W83977F Datasheet, PDF (78/181 Pages) Winbond – PLUG & PLAY 1.0A COMPLIANT

Bit 1:
Bit 0:
W83977F/ W83977AF
PRELIMINARY
TMR_TST - Timer Test
When set to 1, reading the TMRL/TMRH returns the programmed values of TMRL/TMRH
instead of the value of down counter. This bit is for testing timer register.
EN_TMR - Enable Timer
A write to 1 will enable the timer.
4.6.3 Set4.Reg3 - Set Select Register (SSR)
Reading this register returns E8H. Writing this register selects Register Set.
Reg.
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
SSR
Default Value
SSR7
1
SSR6
1
SSR5
1
SSR4
1
SSR3
1
SSR2
0
Bit 1
SRR1
0
Bit 0
SRR0
0
4.6.4 Set4.Reg4, 5 - Transmitter Frame Length (TFRLL/TFRLH)
Reg.
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
TFRLL
Reset Value
TFRLH
Reset Value
bit 7
0
-
-
bit 6
0
-
-
bit 5
bit 4
bit3
0
0
0
-
bit 12 bit 11
-
0
0
Bit 2
bit 2
0
bit 10
0
Bit 1
bit 1
0
bit 9
0
Bit 0
bit 0
0
bit 8
0
These are combined to be a 13-bit register. Writing these registers programs the transmitter frame
length of a package. These registers are only valid when APM=1 (automatic package mode,
Set5.Reg4.bit5). When APM=1, the physical layer will split data stream to a programmed frame
length if the transmitted data is larger than the programmed frame length. When these registers are
read, they will return the number of bytes which is not transmitted from a frame length programmed.
4.6.5 Set4.Reg6, 7 - Receiver Frame Length (RFRLL/RFRLH)
Reg.
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
RFRLL
Reset Value
RFRLH
Reset Value
bit 7
0
-
-
bit 6
0
-
-
bit 5
bit 4
bit 3
0
0
0
-
bit 12 bit 11
-
0
0
Bit 2
bit 2
0
bit 10
0
Bit 1
bit 1
0
bit 9
0
Bit 0
bit 0
0
bit 8
0
These are combined to be a 13-bit registers and up counter. The length of receiver frame will be
limited to the programmed frame length. If the received frame length is larger than the programmed
receiver frame length, the bit of MX_LEX (Maximum Length Exceed) will be set to 1. Simultaneously,
the receiver will not receive any more data to RX FIFO until the next start flag of the next frame,
which is defined in the physical layer IrDA 1.1. Reading these registers returns the number of
received data bytes of a frame from the receiver.
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Publication Release Date: March 1998
Revision 0.58