Datasheet
SBAS323G − JUNE 2004 − REVISED OCTOBER 2007
www.ti.com
38
Flash Programming Mode
There are two programming modes: parallel and serial.
The programming mode is selected by the state of the ALE
and PSEN signals during reset (BOR, WDT, software, or
POR). Serial programming mode is selected with PSEN
=
0 and ALE = 1. Parallel programming mode is selected
with PSEN
= 1 and ALE = 0, as shown in Figure 24. If they
are both high, the MSC1211/12/13/14 will operate in User
Application mode. For both signals, low is a reserved
mode and is not defined. Programming mode is exited with
a reset and the normal mode selected.
Figure 25 shows the serial programming conection.
Serial programming mode works through USART0, and
has special protocols. Table 7 describes these protocols,
which are discussed at length in Application Note
SBAA076 (available for download at www.ti.com). The
serial programming mode works at a maximum baud rate
determined by f
OSC
.
PSEN
ALE
MSC1211/12/13/14
HOST
Flash
Programmer
P2[7]
P2[6:0]
P1[7:0]
P0[7:0]
P3[7:5]
P3[4]
P3[3]
P3[2]
RST
XIN
PSEL
AddrHi[6:0]
AddrLo[7:0]
Data[7:0]
Cmd[2:0]
Req
Ack
Pass
RST
CLK
NC
Figure 24. Parallel Programming Configuration
MSC121x
PSEN
P3.0 RXD
P3.1 TXD
Serial
Port 0
ALE
RST DV
DD
X
IN
Reset Circuit (or V
DD
)
Clock Source
Not Connected
RS232
Transceiver
Host PC
or
Serial Terminal
NOTE: Serial programming is selected with PSEN = 0 and ALE = 1 or open.
Figure 25. Serial Programming Connection