6-32
MSM66591/ML66592 User's Manual
Chapter 6 Port Functions
6.15 Port 12 (P12)
Port 12 (P12_0, P12_1) is a 2-bit I/O port. Input or output can be specified for each bit
by the Port 12 mode register (P12IO).
In addition to the port function, a secondary function (for MSM66591, address 16 output
of external program memory; for ML66592, address 16 and 17 output of external
program memory) is assigned to Port 12. If the
EA
pin is set to "L" level, in MSM66591
P12_0 operates as an address bus (address 16 output pin) of the external program
memory, and in ML66592 P12_0 and P12_1 operate as address buses (address 16
and 17 output pins) of the external program memory.
If the
OE
pin (pin 71) is in "L" level when Port 12 is in output status, Port 12 outputs "H"
or "L" level, but if the
OE
pin is in "H" level, Port 12 goes into high impedance status.
Figure 6-18 shows the configuration of the Port 12 data register (P12) and the Port 12
mode register (P12IO).
Figure 6-18 Configuration of P12 and P12IO
If a read instruction is executed to P12 in which input is specified (P12IOn = "0") by
P12IO, the content of the pin is read. If a read instruction is executed to P12 in which
output is specified (P12IOn = "0"), the content of the port data register is read. If an
arithmetic instruction, increment instruction, or instruction of that type (read-modify-
write instruction) is executed to P12, the content of the pin or port data register is read
according to specification by P12IO (in the case of reading), and data is written to the
port data register (in the case of writing).
At reset (when the
RES
signal is input, the BRK instruction is executed, the watchdog
timer is overflown, or an operation code trap is generated), Port 12 becomes a high
impedance input port (P12IO = 00H). The content of P12 becomes 00H.
"0"
"0"
"0"
"0"
"0"
"0"
P12_1
P12_0
7
6
5
4
3
2
1
0
P12
"0"
"0"
"0"
"0"
"0"
"0"
P12IO1 P12IO0
7
6
5
4
3
2
1
0
P12IO
P12_n = input
0
P12_n = output
1
n = 0, 1
"0" indicates a bit that is not provided.
"0" is read if a read instruction
is executed.
When writing to these bits,
always write "0".
Содержание MSM66591
Страница 1: ...MSM66591 ML66592 User s Manual CMOS 16 bit microcontroller FEUL66591 66592 01 Issue Date Mar 4 2002...
Страница 15: ...Contents 12...
Страница 17: ......
Страница 18: ...Overview Chapter 1 1...
Страница 19: ......
Страница 30: ...Description of Pins Chapter 2 2...
Страница 31: ......
Страница 44: ...CPU Architecture Chapter 3 3...
Страница 45: ......
Страница 101: ...3 56 MSM66591 ML66592User sManual Chapter 3 CPU Architecture...
Страница 102: ...CPU Control Functions Chapter 4 4...
Страница 103: ......
Страница 111: ...4 8 MSM66591 ML66592User sManual Chapter 4 CPU Control Functions...
Страница 112: ...Memory Control Functions Chapter 5 5...
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Страница 117: ...5 4 MSM66591 ML66592User sManual Chapter 5 Memory Control Functions...
Страница 118: ...Port Functions Chapter 6 6...
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Страница 152: ...Output Pin Control Pin OE Chapter 7 7...
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Страница 155: ...7 2 MSM66591 ML66592User sManual Chapter 7 Output Pin Control Pin OE...
Страница 156: ...Clock Generation Circuit Chapter 8 8...
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Страница 160: ...Time Base Counter TBC Chapter 9 9...
Страница 161: ......
Страница 164: ...Watchdog Timer WDT Chapter 10 10...
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Страница 170: ...Flexible Timer FTM Chapter 11 11 11...
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Страница 213: ...11 42 MSM66591 ML66592User sManual Chapter 11 Flexible Timer FTM...
Страница 214: ...General Purpose 8 Bit Timer Function Chapter 12 12...
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Страница 223: ...12 8 MSM66591 ML66592User sManual Chapter 12 General Purpose 8 Bit Timer Function...
Страница 224: ...PWM Functions Chapter 13 13...
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Страница 244: ...Baud Rate Generator Functions Chapter 14 14...
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Страница 263: ...14 18 MSM66591 ML66592User sManual Chapter 14 Baud Rate Generator Functions...
Страница 264: ...Serial Port Functions Chapter 15 15...
Страница 265: ......
Страница 348: ...A D Converter Functions Chapter 16 16...
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Страница 381: ...16 32 MSM66591 ML66592User sManual Chapter 16 A D Converter Functions...
Страница 382: ...Transition Detector Functions Chapter 17 17...
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Страница 387: ...17 4 MSM66591 ML66592User sManual Chapter 17 Transition Detector Functions...
Страница 388: ...Peripheral Functions Chapter 18 18...
Страница 389: ......
Страница 392: ...External Interrupt Request Function Chapter 19 19...
Страница 393: ......
Страница 396: ...Interrupt Request Processing Function Chapter 20 20...
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Страница 407: ...20 10 MSM66591 ML66592User sManual Chapter 20 Interrupt Request Processing Function...
Страница 408: ...Bus Port Functions Chapter 21 21...
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Страница 413: ...21 4 MSM66591 ML66592User sManual Chapter 21 Bus Port Functions...
Страница 414: ...Expansion Port Chapter 22 22...
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Страница 420: ...Serial Port with FIFO SCI5 Chapter 23 23...
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Страница 431: ...23 10 MSM66591 ML66592User sManual Chapter 23 Serial Port with FIFO SCI5...
Страница 432: ...RAM Monitor Function Chapter 24 24...
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Страница 441: ...24 8 MSM66591 ML66592User sManual Chapter 24 RAM Monitor Function...
Страница 442: ...25 Electrical Characteristics Chapter 25...
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Страница 458: ...Package Dimensions Chapter 26 26...
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Страница 461: ...26 2 MSM66591 ML66592User sManual Chapter 26 Package Dimensions...
Страница 462: ...Revision History Chapter 27 27...
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Страница 465: ...27 2 MSM66591 ML66592User sManual Chapter 27 Revision History...