83Plus:Ports:8F - Revision history

Dr. D'nar: Confirmed that port 8F is DEVCTL

2014-10-30T02:32:02Z

Confirmed that port 8F is DEVCTL

Dr. D'nar: Making some guesses based on the HDRC source

2013-08-14T21:18:40Z

Making some guesses based on the HDRC source

Thepenguin77 at 04:23, 28 October 2011

2011-10-28T04:23:07Z

Thepenguin77 at 04:07, 4 June 2011

2011-06-04T04:07:29Z

Thepenguin77: Created page with '8F - VBus Control VBus Control {{84P-Only Port|0F}} == Synopsis == '''Port Number:''' 8F '''Function:''' V…'

2011-06-04T03:38:37Z

Created page with '8F - VBus Control VBus Control {{84P-Only Port|0F}} == Synopsis == '''Port Number:''' 8F '''Function:''' V…'

New page

[[Category:83Plus:Ports:By Address|8F - VBus Control]] [[Category:83Plus:Ports:By Name|VBus Control]]
{{84P-Only Port|0F}}
== Synopsis ==
'''Port Number:''' 8F

'''Function:''' VBus Control

Using this port, you can control the VBus line and see its status.

=== Read Values ===
* Bit 0: Set if VBus is high. (Cutoff between 1.5 V and 3 V)
* Bit 1: Unknown. Peripheral routines like this bit.
* Bit 2: Set if calculator is host.
* Bit 3: Reset if VBus is externally powered.
* Bit 4: Set if VBus is externally powered.
* Bit 5: Always 0
* Bit 6: Set if calculator is successfully hosting a device. It gets set when the device turns on.
* Bit 7: Reset if A-Type cable is currently inserted.

=== Write Values ===
* Bit 0: Set to power VBus. This will only stick if the USB controller ports are set up correctly. Most notably [[83Plus:Ports:4C|port 4C]] and [[83Plus:Ports:54|port 54]].
* Bit 2: Unknown. Peripheral routines sometimes set this.
* Bits 3-7: No effect

== Comments ==
If VBus is internally powered and you short circuit it, it will power down. Bit 6 is most likely set if current is flowing through VBus and it is internally powered. But I'm having trouble testing that because every time I try, it powers off on me.

@@ Line 12: / Line 12: @@
 === Read Values ===
 * Bit 0:
 ** Set if VBus is high. (Cutoff between 1.5 V and 3 V)
 * Bit 1:
-** Unknown. Peripheral routines like this bit.
+** Named MGC_M_DEVCTL_HR in the HDRC
-** Possibly named MGC_M_DEVCTL_HR in the HDRC
+** Peripheral routines like this bit.
 * Bit 2:
 ** Set if calculator is host.
 * Bit 3:
 ** Reset if VBus is externally powered.
 * Bit 4:
 ** Set if VBus is externally powered.
 * Bit 5:
 ** Always 0
-** Possibly named MGC_M_DEVCTL_LSDEV in the HDRC
+** Named MGC_M_DEVCTL_LSDEV in the HDRC
 ** Possibly actually indicates whether the bus is in low-speed or full-speed
 * Bit 6:
 ** Set if calculator is successfully hosting a device. It gets set when the device turns on.
-** Possibly named MGC_M_DEVCTL_FSDEV in the HDRC
+** Named MGC_M_DEVCTL_FSDEV in the HDRC
 ** Possibly actually indicates whether the bus is in low-speed or full-speed
 * Bit 7:
-** Reset if A-Type cable is currently inserted.
+** Named M_DEVCTL_BDEVICE in the HDRC
-** Possibly named M_DEVCTL_BDEVICE in the HDRC
+** Set if we are B-device (i.e. peripheral). This can change if you're implementing USB OTG.
 === Write Values ===
@@ Line 44: / Line 44: @@
 == Comments ==
 If VBus is internally powered and you short circuit it, it will power down.
-−
-Bit 6 is pretty strange, it's not as simple as VBus high, or even VBus supplying power. I lit an LED drawing 30 mA off of VBus and port 6 stayed off. But .5 sec after I plug in a USB device, it sets itself.

← Older revision		Revision as of 04:07, 4 June 2011
Line 24:		Line 24:

	== Comments ==		== Comments ==
−	If VBus is internally powered and you short circuit it, it will power down. Bit 6 is ~~most likely set if current is flowing through~~ VBus and ~~it is internally powered~~. But I~~'m having trouble testing that because every time I try~~, it ~~powers off on me~~.	+	If VBus is internally powered and you short circuit it, it will power down.
		+
		+	Bit 6 is pretty strange, it's not as simple as VBus high, or even VBus supplying power. I lit an LED drawing 30 mA off of VBus and port 6 stayed off. But .5 sec after I plug in a USB device, it sets itself.

@@ Line 3: / Line 3: @@
 == Synopsis ==
 '''Port Number:''' 8F
 '''Function:''' VBus Control
@@ Line 9: / Line 11: @@
 === Read Values ===
-* Bit 0: Set if VBus is high. (Cutoff between 1.5 V and 3 V)
+* Bit 0:
-* Bit 1: Unknown. Peripheral routines like this bit.
+** Set if VBus is high. (Cutoff between 1.5 V and 3 V)
-* Bit 2: Set if calculator is host.
+** Possibly named MGC_M_DEVCTL_SESSION in the HDRC
-* Bit 3: Reset if VBus is externally powered.
+* Bit 1:
-* Bit 4: Set if VBus is externally powered.
+** Unknown. Peripheral routines like this bit.
-* Bit 5: Always 0
+** Possibly named MGC_M_DEVCTL_HR in the HDRC
-* Bit 6: Set if calculator is successfully hosting a device. It gets set when the device turns on.
+* Bit 2:
-* Bit 7: Reset if A-Type cable is currently inserted.
+** Set if calculator is host.
 === Write Values ===

@@ Line 1: / Line 1: @@
 [[Category:83Plus:Ports:By Address|8F - VBus Control]] [[Category:83Plus:Ports:By Name|VBus Control]]
-{{84P-Only Port|0F}}
+{{84P-Only Port|07}}
 == Synopsis ==
 '''Port Number:''' 8F