PIC RS232 - Revision history

Lynch: /* FTDIChip TTL-232R USB to RS232 Cable */

2010-04-10T12:09:31Z

FTDIChip TTL-232R USB to RS232 Cable

Lynch: /* FTDIChip TTL-232R USB to RS232 Cable */

2010-04-10T12:07:15Z

FTDIChip TTL-232R USB to RS232 Cable

Lynch: /* FTDIChip TTL-232R USB to RS232 Cable */

2008-02-22T00:01:02Z

FTDIChip TTL-232R USB to RS232 Cable

Lynch: /* Alternate USB to RS232 Cable */

2008-02-21T23:57:27Z

Alternate USB to RS232 Cable

Lynch: /* Alternate USB to RS232 Cable */

2008-02-21T04:32:08Z

Alternate USB to RS232 Cable

LIMS: /* FTDIChip TTL-232R USB to RS232 Cable */

2008-02-21T02:55:59Z

FTDIChip TTL-232R USB to RS232 Cable

LIMS: /* FTDIChip TTL-232R USB to RS232 Cable */

2008-02-21T02:54:49Z

FTDIChip TTL-232R USB to RS232 Cable

LIMS: /* FTDIChip TTL-232R USB to RS232 Cable */

2008-02-21T02:53:32Z

FTDIChip TTL-232R USB to RS232 Cable

LIMS: /* FTDIChip TTL-232R USB to RS232 Cable */

2008-02-21T02:52:01Z

FTDIChip TTL-232R USB to RS232 Cable

LIMS: /* FTDIChip TTL-232R USB to RS232 Cable */

2008-02-21T02:50:26Z

FTDIChip TTL-232R USB to RS232 Cable

@@ Line 19: / Line 19: @@
 The FTDIChip TTL-232R USB to RS232 cable (pictured at right), when used with the
-<!-- [http://www.ftdichip.com/Drivers/CDM/CDM%202.02.04.exe driver software], (updated below -->
+[http://www.ftdichip.com/Drivers/CDM/CDM%202.02.04.exe driver software],
-[http://www.ftdichip.com/Drivers/VCP.htm driver software],
+<!-- check here:  [http://www.ftdichip.com/Drivers/VCP.htm driver software],-->
 allows you to use your USB port as an RS232 port.  You can find a manual for the cable [[Media:usb-rs232-ftdichip.pdf|here]].  You connect the cable's Tx (transmit data) pin with your PIC's Rx (receive data, pin 26), the cable's Rx pin with your PIC's Tx (pin 25), and the cable's ground with the PIC's ground, and you're all set.  The circuitry inside the cable takes care of the USB to RS232 as well as voltage-level shifting.  This cable also provides a 5V output which you can use to power an xbee wireless modem, for example (the xbee needs a 3.3V regulator).

@@ Line 19: / Line 19: @@
 The FTDIChip TTL-232R USB to RS232 cable (pictured at right), when used with the
+<!-- [http://www.ftdichip.com/Drivers/CDM/CDM%202.02.04.exe driver software], (updated below -->
-[http://www.ftdichip.com/Drivers/CDM/CDM%202.02.04.exe driver software], allows you to use your USB port as an RS232 port.  You can find a manual for the cable [[Media:usb-rs232-ftdichip.pdf|here]].  You connect the cable's Tx (transmit data) pin with your PIC's Rx (receive data, pin 26), the cable's Rx pin with your PIC's Tx (pin 25), and the cable's ground with the PIC's ground, and you're all set.  The circuitry inside the cable takes care of the USB to RS232 as well as voltage-level shifting.  This cable also provides a 5V output which you can use to power an xbee wireless modem, for example (the xbee needs a 3.3V regulator).
+[http://www.ftdichip.com/Drivers/VCP.htm driver software],
+allows you to use your USB port as an RS232 port.  You can find a manual for the cable [[Media:usb-rs232-ftdichip.pdf|here]].  You connect the cable's Tx (transmit data) pin with your PIC's Rx (receive data, pin 26), the cable's Rx pin with your PIC's Tx (pin 25), and the cable's ground with the PIC's ground, and you're all set.  The circuitry inside the cable takes care of the USB to RS232 as well as voltage-level shifting.  This cable also provides a 5V output which you can use to power an xbee wireless modem, for example (the xbee needs a 3.3V regulator).
 The only drawback of this cable is that it costs a bit more than the cheaper, less convenient option below.  Also, please check to make sure that the USB-RS232 driver software does not interfere with your PIC's ICD driver software.

@@ Line 28: / Line 28: @@
 The TTL-232R cable has six wires, color coded and in this sequence on the SIP connector:
-    BLACK   GROUND  Connect to PIC ground
+    BLACK   GROUND  Connect to PIC ground.
-    BROWN   CTS#    Unused. "Clear to send"
+    BROWN   CTS#    Unused. "Clear to send" (flow control).
     RED     Vcc     +5V from PC.  !!  DO NOT CONNECT TO PIC +5  !!
-    ORANGE  Tx      "PC Transmit." Data from PC, to PIC Rx (pin 26)
+    ORANGE  Tx      "PC Transmit." Data from PC, to PIC Rx (pin 26).
-    YELLOW  Rx      "PC Receive."  Data from PIC Tx (pin 25), to PC
+    YELLOW  Rx      "PC Receive."  Data from PIC Tx (pin 25), to PC.
-    GREEN   RTS#    Unused.
+    GREEN   RTS#    Unused. "Request to send" (flow control).
 Note that the TTL-232R cable gives you access to the PC's +5 supply (Red wire), which is limited in current (probably to 500mA) by the USB port which is designed to protect from short circuits.   If you wish, you can probably power your PIC from the PC, using USB as a power source.   If you do that, get rid of any other +5 source.  <b>Don't</b> connect two +5 sources at once.  In contrast, be sure that you <b>do</b> connect the PIC's ground to the PC's ground (Black wire).

@@ Line 41: / Line 41: @@
 <br clear=all>
-== Alternate USB to RS232 Cable ==
+== The HL-340 USB to RS232 Cable ==
 [[Image:usb-serial-adapter2.jpg|right]]
-Cables such as the one pictured at right can be bought for as low as a few dollars, on ebay for example.  This cable serves the same purpose as the cable above, but it is a bit less convenient for a few reasons: (1) the RS232 voltages are high level (+12V and -7V) and must be level-shifted before interfacing with the PIC; (2) the cable breaks out into a DB-9 connector, so you have to have (or solder) your own connector; and (3) it doesn't provide +5V to power external devices, as the cable above does.  Nonetheless, it works just fine; just make sure you follow the instructions below.
+Cables such as the HL-340 pictured at right can be bought for as low as a few dollars, on ebay for example.  This cable serves the same purpose as the cable above, but it is a bit less convenient for a few reasons: (1) the RS232 voltages are high level (+12V and -7V) and must be level-shifted before interfacing with the PIC; (2) the cable breaks out into a DB-9 connector, so you have to have (or solder) your own connector; and (3) it doesn't provide +5V to power external devices, as the cable above does.  Nonetheless, it works just fine; just install the driver at http://129.105.69.13/pic/usb_drivers/HL-340_USB_serial_drivers_WinXP/ and make sure you follow the instructions below.
 [[Image:db9.jpg|right]]

@@ Line 45: / Line 45: @@
 [[Image:usb-serial-adapter2.jpg|right]]
-Cables such as the one pictured at right can be bought for as low as a few dollars on ebay, for example.  This cable serves the same purpose as the cable above, but it is a bit less convenient for a few reasons: (1) the RS232 voltages are high level (+12V and -7V) and must be level-shifted before interfacing with the PIC; (2) the cable breaks out into a DB-9 connector, so you have to have (or solder) your own connector; and (3) it doesn't provide +5V to power external devices, as the cable above does.  Nonetheless, it works just fine; just make sure you follow the instructions below.
+Cables such as the one pictured at right can be bought for as low as a few dollars, on ebay for example.  This cable serves the same purpose as the cable above, but it is a bit less convenient for a few reasons: (1) the RS232 voltages are high level (+12V and -7V) and must be level-shifted before interfacing with the PIC; (2) the cable breaks out into a DB-9 connector, so you have to have (or solder) your own connector; and (3) it doesn't provide +5V to power external devices, as the cable above does.  Nonetheless, it works just fine; just make sure you follow the instructions below.
 [[Image:db9.jpg|right]]

← Older revision		Revision as of 02:54, 21 February 2008
Line 35:		Line 35:
	GREEN RTS# Unused.		GREEN RTS# Unused.

	Note that the TTL-232R cable gives you access to the PC's +5 supply (Red wire), which is limited in current (probably to 500mA) by the USB port which is designed to protect from short circuits. If you wish, you can probably power your PIC from the PC, using USB as a power source. If you do that, get rid of any other +5 source. Don't connect two +5 sources at once. In contrast, be sure that you <b>do</b> connect the PC's ground to the ~~PIC~~'s ground (Black wire).		Note that the TTL-232R cable gives you access to the PC's +5 supply (Red wire), which is limited in current (probably to 500mA) by the USB port which is designed to protect from short circuits. If you wish, you can probably power your PIC from the PC, using USB as a power source. If you do that, get rid of any other +5 source. Don't connect two +5 sources at once. In contrast, be sure that you <b>do</b> connect the PIC's ground to the PC's ground (Black wire).

@@ Line 30: / Line 30: @@
     BLACK   GROUND  Connect to PIC ground
     BROWN   CTS#    Unused. "Clear to send"
-    RED     Vcc     +5V from PC.  DO NOT CONNECT TO PIC +5  !!
+    RED     Vcc     +5V from PC.  !!  DO NOT CONNECT TO PIC +5  !!
-    ORANGE  Tx      Data from PC, to PIC Rx (pin 26)  "Transmit"
+    ORANGE  Tx      "Transmit." Data from PC, to PIC Rx (pin 26)
-    YELLOW  Rx      Data from PIC Tx pin 25, to PC  "Receive"
+    YELLOW  Rx      "Receive."  Data from PIC Tx (pin 25), to PC
     GREEN   RTS#    Unused.

← Older revision		Revision as of 02:50, 21 February 2008
Line 34:		Line 34:
	6 GREEN RTS# Unused.		6 GREEN RTS# Unused.

	Note that the TTL-232R cable gives you access to the PC's +5 supply, which is limited in current (probably to 500mA) by the USB port which is ~~supposed~~ to protect from short circuits. ~~You~~ ~~could~~, if you ~~want,~~ power your PIC from the PC, using ~~this~~ power source. If you do that, get rid of any other +5 source. Don't connect two +5 sources at once.		Note that the TTL-232R cable gives you access to the PC's +5 supply (Red wire), which is limited in current (probably to 500mA) by the USB port which is designed to protect from short circuits. If you wish, you can probably power your PIC from the PC, using USB as a power source. If you do that, get rid of any other +5 source. Don't connect two +5 sources at once. In contrast, be sure that you <b>do</b> connect the PC's ground to the PIC's ground (Black wire).