27 GRAPHICS ENGINE (GE)
S1C33L26 TECHNICAL MANUAL
Seiko Epson Corporation
27-53
D3
GE_STOP: GE Stop Control Bit
Forcibly terminates command execution.
1 (R/W): Stop
0 (R/W): – (default)
When 1 is written to GE_STOP, the GE stops executing after the current command being executed has
finished. GE_STOP is automatically reset to 0 after the command execution has finished.
D2
GE_RUN: GE Run Control Bit
Starts command execution.
1 (R/W): Run
0 (R/W): – (default)
When 1 is written to GE_RUN, the GE starts executing the command list beginning with the command
start address set in the GE_CMD_ADDR register. GE_RUN is automatically reset to 0 when the GE
starts fetching the 1st command.
D1
GE_HRST: GE Hot Reset Control Bit
Hot resets the GE.
1 (R/W): Reset
0 (R/W): Normal mode (default)
Hot reset initializes the GE with the command and work area address information maintained. The bus
is relinquished. Perform hot reset if a command execution is terminated due to an unexpected operation.
To perform hot reset, write 1 to GE_HRST. GE_HRST retains 1 and it returns to 0 upon completion of
the initialization.
The following information must be reset after a hot reset.
• Font (font configuration command)
• Clipping area (GE_CLIP_ST and GE_CLIP_END registers)
D0
GE_CRST: GE Cold Reset Control Bit
Cold resets the GE.
1 (R/W): Cold reset (default)
0 (R/W): Normal mode
Cold reset initializes the GE completely.
To perform cold reset, write 1 to GE_CRST. The reset state must be canceled by writing 0 to GE_
CRST. If the initialization has not finished yet at this time, GE_CRST retains 1 and it returns to 0 upon
completion of the initialization. After a cold reset, all the information must be reset.
Note that the GE_CRST cannot be set to 1 if DRAW_STS is 1 (while the GE is writing data to the work
area).
GE Interrupt Enable Register (GE_IE)
Register name Address
Bit
Name
Function
Setting
Init. R/W
Remarks
GE Interrupt
Enable Register
(GE_IE)
0x302444
(32 bits)
D31–17 –
reserved
–
–
–
0 when being read.
D16
GE_END_IE GE end-of-execution interrupt
enable
1 Enable
0 Disable
0
R/W
D15-9 –
reserved
–
–
–
0 when being read.
D8
GE_ERR_
IE0
Drawing error interrupt enable
1 Enable
0 Disable
0
R/W
D7–1 –
reserved
–
–
–
0 when being read.
D0
GE_ERR_
IE1
Calculation error interrupt enable
1 Enable
0 Disable
0
R/W
D[31:17] Reserved
D16
GE_END_IE: GE End-of-Execution Interrupt Enable Bit
Enables or disables interrupts caused by termination of command execution.
1 (R/W): Interrupt enabled
0 (R/W): Interrupt disabled (default)