AMD Geode SC1201 - Manual (Page 421)

AMD Geode™ SC1200/SC1201 Processor Data Book 421
Electrical Specifications 32579B
9.3.11 Serial Port (UART)
Figure 9-42. UART, Sharp-IR, SIR, and Consumer Remote Control Timing Diagram
Table 9-32. UART, Sharp-IR, SIR, and Consumer Remote Control Timing Parameters
Symbol Parameter Min Max Unit Comments
t
BT
Single bit time in UART and
Sharp-IR t
BTN
- 25
(Note 1)
t
BTN
+ 25 ns Transmitter
t
BTN
- 2% t
BTN
+ 2% ns Receiver
t
CMW
Modulation signal pulse width in
Sharp-IR and Consumer
Remote Control t
CWN
- 25
(Note 2)
t
CWN
+ 25 ns Transmitter
500 ns Receiver
t
CMP
Modulation signal period in
Sharp-IR and Consumer
Remote Control t
CPN
- 25
(Note 3)
t
CPN
+ 25 ns Transmitter
t
MMIN
(Note 4)
t
MMAX
(Note 4)
ns Receiver
t
SPW
SIR signal pulse width
(
3
/
16
) x t
BTN
- 15
(Note 1)
(
3
/
16
) x t
BTN
+ 15
(Note 1)
ns Transmitter, Variable
1.48 1.78 µs Transmitter, Fixed
1 µs Receiver
S
DRT
SIR data rate tolerance % of
nominal data rate
± 0.87%
Transmitter
± 2.0%
Receiver
t
SJT
SIR leading edge jitter % of
nominal bit duration
± 2.5%
Transmitter
± 6.5%
Receiver
Note 1. t
BTN
is the nominal bit time in UART, Sharp-IR, SIR and Consumer Remote Control modes. It is determined by the
setting of the Baud Generator Divisor registers.
Note 2. t
CWN
is the nominal pulse width of the modulation signal for Sharp-IR and Consumer Remote Control modes. It is
determined by the MCPW field (bits [7:5]) of the IRTXMC register and the TXHSC bit (bit 2) of the RCCFG register.
Note 3. t
CPN
is the nominal period of the modulation signal for Sharp-IR and Consumer Remote Control modes. It is deter-
mined by the MCFR field (bits [4:0]) of the IRTXMC registerand the TXHSC bit (bit 2) of the RCCFG register.
Note 4. t
MMIN
and t
MMAX
define the time range within which the period of the incoming subcarrier signal has to fall in order
for the signal to be accepted by the receiver. These time values are determined by the contents of register IRRXDC
and the setting of the RXHSC bit (bit 5) of the RCCFG register.
t
BT
t
SPW
t
CMP
UART
Sharp IR
Consumer
Remote
SIR
t
CMW
Control