DAN-133 Datasheet, PDF (6/8 Pages) Exar Corporation – EXAR’S QUARTS COMPARED

DATA COMMUNICATIONS APPLICATION NOTE
DAN133
1.4.4 Firmware Differences Between the TL16C554A and XR16C854
The internal registers in the XR16C854 offers more features than the TL16C554A with these differences:
TABLE 5: XR16C854 AND TL16C554A REGISTER SET DIFFERENCES
A2:A0 R/W
XR16C854
TL16C554A
LCR Bit-7 = 0
001 R/W Interrupt Enable Register (IER)
• Bit-7 = Auto CTS# Interrupt Enable
• Bit-6 = Auto RTS# Interrupt Enable
• Bit-5 = Xoff Interrupt Enable
Interrupt Enable Register (IER)
• Bit-7 = Not Used
• Bit-6 = Not Used
• Bit-5 = Not Used
010
W FIFO Control Register (FCR)
• Bit-5 = TX FIFO Trigger Level Select Bit-1
• Bit-4 = TX FIFO Trigger Level Select Bit-0
FIFO Control Register (FCR)
• Bit-5 = Not Used
• Bit-4 = Not Used
010
R Interrupt Status Register (ISR)
• Bit-5 = Auto RTS/CTS Interrupt
• Bit-4 = Xoff or Special Character Interrupt
Interrupt Status Register (ISR)
• Bit-5 = Not Used
• Bit-4 = Not Used
100 R/W Modem Control Register (MCR)
• Bit-7 = BRG Prescaler
• Bit-6 = IR Mode Enable
• Bit-5 = XonAny
• Bit-2 = OP1 Control/Auto RS485 Enable
Modem Control Register (MCR)
• Bit-7 = Not Used
• Bit-6 = Not Used
• Bit-5 = Auto RTS/CTS Flow Control Enable
• Bit-2 = OP1 Control
LCR Bit-7 = 0, FCTR Bit-6 = 1
111
W Enhanced Mode Select Register (EMSR)
N/A
• RX/TX DMA Select, FLVL select - TX or RX FIFO
111
R FIFO Level Register (FLVL)
N/A
• Current Level of the TX or RX FIFO
LCR Bit-7 = 0, DLL = 0x00, DLM = 0x00
000
R Device Revision (DREV)
N/A
001
R Device ID (DVID)
N/A
LCR = 0xBF
000
R FIFO Data Count Register (FC)
N/A
000
W Trigger Level Register (TRG)
N/A
• Programmable Trigger Levels 1-64 for TX and RX
FIFO
001 R/W Feature Control Register (FCTR)
N/A
• RX/TX Programmable Trigger Level Select,
Scratchpad Swap, Trigger Table Select, Auto
RS485 Enable, RX IR Input Inversion, Auto RTS
Hysteresis Select (LSB)
010 R/W Enhanced Feature Register (EFR)
N/A
• Auto RTS/CTS Enable, Enhanced Functions
Enable, Software Flow Control Select
100 R/W XON1
N/A
101 R/W XON2
N/A
110 R/W XOFF1
N/A
111 R/W XOFF2
N/A
R = Read-Only, W = Write-Only, R/W = Read/Write
6