Difference between revisions of "83Plus:Ports:8F"
From WikiTI
(Making some guesses based on the HDRC source) |
(Confirmed that port 8F is DEVCTL) |
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=== Read Values === | === Read Values === | ||
* Bit 0: | * Bit 0: | ||
+ | ** Named MGC_M_DEVCTL_SESSION in the HDRC | ||
** Set if VBus is high. (Cutoff between 1.5 V and 3 V) | ** Set if VBus is high. (Cutoff between 1.5 V and 3 V) | ||
− | |||
* Bit 1: | * Bit 1: | ||
− | ** | + | ** Named MGC_M_DEVCTL_HR in the HDRC |
− | + | ** Peripheral routines like this bit. | |
* Bit 2: | * Bit 2: | ||
+ | ** Named MGC_M_DEVCTL_HM in the HDRC | ||
** Set if calculator is host. | ** Set if calculator is host. | ||
− | |||
* Bit 3: | * Bit 3: | ||
+ | ** Named MGC_M_DEVCTL_VBUS in the HDRC | ||
** Reset if VBus is externally powered. | ** Reset if VBus is externally powered. | ||
− | |||
* Bit 4: | * Bit 4: | ||
+ | ** Named MGC_M_DEVCTL_VBUS in the HDRC | ||
** Set if VBus is externally powered. | ** Set if VBus is externally powered. | ||
− | |||
* Bit 5: | * Bit 5: | ||
** Always 0 | ** Always 0 | ||
− | ** | + | ** Named MGC_M_DEVCTL_LSDEV in the HDRC |
** Possibly actually indicates whether the bus is in low-speed or full-speed | ** Possibly actually indicates whether the bus is in low-speed or full-speed | ||
* Bit 6: | * Bit 6: | ||
** Set if calculator is successfully hosting a device. It gets set when the device turns on. | ** Set if calculator is successfully hosting a device. It gets set when the device turns on. | ||
− | ** | + | ** Named MGC_M_DEVCTL_FSDEV in the HDRC |
** Possibly actually indicates whether the bus is in low-speed or full-speed | ** Possibly actually indicates whether the bus is in low-speed or full-speed | ||
* Bit 7: | * Bit 7: | ||
− | ** | + | ** 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 === | === Write Values === | ||
Line 44: | Line 44: | ||
== Comments == | == Comments == | ||
− | If VBus is internally powered and you short circuit it, it will power down | + | If VBus is internally powered and you short circuit it, it will power down. |
− | + | ||
− | + |
Latest revision as of 19:32, 29 October 2014
This port only exists on the the TI-84 Plus and the TI-84 Plus Silver Edition. On the standard TI-83 Plus, it acts as a shadow of port 07. On the TI-83 Plus Silver Edition, this port has no effect. |
Synopsis
Port Number: 8F
Equivalent HDRC port: Possibly MGC_O_HDRC_DEVCTL (0x60)
Function: VBus Control
Using this port, you can control the VBus line and see its status.
Read Values
- Bit 0:
- Named MGC_M_DEVCTL_SESSION in the HDRC
- Set if VBus is high. (Cutoff between 1.5 V and 3 V)
- Bit 1:
- Named MGC_M_DEVCTL_HR in the HDRC
- Peripheral routines like this bit.
- Bit 2:
- Named MGC_M_DEVCTL_HM in the HDRC
- Set if calculator is host.
- Bit 3:
- Named MGC_M_DEVCTL_VBUS in the HDRC
- Reset if VBus is externally powered.
- Bit 4:
- Named MGC_M_DEVCTL_VBUS in the HDRC
- Set if VBus is externally powered.
- Bit 5:
- Always 0
- 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.
- Named MGC_M_DEVCTL_FSDEV in the HDRC
- Possibly actually indicates whether the bus is in low-speed or full-speed
- Bit 7:
- 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
- Bit 0: Set to power VBus. This will only stick if the USB controller ports are set up correctly. Most notably port 4C and 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.