control to the application firmware.
This document describes how the bootcode initializes the TUSB3410 device in detail. In addition, the default USB
descriptor, I2C device header format, USB host driver firmware downloading format, and supported built-in USB
vendor specific requests are listed for reference. Users should carefully follow the appropriate format to interface with
the bootcode. All unsupported formats might cause unexpected results.
The bootcode source code is also provided for programming reference.
11.2 Bootcode Programming Flow
After power-on reset, the bootcode initializes the I2C and USB registers along with internal variables. The bootcode
then checks to see if the I2C device contains a valid signature. If the I2C device has a valid signature, the bootcode
continues searching for descriptor blocks and then processes them if the checksum is correct. If application firmware
was found, the bootcode downloads it and releases the control to the application firmware. Otherwise, the bootcode
connects to the USB and waits for host driver to download application firmware. Once firmware downloading is
finished, the bootcode releases the control to the firmware.
The following is the bootcode step-by-step operation.
•
Check if bootcode is in the application mode. If the bootcode is in the application mode, the bootcode
releases the control to the application firmware. Otherwise, the bootcode continues.
•
Initialize all the default settings.
– Call CopyDefaultSettings() routine.
–
Set I2C to 400-kHz speed.
Call UsbDataInitialization() routine.
Set bFUNADR = 0
Disconnect from USB (bUSBCTL = 0x00)
Bootcode handles USB reset
Copy predefined device, configuration, and string descriptors to RAM
Disable all endpoints and enable USB interrupt(SETUP, RSTR, SUSPR, and RESU)
•
Search for product signature
–
Check if valid signature is in I2C. If not, skip I2C process.
Read 2 bytes from address 0x0000 with type III and device address 0. Stop searching if valid
signature is found.
Read 2 bytes from address 0x0000 with type II and device address 4. Stop searching if valid
signature is found.
•
Load customized device, configuration and string descriptors from I2C EEPROM.
– Process each descriptor block from I2C until end of header is found
If descriptor block is device, configuration or string descriptors, the bootcode overwrites the default
descriptors.
If descriptor block is binary firmware, the bootcode makes a note and loads the firmware later on.
11–1
If descriptor block is auto-execution firmware, the bootcode loads it and releases the control to the
firmware.
If descriptor block is end of header, the bootcode stops searching.
•
Set header pointer to the beginning of the binary firmware in I2C EEPROM.
•
Enable global and USB interrupts and set connection bit to 1.
•
•
•
•
•
–
Set global interrupt bit. EA = 1.
–
Set internal interrupt bit. EX0 = 1.
–
Set connection bit. CONT = 1.
Wait for any interrupt events until Get DEVICE DESCIPTOR setup packet arrives.
–
Suspend interrupt
Set IDLE = 1 to enter suspend mode. USB reset wakes up the microcontroller.
–
Resume interrupt
Bootcode wakes up and waits for new USB requests.
–
Reset interrupt
Call UsbReset() routine.
–
Setup interrupt
Bootcode process the request.
–
Reboot
If Reboot=1, disconnect from USB and restart at address 0x0000.
Download firmware from I2C EEPROM
–
Disable global interrupt. Reset EA = 0.
–
Load firmware to xdata space if available.
Download firmware from USB.
–
If no firmware in I2C EEPROM, host downloads firmware via output endpoint 1.
–
In the first data packet to output endpoint 1, host driver add 3 bytes before the application firmware in
binary format. These three bytes are LSB and MSB of firmware size and then arithmetic checksum of
binary firmware.
Release control to firmware.
–
Update USB configuration and interface number.
–
Release control to application firmware.
Application firmware
–
Either disconnect from bus or continue responding to USB requests.
11.3 Default Bootcode Settings
The bootcode has its own predefined device, configuration, and string descriptors. These default descriptors should
be used in evaluation only. They should not be used in end-user product.
11–2
11.3.1 Device Descriptor
Device descriptor describes the USB version that the device supports, device class, protocol, vendor, product
identifications, strings, and number of configuration. The OS (operation system like Windows, MAC, or Linux) reads
this descriptor to decide which device driver should be used to communicate to this device.
The bootcode uses 0x0451(Texas Instruments) as vendor ID and 0x3410(TUSB3410) as product ID. It also supports
three different strings and one configuration. Table 11–1 lists the device descriptor.
Table 11–1. Device Descriptor
OFFSET
FIELD
SIZE
VALUE
0
bLength
1
0x12
DESCRIPTION
1
bDescriptorType
1
1
2
bcdUSB
2
0x0110
4
bDeviceClass
1
0xFF
5
bDeviceSubClass
1
0
We have no subclasses.
6
bDeviceProtocol
1
0
We use no protocols.
7
bMaxPacketSize0
1
8
Max. packet size for endpoint zero
8
idVendor
2
0x0451
USB–assigned vendor ID = TI
10
idProduct
2
0x3410
TI part number = TUSB3410
12
bcdDevice
2
0x100
Device release number = 1.0
14
iManufacturer
1
1
Index of string descriptor describing manufacturer
15
iProducct
1
2
Index of string descriptor describing product
16
iSerialNumber
1
3
Index of string descriptor describing device’s serial number
17
bNumConfigurations
1
1
Number of possible configurations:
Size of this descriptor in bytes
Device Descriptor type
USB spec 1.1
Device class is vendor–specific
11.3.2 Configuration Descriptor
The configuration descriptor describes the number of interfaces supported by this configuration, power configuration,
and current consumption.
The bootcode declares only one interface running in bus-powered mode. It consumes up to 100 mA at boot time.
Table 11–2 lists the configuration descriptor.
Table 11–2. Configuration Descriptor
OFFSET
FIELD
SIZE
VALUE
0
bLength
1
9
Size of this descriptor in bytes.
DESCRIPTION
1
bDescriptor Type
1
2
Configuration descriptor type
2
wTotalLength
2
25 = 9 + 9 + 7
4
bNumInterfaces
1
1
Number of interfaces supported by this configuration
5
bConfigurationValue
1
1
Value to use as an argument to the SetConfiguration() request to select this
configuration.
6
iConfiguration
1
0
Index of string descriptor describing this configuration.
7
bmAttributes
1
0x80
Configuration characteristics
D7:
Reserved (set to one)
D6:
Self-powered
D5:
Remote wakeup is supported
D4–0:
Reserved (reset to zero)
8
bMaxPower
1
0x32
This device consumes 100 mA.
Total length of data returned for this configuration. Includes the combined length
of all descriptors (configuration, interface, endpoint, and class- or
vendor-specific) returned for this configuration.
11–3
11.3.3 Interface Descriptor
The interface descriptor describes the number of endpoints supported by this interface as well as interface class,
subclass, and protocol.
The bootcode supports only one endpoint and use its own class. Table 11–3 lists the interface descriptor.
Table 11–3. Interface Descriptor
OFFSET
FIELD
SIZE
VALUE
0
bLength
1
9
Size of this descriptor in bytes
DESCRIPTION
1
bDescriptorType
1
4
Interface descriptor type
2
bInterfaceNumber
1
0
Number of interface. Zero-based value identifying the index in the array of concurrent
interfaces supported by this configuration.
3
bAlternateSetting
1
0
Value used to select alternate setting for the interface identified in the prior field
4
bNumEndpoints
1
1
Number of endpoints used by this interface (excluding endpoint zero). If this value is
zero, this interface only uses the default control pipe.
5
bInterfaceClass
1
0xFF
6
bInterfaceSubClass
1
0
7
bInterfaceProtocol
1
0
8
iInterface
1
0
The interface class is vendor specific.
Index of string descriptor describing this interface
11.3.4 Endpoint Descriptor
The endpoint descriptor describes the type and size of communication pipe supported by this endpoint.
The bootcode supports only one output endpoint with the size of 64 bytes in addition to control endpoint 0 (required
by all USB devices). Table 11–4 lists the endpoint descriptor.
Table 11–4. Output Endpoint1 Descriptor
OFFSET
FIELD
SIZE
VALUE
0
bLength
1
7
Size of this descriptor in bytes
1
bDescriptorType
1
5
Endpoint descriptor type
2
bEndpointAddress
1
0x01
3
bmAttributes
1
2
Bit 1…0: Transfer type
10 = Bulk
11 = Interrupt
4
wMaxPacketSize
2
64
Maximum packet size this endpoint is capable of sending or receiving when this
configuration is selected.
6
bInterval
1
0
Interval for polling endpoint for data transfers. Expressed in milliseconds.
11–4
DESCRIPTION
Bit 3…0: The endpoint number
Bit 7:
Direction
0 = OUT endpoint
1 = IN endpoint
11.3.5 String Descriptor
The string descriptor contains string in the unicode format. It is used to show the manufacturers name, product model,
and serial number in human readable format.
The bootcode supports three strings. The first string is the manufacturers name, the second string is the product
name, and the last string is the serial number. Table 11–5 lists the string descriptor.
Table 11–5. String Descriptor
OFFSET
FIELD
SIZE
VALUE
0
bLength
1
4
DESCRIPTION
1
bDescriptorType
1
0x03
2
wLANGID[0]
2
0x0409
4
bLength
1
36
5
bDescriptorType
1
0x03
6
bString
2
‘T’,0x00
Unicode, T is the first byte
8
2
‘e’,0x00
Texas Instruments
10
2
‘x’,0x00
12
2
‘a’,0x00
14
2
‘s’,0x00
16
2
‘ ’,0x00
18
2
‘I’,0x00
20
2
‘n’,0x00
22
2
‘s’,0x00
24
2
‘t’,0x00
26
2
‘r’,0x00
28
2
‘u’,0x00
30
2
‘m’,0x00
32
2
‘e’,0x00
34
2
‘n’,0x00
36
2
‘t’,0x00
38
2
‘s’,0x00
Size of string 0 descriptor in bytes
String descriptor type
English
Size of string 1 descriptor in bytes
String descriptor type
40
bLength
1
42
41
bDescriptorType
1
0x03
Size of string 2 descriptor in bytes
STRING descriptor type
42
bString
2
‘T’,0x00
UNICODE, T is first byte
44
2
‘U’,0x00
TUSB3410 boot device
46
2
‘S’,0x00
48
2
‘B’,0x00
50
2
‘3’,0x00
52
2
‘4’,0x00
54
2
‘1’,0x00
56
2
‘0’,0x00
58
2
‘ ‘,0x00
60
2
‘B‘,0x00
62
2
‘o’,0x00
64
2
‘o’,0x00
66
2
‘t’,0x00
68
2
‘ ’,0x00
70
2
‘D’,0x00
11–5
Table 11–5. String Descriptor (Continued)
OFFSET
SIZE
VALUE
72
FIELD
2
‘e‘,0x00
74
2
‘v’,0x00
76
2
‘I,0x00
78
2
‘c’,0x00
80
2
‘e’,0x00
82
bLength
1
34
84
bDescriptorType
1
0x03
86
bString
DESCRIPTION
Size of string 3 descriptor in bytes
STRING descriptor type
2
r0,0x00
UNICODE
88
2
r1,0x00
R0 to rF are BCD of SERNUM0 to
90
2
r2,0x00
SERNUM7 registers. 16 digit hex
92
2
r3,0x00
16 digit hex numbers are created from
94
2
r4,0x00
SERNUM0 to SERNUM7 registers
96
2
r5,0x00
98
2
r6,0x00
100
2
r7,0x00
102
2
r8,0x00
104
2
r9,0x00
106
2
rA,0x00
108
2
rB,0x00
110
2
rC,0x00
112
2
rD,0x00
114
2
rE,0x00
116
2
rF,0x00
11.4 External Device Header Format
The header can be restored in various storage devices such as ROM, parallel/serial EEPROM, I2C, or flash ROM.
A valid header should contain a product signature and one or more descriptor blocks. The descriptor block contains
the descriptor prefix and content. In the descriptor prefix, the data type, size, and checksum are specified to describe
the content. The descriptor content contains the necessary information for the bootcode to process.
The header processing routine always counts from the first descriptor block until the desired block number is reached.
The header reads in descriptor prefix with the size of 4 bytes. This prefix contains the type of block, size, and
checksum. For example, if the bootcode would like to find the position on third descriptor block, it reads in the first
descriptor prefix, calculates the position on the second descriptor prefix based on the size specified in the prefix.
bootcode, then repeats the same calculation to find out the position of the third descriptor block.
Note that the header-processing routine of the TUSB3410 only supports the I2C device. No other storage device
should be used to store header information.
11.4.1 Product Signature
The product signature should be stored at the first 2 bytes of storage device. These 2 bytes should match the product
number. The order of these 2 bytes should be the LSB first and then the MSB. For example, UMP (TUSB5152) is
0x5152. Therefore, the first byte should be 0x52 and the second byte should be 0x51.
The TUSB3410 bootcode searches the first 2 bytes of the I2C device. If the first 2 bytes are not 0x10 and 0x34, the
bootcode skips the header processing.
11–6
11.4.2 Descriptor Block
Each descriptor block contains prefix and content. The size of the prefix is always 4 bytes. It contains the data type,
size, and checksum for data integrity. The descriptor content contains the corresponding information specified in the
prefix. It could be as small as 1 byte or as large as 65535 bytes. The next descriptor immediately follows the previous
descriptor. If there are no more descriptors, an extra byte with a value of zero should be added to indicate the end
of header.
11.4.2.1 Descriptor Prefix
The first byte of the descriptor prefix is the data type. This tells the bootcode how to process the data in the descriptor
content. The second and third bytes are the size of descriptor content. The second byte is the low byte of the size
and the third byte is the high byte. The last byte is the 8-bit arithmetic checksum of descriptor content.
11.4.2.2 Descriptor Content
Information stored in the descriptor content can be the USB information, firmware, or other type of data. The size of
the content should be from 1 byte to 65535 bytes.
11.5 Checksum in Descriptor Block
Each descriptor prefix contains one checksum of the descriptor content. If the checksum is wrong, the bootcode
simply ignores the descriptor block.
11.6 Header Examples
The header can be specified in different ways. The following descriptors show examples of the header format and
the supported descriptor block.
11.6.1 TUSB3410 Bootcode Supported Descriptor Block
The TUSB3410 bootcode supports the following descriptor blocks.
•
•
•
•
•
USB Device Descriptor
USB Configuration Descriptor
USB String Descriptor
Binary Firmware1
Autoexec Binary Firmware2
1 Binary firmware is loaded when the bootcode receives the first get device descriptor request from host. Downloading the firmware should
either continue that request in the data stage or disconnect from the USB and then reconnect to the USB as a new device.
2 The bootcode loads this autoexec binary firmware before it connects to the USB. The firmware should connect to the USB once it is
loaded.
11–7
11.6.2 USB Descriptor Header
Table 11–6 contains the USB device, configuration, and string descriptors for the bootcode. The last byte is zero to
indicate the end of header.
Table 11–6. USB Descriptors Header
OFFSET
TYPE
SIZE
VALUE
0
Signature0
1
0x10
FUNCTION_PID_L
1
Signature1
1
0x34
FUNCTION_PID_H
2
Data Type
1
0x03
USB device descriptor
3
Data Size (low byte)
1
0x12
The device descriptor is 18 bytes.
4
Data Size (high byte)
1
0x00
5
Check Sum
1
0xCC
Checksum of data below
6
bLength
1
0x12
Size of device descriptor in bytes
7
bDescriptorType
1
0x01
Device descriptor type
8
bcdUSB
2
0x0110
10
bDeviceClass
1
0xFF
Device class is vendor-specific
11
bDeviceSubClass
1
0x00
We have no subclasses.
12
bDeviceProtocol
1
0x00
We use no protocols
13
bMaxPacketSize0
1
0x08
Maximum packet size for endpoint zero
14
idVendor
2
0x0451
USB–assigned vendor ID = TI
16
idProduct
2
0x3410
TI part number = TUSB3410
18
bcdDevice
2
0x0100
Device release number = 1.0
20
iManufacturer
1
0x01
Index of string descriptor describing manufacturer
21
iProducct
1
0x02
Index of string descriptor describing product
22
iSerialNumber
1
0x03
Index of string descriptor describing device’s serial number
23
bNumConfigurations
1
0x01
Number of possible configurations:
24
Data Type
1
0x04
USB configuration descriptor
25
Data Size (low byte)
1
0x19
25 bytes
26
Data Size (high byte)
1
0x00
27
Check Sum
1
0xC6
Checksum of data below
28
bLength
1
0x09
Size of this descriptor in bytes
29
bDescriptorType
1
0x02
CONFIGURATION Descriptor type
30
wTotalLength
2
25(0x19) =
9+9+7
32
bNumInterfaces
1
0x01
Number of interfaces supported by this configuration
33
bConfigurationValue
1
0x01
Value to use as an argument to the SetConfiguration() request to select this
configuration
34
iConfiguration
1
0x00
Index of string descriptor describing this configuration.
35
bmAttributes
1
0xE0
Configuration characteristics
D7:
Reserved (set to one)
D6:
Self–powered
D5:
Remote Wakeup is supported
D4–0:
Reserved (reset to zero)
36
bMaxPower
1
0x64
This device consumes 100 mA.
37
bLength
1
0x09
Size of this descriptor in bytes
38
bDescriptorType
1
0x04
INTERFACE descriptor type
39
bInterfaceNumber
1
0x00
Number of interface. Zero-based value identifying the index in the array of
concurrent interfaces supported by this configuration.
11–8
DESCRIPTION
USB spec 1.1
Total length of data returned for this configuration. Includes the combined length of
all descriptors (configuration, interface, endpoint, and class- or vendor-specific)
returned for this configuration.
Table 11–6. USB Descriptors Header (Continued)
OFFSET
TYPE
SIZE
VALUE
DESCRIPTION
40
bAlternateSetting
1
0x00
Value used to select alternate setting for the interface identified in the prior field
41
bNumEndpoints
1
0x01
Number of endpoints used by this interface (excluding endpoint zero). If this value
is zero, this interface only uses the default control pipe.
42
bInterfaceClass
1
0xFF
The interface class is vendor specific.
43
bInterfaceSubClass
1
0x00
44
bInterfaceProtocol
1
0x00
45
iInterface
1
0x00
Index of string descriptor describing this interface
46
bLength
1
0x07
Size of this descriptor in bytes
47
bDescriptorType
1
0x05
ENDPOINT descriptor type
48
bEndpointAddress
1
0x01
Bit 3…0: The endpoint number
Bit 7:
Direction
0 = OUT endpoint
1 = IN endpoint
49
bmAttributes
1
0x02
Bit 1…0: Transfer Type
10 = Bulk
11 = Interrupt
50
wMaxPacketSize
2
0x0040
52
bInterval
1
0x00
Interval for polling endpoint for data transfers. Expressed in milliseconds.
53
Data Type
1
0x05
USB String descriptor
54
Data Size (low byte)
1
0x1A
26(0x1A) = 4 + 6 + 6 + 10
55
Data Size (high byte)
1
0x00
56
Check Sum
1
0x50
Checksum of data below
57
bLength
1
0x04
Size of string 0 descriptor in bytes
58
bDescriptorType
1
0x03
STRING descriptor type
59
wLANGID[0]
2
0x0409
61
bLength
1
0x06
Size of string 1 descriptor in bytes
62
bDescriptorType
1
0x03
STRING descriptor type
63
bString
2
‘T’,0x00
UNICODE, ‘T’ is the first byte.
2
‘I’,0x00
TI = 0x54, 0x49
0x06
Size of string 2 descriptor in bytes
STRING descriptor type
65
Maximum packet size this endpoint is capable of sending or receiving when this
configuration is selected.
English
67
bLength
1
68
bDescriptorType
1
0x03
69
bString
2
‘u’,0x00
UNICODE, ‘u’ is the first byte.
‘uC’ = 0x75, 0x43
71
2
‘C’,0x00
73
bLength
1
0x0A
Size of string 3 descriptor in bytes
74
bDescriptorType
1
0x03
STRING descriptor type
75
bString
2
‘3’,0x00
UNICODE, ‘T’ is the first byte.
77
2
‘4’,0x00
‘3410’ = 0x33, 0x34, 0x31, 0x30
79
2
‘1’,0x00
81
2
‘0’,0x00
1
0x00
83
Data Type
End of header
11–9
11.6.3 Autoexec Binary Firmware
If the application requires firmware loaded prior to USB connection, the following header can be used. The bootcode
loads the firmware and release the control to the firmware directly without connecting to the USB. However, per the
USB specification requirement, any USB device should connect to the bus and respond to the host within the first
100 ms. Therefore, if downloading time is more than 100 ms, the USB and header speed descriptor blocks should
be added before the autoexec binary firmware. Table 11–7 shows an example of autoexec binary firmware header.
Table 11–7. Autoexec Binary Firmware
OFFSET
TYPE
SIZE
VALUE
0x0000
Signature0
1
0x10
FUNCTION_PID_L
DESCRIPTION
0x0001
Signature1
1
0x34
FUNCTION_PID_H
0x0002
Data Type
1
0x07
Autoexec binary firmware
0x0003
Data Size (low byte)
1
0x67
0x4567 bytes of application code
0x0004
Data Size (high byte)
1
0x45
0x0005
Check Sum
1
0xNN
0x0006
Program
0x4567
0x456d
Data Type
1
Checksum of the following firmware
Binary application code
0x00
End of header
11.7 Host Driver Downloading Header Format
If firmware downloading from the host driver is desired, the host driver should follow the format in Table 11–8. The
Texas Instruments bootloader driver generates the proper format. Therefore, users only need to provide the binary
image of the application firmware for the Bootloader. If the checksum is wrong, the bootcode disconnects from the
USB and waits before it reconnects to the USB.
Table 11–8. Host Driver Downloading Format
11–10
OFFSET
TYPE
SIZE
VALUE
0x0000
Firmware size (low byte)
1
0xXX
0x0001
Firmware size (low byte)
1
0xYY
0x0002
Checksum
1
0xZZ
0x0003
Program
0xYYXX
DESCRIPTION
Application firmware size
Checksum of binary application code
Binary application code
11.8 Built-In Vendor Specific USB Requests
The bootcode supports several vendor specific USB requests. These requests are primarily for internal testing only.
These functions should not be used in normal operation.
11.8.1 Reboot
The reboot command forces the bootcode to reboot. The bootcode starts over.
bmRequestType
USB_REQ_TYPE_DEVICE |
USB_REQ_TYPE_VENDOR |
USB_REQ_TYPE_OUT
01000000b
bRequest
BTC_REBOOT
0x85
wValue
None
0x0000
wIndex
None
0x0000
wLength
None
0x0000
Data
None
11.8.2 Force Execute Firmware
The force execute firmware command requests the bootcode to execute the downloaded firmware unconditionally.
bmRequestType
USB_REQ_TYPE_DEVICE |
USB_REQ_TYPE_VENDOR |
USB_REQ_TYPE_OUT
01000000b
bRequest
BTC_FORCE_EXECUTE_FIRMWARE
0x8F
wValue
None
0x0000
wIndex
None
0x0000
wLength
None
0x0000
Data
None
11.8.3 External Memory Read
The bootcode returns the content of the specified address.
bmRequestType
USB_REQ_TYPE_DEVICE |
USB_REQ_TYPE_VENDOR |
USB_REQ_TYPE_IN
11000000b
bRequest
BTC_EXETERNAL_MEMORY_READ
0x90
wValue
None
0x0000
wIndex
Data address
0xNNNN (From 0x0000 to 0xFFFF)
wLength
1 byte
0x0001
Data
Byte in the specified address
0xNN
11.8.4 External Memory Write
The external memory write command tells the bootcode to write data to the specified address.
bmRequestType
USB_REQ_TYPE_DEVICE |
USB_REQ_TYPE_VENDOR |
USB_REQ_TYPE_OUT
01000000b
bRequest
BTC_EXETERNAL_MEMORY_WRITE
0x91
wValue
HI: 0x00
LO: Data
0x00NN
wIndex
Data address
0xNNNN (From 0x0000 to 0xFFFF)
wLength
None
0x0000
Data
None
11–11
11.8.5 I2C Memory Read
The bootcode returns the content of the specified address in I2C EEPROM.
In the wValue field, the I2C device number is from 0x00 to 0x07 in high filed. The memory type is from 0x01 to 0x03
for CAT I to CAT III devices. If bit 7 of bValueL is set, then 400 kHz is used. Otherwise, 100 kHz is used. This request
is also used to set the device number and speed before the I2C write request.
bmRequestType
USB_REQ_TYPE_DEVICE |
USB_REQ_TYPE_VENDOR |
USB_REQ_TYPE_IN
11000000b
bRequest
BTC_I2C_MEMORY_READ
HI:
I2C device number
LO:
Memory type bit[1:0]
Speed bit[7]
0x92
wValue
wIndex
Data address
0xNNNN (From 0x0000 to 0xFFFF)
wLength
1 byte
0x0001
Data
Byte in the specified address
0xNN
0xXXYY
11.8.6 I2C Memory Write
The I2C memory write command tells the bootcode to write data to the specified address. The SPI mode setting is
done in the SPI read command.
bmRequestType
USB_REQ_TYPE_DEVICE |
USB_REQ_TYPE_VENDOR |
USB_REQ_TYPE_OUT
01000000b
bRequest
BTC_I2C_MEMORY_WRITE
0x93
wValue
HI: should be zero
LO: Data
0x00NN
wIndex
Data address
0xNNNN (From 0x0000 to 0xFFFF)
wLength
None
0x0000
Data
None
11.8.7 Internal ROM Memory Read
The bootcode returns the byte of the specified address in ROM. That is, the binary code of the bootcode.
bmRequestType
USB_REQ_TYPE_DEVICE |
USB_REQ_TYPE_VENDOR |
USB_REQ_TYPE_OUT
01000000b
bRequest
BTC_INTERNAL_ROM_MEMORY_READ
0x94
wValue
None
0x0000
wIndex
Data address
0xNNNN (From 0x0000 to 0xFFFF)
wLength
1 byte
0x0001
Data
Byte in the specified address
0xNN
11–12
11.9 Bootcode Programming Consideration
11.9.1 USB Requests
For each USB request, the bootcode follows the steps below to ensure proper operation of the hardware.
1. Determine the direction of the request by checking the MSB of the bmRequestType field and set the
USBCTL_DIR bit accordingly.
2. Decode the command
3. If another setup is pending, then return. Otherwise, serve the request.
4. Check again, if another setup is pending then go to step 2.
5. Clear the interrupt source and then the VECINT register.
6. Exit the interrupt routine.
11.9.1.1 USB Requests
The USB request consist of three types of transfers. They are control-read-with-data-stage, control-writewithout-data-stage, and control-write-with-data-stage transfer. In each transfer, arrows indicate interrupts generated
after receiving the setup packet, in or out token.
Figure 11–1 and Figure 11–2 show the USB data flow and how the hardware and firmware respond to the USB
requests. Table 11–9 and Table 11–10 lists the bootcode reposes to the standard USB requests.
Setup Stage
Data Stage
Setup (0)
IN(1)
INT
1.Hardware generates interrupt
to MCU.
2.Hardware sets NAK on both
endpoints.
3.Set DIR bit in USBCTL to
indicate the data directory.
3.Decode the setup packet
4.If another setup packet
arrives, abandon this one.
5.Executes appropriate routines.
a) Clear NAK bit in OUT
endpoint.
b) Copy data to IN endpoint
buffer and set byte count.
More
Packets
IN(0)
INT
INT
1.Hardware generates interrupt to
MCU.
2.Copy data to IN buffer.
3.Clear the NAK bit.
4.If all data has been sent out,
stall input endpoint.
StatusStage
IN(0/1)
OUT(1)
INT
1.Hardware does NOT generate
interrupt to MCU.
Figure 11–1. Control Read Transfer
11–13
Table 11–9. Bootcode Response to Control Read Transfer
CONTROL READ
ACTION IN BOOTCODE
Get status of device
Return power and remote wakeup settings
Get status of interface
Return 2 bytes of zeros
Get status of endpoint
Return endpoint status
Get descriptor of device
Return device descriptor
Get descriptor of configuration
Return configuration descriptor
Get descriptor of string
Return string descriptor
Get descriptor of interface
Stall
Get descriptor of endpoint
Stall
Get configuration
Return bConfiguredNumber value
Get interface
Return bInterfaceNumber value
Setup Stage
Status Stage
Setup (0)
IN(1)
INT
1.Hardware generates interrupt
to MCU.
2.Hardware sets NAK on both
endpoints.
3.Set DIR bit in USBCTL to
indicate the data directory.
3.Decode the setup packet
4.If another setup packet
arrives, abandon this one.
5.Executes appropriate routines.
a) Clear NAK bit in IN
endpoint.
b) Keep a note so IN interrupt
routine can take proper
action to the request.
1.Hardware does NOT generates
interrupt to MCU.
Figure 11–2. Control Write Transfer Without Data Stage
Table 11–10. Bootcode Response to Control Write Without Data Stage
11–14
CONTROL WRITE WITHOUT DATA STAGE
ACTION IN BOOTCODE
Clear feature of device
Stall
Clear feature of interface
Stall
Clear feature of endpoint
Clear endpoint stall
Set feature of device
Stall
Set feature of interface
Stall
Set feature of endpoint
Stall endpoint
Set address
Set device address
Set descriptor
Stall
Set configuration
Set bConfiguredNumber
Set interface
SetbInterfaceNumber
Sync. frame
Stall
11.9.1.2 Interrupt Handling Routine
The higher-vector number has a higher priority than the lower-vector number. Table 11–11 lists all the interrupts and
source of interrupts.
Table 11–11. Vector Interrupt Values and Sources
G[3:0]
(Hex)
I[2:0]
(Hex)
VECTOR
(Hex)
0
0
00
No Interrupt
No Source
1
1
10
Output–endpoint–1
VECINT register
1
2
12
Output–endpoint–2
VECINT register
1
3
14
Output–endpoint–3
VECINT register
1
4
16
Output–endpoint–4
VECINT register
2
4–7
18→1E
2
1
20
Input–endpoint–1
VECINT register
2
2
22
Input–endpoint–2
VECINT register
2
3
24
Input–endpoint–3
VECINT register
2
4
26
Input–endpoint–4
VECINT register
2
4–7
28→2E
3
0
30
STPOW packet received
USBSTA/ VECINT registers
3
1
32
SETUP packet received
USBSTA/ VECINT registers
3
2
34
PSOF interrupt
USBSTA/ VECINT registers
3
3
36
RESR interrupt
USBSTA/ VECINT registers
3
4
38
FSPR interrupt
USBSTA/ VECINT registers
3
5
3A
RTSR interrupt
USBSTA/ VECINT registers
3
6
3C
HSTL interrupt
USBSTA/ VECINT registers
3
7
3E
NOT USED
4
0
40
I2C TXE interrupt
VECINT register
4
1
42
I2C TXE interrupt
VECINT register
4
2
44
Input–endpoint–0
VECINT register
4
3
46
Output–endpoint–0
VECINT register
4
4–7
48→4E
5
0
50
UART1 status interrupt
LSR/VECNT register
5
1
52
UART1 modern interrupt
LSR/VECINT register
5
3–7
54→5E
6
0
60
UART1 RXF interrupt
LSR/VECNT register
6
1
62
UART1 TXE interrupt
LSR/VECINT register
6
2–7
64→6E
NOT USED
7
0–7
70→7E
NOT USED
8
0
80
DMA1 interrupt
8
1
82
NOT USED
8
2
84
DMA3 interrupt
8
3–7
86→7E
NOT USED
9–15
0–7
90→FE
NOT USED
INTERRUPT SOURCE
INTERRUPT SOURCE SHOULD BE
CLEARED
NOT USED
NOT USED
NOT USED
NOT USED
DMACSR/VECNT register
DMACSR/VECNT register
11–15
11.9.2 Hardware Reset Introduced by the Firmware
This feature can be used in firmware upgrade. Once the upgrade is done, the application firmware disconnects from
the USB for at least 200 ms to ensure OS has unloaded the device driver. The firmware then enables the watchdog
timer (enabled by default after power-on reset) and enters an endless loop without resetting the watchdog timer. Once
the watchdog timer times out, it resets the chip as if the chip gets the power-on reset. The bootcode takes over control
and starts the power-on sequence again.
11.10 File Listings
The bootload code can be obtained from the TI website under SLLS519.code.zip. The list shown below are the names
of the files that can be downloaded.
11–16
•
Types.h
•
USB.h
•
TUSB3410.h
•
Bootcode.h
•
Watchdog.h
•
Bootcode.c
•
Bootlsr.c
•
BootUSB.c
•
Header.h
•
Header.c
•
I2c.h
•
I2c.c
12 Electrical Specifications
12.1 Absolute Maximum Ratings†
Supply voltage, VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to 3.6 V
Input voltage, VI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to VCC + 0.5 V
Output voltage, VO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to VCC + 0.5 V
Input clamp current, IIK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±20 mA
Output clamp current, IOK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±20 mA
† Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
12.2 Commercial Operating Condition (3.3 V)
MIN
TYP
MAX
UNIT
VCC
VI
Supply voltage
PARAMETER
3
3.3
3.6
V
Input voltage
0
V
VIH
High level input voltage
High-level
VCC
VCC
VIL
Low level input voltage
Low-level
TA
Operating temperature
TTL
2
0.7 × VCC
CMOS
V
TTL
0
VCC
0.8
CMOS
0
0.2 × VCC
V
0
70
°C
12.3 Electrical Characteristics TA = 25°C, VCC = 3.3 V ±5%, VSS = 0 V
PARAMETER
TEST CONDITIONS
TTL
4 mA
IOH = –4
MIN
TYP
MAX
VCC – 0.5
VCC – 0.5
UNIT
VOH
High level output voltage
High-level
VOL
Low level output voltage
Low-level
VIT+
Positive threshold voltage
VIT–
Negative threshold voltage
Vhys
Hysteresis (VIT+ – VIT–)
IIH
High level input current
High-level
IIL
Low level input current
Low-level
IOZ
IOL
Output leakage current (Hi-Z)
Output low drive current
0.1
mA
IOH
Output high drive current
Clock duty cycle‡
0.1
mA
CMOS
TTL
CMOS
V
0.5
IOL = 4 mA
0.5
TTL
CMOS
1.8
VI = VIH
TTL
CMOS
0.7 × VCC
0.8
VI = VIH
TTL
CMOS
VI = VIH
V
0.3
0.7
0.17 × VCC
0.3 × VCC
±20
VI = VIH
±1
±20
TTL
Jitter specification‡
CI
Input capacitance
CO
Output capacitance
‡ Applies to all clock outputs
CMOS
V
1.8
0.2 × VCC
TTL
CMOS
V
VI = VIL
±1
±20
VI = VCC or VSS
V
A
µA
µA
A
µA
50%
±100
ppm
18
pF
10
pF
12–1
12–2
13 Application Notes
13.1 Crystal Selection
The TUSB3410 requires a 12-MHz clock source to work properly. This clock source can be a crystal placed across
the X1 and X2 terminals. A parallel resonant crystal is recommended. Most parallel resonant crystals are specified
at a frequency with a load capacitance of 18 pF. This load can be realized by placing 33-pF capacitors from each end
of the crystal to ground. Together with the input capacitance of the TUSB3410 and stray board capacitance, this
provides close to two 36-pF capacitors in series to emulate the 18-pF load requirement. Note, that when using a
crystal, it takes about 2 ms after power up for a stable clock to be produced.
TUSB3410
33 pF
X2
33 pF
12 MHz
X1
Figure 13–1. Crystal Selection
13.2 External Circuit Required for Reliable Bus Powered Suspend Operation
TI has found a potential problem with the action of the SUSPEND output pin immediately after power on. In some
cases the SUSPEND pin can power up asserted high. When used in a bus powered application this can cause a
problem because the VREGEN# input is usually connected to the SUSPEND output. This in turn causes the internal
1.8-V voltage regulator to shut down, which means an external crystal may not have time to begin oscillating, thus
the device will not initialize itself correctly.
TI has determined an on-chip fix for this problem, but has not determined a schedule on when the fix will be
implemented. In the meantime, the components R2 and D1 (rated to 25 mA) in the circuit shown below can be used
as a workaround. Note that R1 and C1 are required components for proper reset operation, unless the reset signal
is provided by another means. R2 and D1 can be left in place or removed once the silicon is modified.
Note that use of an external oscillator (1.8-V output) versus a crystal would avoid this situation, but it is not expected
that many applications would use an oscillator. Also note that self-powered applications would probably not see this
problem because the VREGEN# input would likely be tied low, enabling the internal 1.8-V regulator at all times.
13–1
3.3 V
TUSB3410
R1
15 kΩ
RESET
R2
32 kΩ
VREGEN
C1
1 µF
D1
SUSPEND
Figure 13–2. External Circuit
13.3 Wakeup Timing From WAKEUP or RI Pin
The TUSB3410 can be brought out of the suspended state, or woken up, by a command from the host. The TUSB3410
also supports remote wakeup and can be awakened by either of two input signals. A low pulse on the WAKEUP pin
or a low-to-high transition on the RI pin wakes the device up. Note that for reliable operation, either condition must
persist for approximately 3 ms minimum. This allows time for the crystal to power up since in the suspend mode the
crystal interface is powered down. The state of the WAKEUP or RI pin is then sampled by the clock to verify there
was a valid wakeup event.
13–2
14 Mechanical
VF (S-PQFP-G32)
PLASTIC QUAD FLATPACK
0,45
0,30
0,80
24
0,22 M
17
25
16
32
9
0,13 NOM
1
8
5,60 TYP
7,20
SQ
6,80
9,20
SQ
8,80
Gage Plane
0,25
1,45
1,35
0,05 MIN
Seating Plane
1,60 MAX
0°–ā7°
0,75
0,45
0,10
4040172 / C 10/96
NOTES: A. All linear dimensions are in millimeters.
B. This drawing is subject to change without notice.
C. Falls within JEDEC MS-026
14–1
14–2