Usage - Siemens ERTEC 200P-2 Manual

2.3.4.1.4 Usage

Usage of the GDMA controller is described below:
After reset, the DMA channels must be initialized. This is carried out in such a
way that jobs are defined in the Job Control registers and the transfer list is
written to DMA RAM
2.3.4.1.4.1 First step
First, "GDMA Registers Base Address" (GDMA_REG_ADR), "DMA Transfer
List Base Address" (GDMA_LIST_ADDR) and "Total Number of Transfers in
Transfer List" (LIST_SIZE) must be defined and the bit "Global Enable"
(DMA_EN) must be reset in the GDMA Control registers.
In the Job Control register, following fields must be defined:
First Transfer Number of the job (TRANSFER_PTR)
Job Priority (JOB_PRIO)
HW Job Start Selector (HW_SELECT)
Job Reset (JOB_RESET) must remain disabled (set to "0" after reset) if
running of the job is required.
Interrupt Request Generation Enable (INTR_EN)
Hardware Triggered Flow Enable (HW_FLOW_EN)
HW Job start enable (HW_JOB_START_EN) In the first step this bit must
remain disabled (set to "0" after reset). The job can be started by HW after
the second step is finished (transfer list must be defined).
Enable Job (JOB_EN) must be set to '1' (set to "0" after reset) if running of
the job is required.
Start Job by SW (SW_JOB_START) In the first step this bit must remain
disabled (set to "0" after reset). The job can be started by SW after the
second step is finished (transfer list must be defined).
2.3.4.1.4.2 Second step
Second step is to set up the transfer records in the transfer list. The transfer
record defines all parameters of a single DMA transfer and consists of four 32-
bit words:
Source Address
Destination Address
Transfer Control
Transfer Count
Copyright © Siemens AG 2016. All rights reserved
Technical data subject to change
.
consists of three 2-bit fields: Source Address Mode,
Destination Address Mode and Burst Mode, as described
above
114 ERTEC 200P-2 Manual
Version 1.0