Motorola MVME1X7P User Manual
LCSR Programming Model
http://www.motorola.com/computer/literature
2-51
2
I2WP
When this bit is high, write posting is enabled to the local
bus F page. When this bit is low, write posting is disabled
to the local bus F page.
bus F page. When this bit is low, write posting is disabled
to the local bus F page.
I2EN
When this bit is high, the F page ($F0000000 through
$FF7FFFFF) map decoder is enabled. The F0 page is
defined as A24/D16 on the VMEbus while the F1-FE
pages are defined as A32/D16. When this bit is low, the F
page is disabled.
$FF7FFFFF) map decoder is enabled. The F0 page is
defined as A24/D16 on the VMEbus while the F1-FE
pages are defined as A32/D16. When this bit is low, the F
page is disabled.
ROM Control Register
This function is not used on the MVME1x7P.
Programming the VMEchip2 DMA Controller
This section includes programming information on the DMA controller,
VMEbus interrupter, MPU status register, and local-bus-to-VMEbus
requester register.
VMEbus interrupter, MPU status register, and local-bus-to-VMEbus
requester register.
The VMEchip2 features a local-bus -to-VMEbus DMA controller
(DMAC). The DMAC has two modes of operation: command chaining,
and direct. In direct mode, the local bus address, the VMEbus address, the
byte count, and the control register of the DMAC are programmed and the
DMAC is enabled. The DMAC transfers data, as programmed, until the
byte count is zero or an error is detected. When the DMAC stops, the status
bits in the DMAC status register are set and an interrupt is sent to the local
bus interrupter. If the DMAC interrupt is enabled in the local bus
interrupter, the local bus is interrupted. The time on and time off timers
should be programmed to control the VMEbus bandwidth used by the
DMAC.
(DMAC). The DMAC has two modes of operation: command chaining,
and direct. In direct mode, the local bus address, the VMEbus address, the
byte count, and the control register of the DMAC are programmed and the
DMAC is enabled. The DMAC transfers data, as programmed, until the
byte count is zero or an error is detected. When the DMAC stops, the status
bits in the DMAC status register are set and an interrupt is sent to the local
bus interrupter. If the DMAC interrupt is enabled in the local bus
interrupter, the local bus is interrupted. The time on and time off timers
should be programmed to control the VMEbus bandwidth used by the
DMAC.
ADR/SIZ
$FFF4002C
BIT
7
6
5
4
3
2
1
0
NAME
SIZE
BSSPD
ASPD
OPER
R/W
R/W
R/W
RESET
0 PS
0 PS
0 PS